Question: what are the transmission routes of coronavirus?

Title: [Transmission routes of 2019-novel coronavirus (2019-nCoV)] Content: Since the outbreak of COVID-19 in Wuhan, China, at the end of 2019, it has demonstrated China's ability to identify unknown pathogens. At present, reports showed that the main transmission routes are respiratory droplets and indirect contact, other vertical transmission routes have yet to be confirmed. This review discusses the possible transmission routes of 2019-novel coronavirus (2019-nCoV), based on currently research, the main transmission routes are respiratory droplets and indirect contact, fecal-oral might bepossible, while aerosol, tear (conjunctival) and mother-to-fetus still have yet to be confirmed, providing a reference basis for 2019-nCoV prevention and control and public protection.

Title: [Transmission routes of 2019-novel coronavirus (2019-nCoV)]. Content: Since the outbreak of COVID-19 in Wuhan, China, at the end of 2019, it has demonstrated China's ability to identify unknown pathogens. At present, reports showed that the main transmission routes are respiratory droplets and indirect contact, other vertical transmission routes have yet to be confirmed. This review discusses the possible transmission routes of 2019-novel coronavirus (2019-nCoV), based on currently research, the main transmission routes are respiratory droplets and indirect contact, fecal-oral might bepossible, while aerosol, tear (conjunctival) and mother-to-fetus still have yet to be confirmed, providing a reference basis for 2019-nCoV prevention and control and public protection.

Title: Indirect Virus Transmission in Cluster of COVID-19 Cases, Wenzhou, China, 2020 Content: To determine possible modes of virus transmission, we investigated a cluster of coronavirus disease cases associated with a shopping mall in Wenzhou, China. Data indicated that indirect transmission of the causative virus occurred, perhaps resulting from virus contamination of common objects, virus aerosolization in a confined space, or spread from asymptomatic infected persons.

Title: Ventilation in the Dental Clinic: An Effective Measure to Control Droplets and Aerosols during the Coronavirus Pandemic and Beyond. Content: Clinical and epidemiological studies suggest that human-to-human transmission of coronavirus disease 2019 (COVID-19) most frequently occurs through virus-laden respiratory droplets discharged from infected individuals while coughing and sneezing. Aerosols can act as another potential transmission route. The World Health Organisation (WHO) has advised medical personnel to consider taking 'airborne precautions'. It is important to protect dentists and patients and reduce the amount of spatter produced during dental procedures. In order to prevent airborne transmission, dental offices should be sufficiently ventilated, with great emphasis placed upon removing bioaerosols.

Title: Airborne route and bad use of ventilation systems as non-negligible factors in SARS-CoV-2 transmission Content: Summary The world is facing a pandemic of unseen proportions caused by a corona virus named SARS-CoV-2 with unprecedent worldwide measures being taken to tackle its contagion. Person-to-person transmission is accepted but WHO only considers aerosol transmission when procedures or support treatments that produce aerosol are performed. However, transmission mechanisms are not fully understood and there is evidence for an airborne route to be considered as the virus remains viable in aerosols for at least 3h and that mask usage was the best intervention to prevent infection. Heating, Ventilating and Air Conditioning Systems (HVAC) are used as a primary infection disease control measure. However, they may contribute to the transmission/spreading of airborne diseases as proposed in the past for SARS. The authors believe that airborne transmission is possible and that HVAC systems when not adequately used may contribute to the transmission of the virus, as suggested by descriptions of from Japan, Germany, and the Diamond Princess Cruise Ship. Previous SARS outbreaks reported at Amoy Gardens, Emergency Rooms and Hotels, for example, also suggested airborne transmission. Further studies are warranted to confirm our hypotheses but the assumption of such way of transmission would cause a major shift in measures recommended to prevent infection such as the disseminated use of masks and structural changes to hospital and other facilities HVAC systems.

Title: Transference of COVID-19 patient in hospitals – A crucial phase Content: • COVID-19 virus is primarily transmitted between humans through respiratory droplets and contact routes. • Transportation of COVID-19 patient carries very high transmission risk to personals involved. • Worldwide, clinicians are using many measures that can be executed easily to prevent aerosol exposure.

Title: Effect of Nonpharmaceutical Interventions on Transmission of Severe Acute Respiratory Syndrome Coronavirus 2, South Korea, 2020 Content: We analyzed transmission of coronavirus disease outside of the Daegu-Gyeongsangbuk provincial region in South Korea. We estimated that nonpharmaceutical measures reduced transmissibility by a maximum of 34% without resorting to a strict lockdown strategy. To optimize epidemic control, continuous efforts to monitor the transmissibility are needed.

Title: Effect of Nonpharmaceutical Interventions on Transmission of Severe Acute Respiratory Syndrome Coronavirus 2, South Korea, 2020. Content: We analyzed transmission of coronavirus disease outside of the Daegu-Gyeongsangbuk provincial region in South Korea. We estimated that nonpharmaceutical measures reduced transmissibility by a maximum of 34% without resorting to a strict lockdown strategy. To optimize epidemic control, continuous efforts to monitor the transmissibility are needed.

Title: Cross host transmission in the emergence of MERS coronavirus Content: Coronaviruses (CoVs) able to infect humans emerge through cross-host transmission from animals. There is substantial evidence that the recent Middle East respiratory syndrome (MERS)-CoV outbreak is fueled by zoonotic transmission from dromedary camels. This is largely based on the fact that closely related viruses have been isolated from this but not any other animal species. Given the widespread geographical distribution of dromedaries found seropositive for MERS-CoV, continued transmission may likely occur in the future. Therefore, a further understanding of the cross host transmission of MERS-CoV is needed to limit the risks this virus poses to man.

Title: Animal-to-Human Viral Transitions: Is SARS-CoV-2 an Evolutionary Successful One? Content: Transmission of viruses from one species to another is not unusual in nature. Despite this, evolutionarily successful transmissions are rare. Such events can cause pandemics and are followed by host–virus coevolution procedures that can increase the fitness potential of viruses. In this perspective article, I recognize eight main types of trans-species viral transmission. I consider two of them as evolutionarily successful, explaining why coronavirus SARS-CoV-2 could be one of them.

Title: Airborne route and bad use of ventilation systems as non-negligible factors in SARS-CoV-2 transmission Content: The world is facing a pandemic of unseen proportions caused by a corona virus named SARS-CoV-2 with unprecedent worldwide measures being taken to tackle its contagion. Person-to-person transmission is accepted but WHO only considers aerosol transmission when procedures or support treatments that produce aerosol are performed. Transmission mechanisms are not fully understood and there is evidence for an airborne route to be considered, as the virus remains viable in aerosols for at least 3 h and that mask usage was the best intervention to prevent infection. Heating, Ventilation and Air Conditioning Systems (HVAC) are used as a primary infection disease control measure. However, if not correctly used, they may contribute to the transmission/spreading of airborne diseases as proposed in the past for SARS. The authors believe that airborne transmission is possible and that HVAC systems when not adequately used may contribute to the transmission of the virus, as suggested by descriptions from Japan, Germany, and the Diamond Princess Cruise Ship. Previous SARS outbreaks reported at Amoy Gardens, Emergency Rooms and Hotels, also suggested an airborne transmission. Further studies are warranted to confirm our hypotheses but the assumption of such way of transmission would cause a major shift in measures recommended to prevent infection such as the disseminated use of masks and structural changes to hospital and other facilities with HVAC systems.

Title: SARS‐CoV‐2 possible contamination of genital area: implications for sexual and vertical transmission routes Content: The severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) is responsible for a pandemic that is causing thousands of deaths worldwide. The virus can be transmitted from person to person, directly or indirectly, via the respiratory, oro‐fecal and probably sexual routes.(1) The eventual vertical transmission route is still poorly explored. However, mother‐to‐child SARS‐CoV‐2 transmission through the placenta probably does not occur, or likely occurs very rarely.(2) All the studies conducted on COVID‐19 pregnant women involved patients undergoing cesarean section, but the indications for such delivery modality were not clearly stated.

Title: COVID 19 in neonates Content: Corona virus disease 2019 started in December 2019 as an outbreak of unexplained pneumonias in Wuhan, a city in Hubei province of China. This illness emerged as an epidemic in China and later spread to almost all countries over the globe except Antarctica. This is caused by a beta Corona virus, which is genetically similar to SARS virus. The predominant mode of transmission is via droplet spread, when the infected person coughs, sneezes or talks the virus is released in the respiratory secretions. As there are only a few cases of COVID 19 in neonates, there is no convincing evidence to support the possibility of vertical transmission. Clinical presentation in neonates is nonspecific, commonly observed are temperature instability, respiratory distress, poor feeding, lethargy, vomiting and diarrhea. Laboratory examinations may be nonspecific. Definitive test for 2019-nCoV is the detection of viral nucleic acid by real-time fluorescence polymerase chain reaction (RT-PCR). Suspected and confirmed COVID positive mothers should be delivered in separate delivery rooms and operation theaters. Since there is no approved treatment or drug for this disease, prevention of infection and breaking the chain of transmission plays a crucial role.

Title: COVID 19 in neonates. Content: Corona virus disease 2019 started in December 2019 as an outbreak of unexplained pneumonias in Wuhan, a city in Hubei province of China. This illness emerged as an epidemic in China and later spread to almost all countries over the globe except Antarctica. This is caused by a beta Corona virus, which is genetically similar to SARS virus. The predominant mode of transmission is via droplet spread, when the infected person coughs, sneezes or talks the virus is released in the respiratory secretions. As there are only a few cases of COVID 19 in neonates, there is no convincing evidence to support the possibility of vertical transmission. Clinical presentation in neonates is nonspecific, commonly observed are temperature instability, respiratory distress, poor feeding, lethargy, vomiting and diarrhea. Laboratory examinations may be nonspecific. Definitive test for 2019-nCoV is the detection of viral nucleic acid by real-time fluorescence polymerase chain reaction (RT-PCR). Suspected and confirmed COVID positive mothers should be delivered in separate delivery rooms and operation theaters. Since there is no approved treatment or drug for this disease, prevention of infection and breaking the chain of transmission plays a crucial role.

Title: History is repeating itself: Probable zoonotic spillover as the cause of the 2019 novel Coronavirus Epidemic Content: Pathogen transmission from a vertebrate animal to a human, also known as zoonotic spillover, represents a global public health burden, which while associated with multiple outbreaks, still remains a poorly understood phenomenon. Coronaviruses, like influenza viruses, circulate in nature in various animal species. Alpha-coronaviruses and beta-coronaviruses can infect mammals and gamma-coronaviruses and delta-coronaviruses tend to infect birds, but some of them can also be transmitted to mammals. Although still preliminary, current data suggest that bats are the most probable initial source of the current 2019 novel CoV (2019nCoV) outbreak, that begun on December 2019 in Wuhan, China, apparently spreading from a "wet market" to multiple cities and provinces in China. This epidemic of 2019nCoV, already reaching more than 6,000 cases to-day (end of January 2020) (>90% in China), will not be the last one linked to zoonotic spillover events.

Title: History is repeating itself, a probable zoonotic spillover as a cause of an epidemic: the case of 2019 novel Coronavirus. Content: Pathogen transmission from a vertebrate animal to a human, also known as zoonotic spillover, represents a global public health burden, which while associated with multiple outbreaks, still remains a poorly understood phenomenon. Coronaviruses, like influenza viruses, circulate in nature in various animal species. Alpha-coronaviruses and beta-coronaviruses can infect mammals and gamma-coronaviruses and delta-coronaviruses tend to infect birds, but some of them can also be transmitted to mammals. Although still preliminary, current data suggest that bats are the most probable initial source of the current 2019 novel CoV (2019nCoV) outbreak, that begun on December 2019 in Wuhan, China, apparently spreading from a "wet market" to multiple cities and provinces in China. This epidemic of 2019nCoV, already reaching more than 6,000 cases to-day (end of January 2020) (>90% in China), will not be the last one linked to zoonotic spillover events.

Title: Animal-to-Human Viral Transitions: Is SARS-CoV-2 an Evolutionarily Successful One? Content: Transmission of viruses from one species to another is not unusual in nature. Despite this, evolutionarily successful transmissions are rare. Such events can cause pandemics and are followed by host-virus coevolution procedures that can increase the fitness potential of viruses. In this perspective article, I recognize eight main types of trans-species viral transmission. I consider two of them as evolutionarily successful, explaining why coronavirus SARS-CoV-2 could be one of them.

Title: Coronavirus: An emergency for healthcare professionals Content: Coronavirus infection is a transmissible disease. It was first described in China in December, 2019. It has been said to have a person-to-person transmission after prolonged and unprotected exposure. Patients with a potential SARS-CoV-2 exposure present with symptoms of low-grade pyrexia, dry cough, or shortness of breath. People with these symptoms should contact health-care providers before seeking medical intervention so that appropriate preventive actions may be implemented. Health-care facilities should rapidly isolate suspected individuals and notify local health departments for support involved in performing laboratory tests and efforts in containment. The present article describes the nature of virus, method of detection, and its mode of transmission.

Title: Transmission routes of 2019-nCoV and controls in dental practice Content: A novel β-coronavirus (2019-nCoV) caused severe and even fetal pneumonia explored in a seafood market of Wuhan city, Hubei province, China, and rapidly spread to other provinces of China and other countries. The 2019-nCoV was different from SARS-CoV, but shared the same host receptor the human angiotensin-converting enzyme 2 (ACE2). The natural host of 2019-nCoV may be the bat Rhinolophus affinis as 2019-nCoV showed 96.2% of whole-genome identity to BatCoV RaTG13. The person-to-person transmission routes of 2019-nCoV included direct transmission, such as cough, sneeze, droplet inhalation transmission, and contact transmission, such as the contact with oral, nasal, and eye mucous membranes. 2019-nCoV can also be transmitted through the saliva, and the fetal–oral routes may also be a potential person-to-person transmission route. The participants in dental practice expose to tremendous risk of 2019-nCoV infection due to the face-to-face communication and the exposure to saliva, blood, and other body fluids, and the handling of sharp instruments. Dental professionals play great roles in preventing the transmission of 2019-nCoV. Here we recommend the infection control measures during dental practice to block the person-to-person transmission routes in dental clinics and hospitals.

Title: [Coronavirus, emerging viruses]. Content: Coronavirus is a large family of viruses that infect mammals and birds. Coronaviruses are known to cross barrier species and infect new ones. In the past twenty years, we witnessed the emergence of three different coronaviruses, the latest one being the SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) responsible for the COVID-19 (covid disease 19) pandemic. Coronaviruses are enveloped virus with a long positive sense RNA genome. Like all viruses, they hijack the cellular machinery to replicate and produce new virions. There is no approved vaccine or specific antiviral molecule against coronaviruses but with the urgency to treat COVID-19, several candidate therapies are currently investigated.

Title: Potential fecal transmission of SARS-CoV-2: Current evidence and implications for public health Content: Coronavirus disease 2019 (COVID-19) emerged in Hubei Province, China in December 2019 and has since become a global pandemic, with hundreds of thousands of cases and over 165 countries affected. Primary routes of transmission of the causative virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), are through respiratory droplets and close person-to-person contact. While information about other potential modes of transmission are relatively sparse, evidence supporting the possibility of a fecally mediated mode of transmission has been accumulating. Here, current knowledge on the potential for fecal transmission is briefly reviewed and the possible implications are discussed from a public health perspective.

Title: Transmission of SARS-CoV-2 via fecal-oral and aerosols-borne routes: Environmental dynamics and implications for wastewater management in underprivileged societies Content: The advent of novel human coronavirus (SARS-CoV-2) and its potential transmission via fecal-oral and aerosols-borne routes are upcoming challenges to understand the fate of the virus in the environment. In this short communication, we specifically looked at the possibilities of these transmission routes based on the available literature directly related to the SARS-CoV-2 as well as on the closer phylogenetic relatives such as SARS-CoV-1. The available data suggest that, in addition to human-to-human contact, the virus may spread via fecal-oral and aerosols-borne routes. Existing knowledge states that coronaviruses have low stability in the environment due to the natural action of oxidants that disrupt the viral envelope. Previous recommended dosage of chlorination has been found to be not sufficient to inactivate SARS-CoV-2 in places where viral load is high such as hospitals and airports. Although there is no current evidence showing that coronaviruses can be transmitted through contaminated drinking water, there is a growing concern on the impact of the current pandemic wave on underprivileged societies because of their poor wastewater treatment infrastructures, overpopulation, and outbreak management strategies. More research is encouraged to trace the actual fate of SARS-CoV-2 in the environment and to develop/revise the disinfection strategies accordingly.

Title: Transmission of SARS-CoV-2 via fecal-oral and aerosols–borne routes: Environmental dynamics and implications for wastewater management in underprivileged societies Content: Abstract The advent of novel human coronavirus (SARS-CoV-2) and its potential transmission via fecal-oral and aerosols-borne routes are upcoming challenges to understand the fate of the virus in the environment. In this short communication, we specifically looked at the possibilities of these transmission routes based on the available literature directly related to the SARS-CoV-2 as well as on the closer phylogenetic relatives such as SARS-CoV-1. The available data suggest that, in addition to human-to-human contact, the virus may spread via fecal-oral and aerosols-borne routes. Existing knowledge states that coronaviruses have low stability in the environment due to the natural action of oxidants that disrupt the viral envelope. Previous recommended dosage of chlorination has been found to be not sufficient to inactivate SARS-CoV-2 in places where viral load is high such as hospitals and airports. Although there is no current evidence showing that coronaviruses can be transmitted through contaminated drinking water, there is a growing concern on the impact of the current pandemic wave on underprivileged societies because of their poor wastewater treatment infrastructures, overpopulation, and outbreak management strategies. More research is encouraged to trace the actual fate of SARS-CoV-2 in the environment and to develop/revise the disinfection strategies accordingly.

Title: [Replication and transmission mechanisms of highly pathogenic human coronaviruses]. Content: The three known human highly pathogenic coronaviruses are severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus, (MERS-CoV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Human highly pathogenic coronaviruses are composed of non-structural proteins, structural proteins and accessory proteins. Viral particles recognize host receptors via spike glycoprotein (S protein), enter host cells by membrane fusion, replicate in host cells through large replication-transcription complexes, and promote proliferation by interfering with and suppressing the host's immune response. Human highly pathogenic coronaviruses are hosted by humans and vertebrates. Viral particles are transmitted through droplets, contact and aerosols or likely through digestive tract, urine, eyes and other routes. This review discusses the mechanisms of proliferation and transmission of highly pathogenic human coronaviruses based on the results of existing research, providing basis for future study on interrupting the transmission and pathogenicity of human highly pathogenic coronaviruses.

Title: A letter about the airborne transmission of sars-cov-2 based on the current evidence Content: World Health Organization has suggested that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is transmitted through person-to-person transmission and contact with contaminated surfaces. However, rapid spread of the coronavirus disease 2019 (COVID-19) suggests other routes such as airborne transmission may be involved. A few research studies have been conducted to evaluate the potential transmission of this virus through air. Although some studies have found no evidence of airborne transmission, other more recent work is proving the presence of SARS-CoV-2 even in public places. Also, the past experiences and knowledge about the mechanisms of similar viruses such as SARS-CoV support this hypothesis. It seems that the best decision at the moment is to follow a conservative approach, and accept the hypothesis that SARS-CoV-2 is able to be transmitted through air. By this, control measures could be employed to prevent further COVID-19 infection.

Title: Hand disinfection in the combat against Covid-19 Content: The World Health Organization (WHO) has declared a global health emergency over a new coronavirus. The new corona virus (SARS-CoV-2) has raised global attention with raising concerns of rapid spread from human-to-human. Like severe acute respiratory syndrome (SARS)-nCoV, 2019-nCoV can be passed directly from person to person by respiratory droplets, and may also be transmitted through contact and fomites.

Title: Transmission routes of 2019-nCoV and controls in dental practice Content: A novel ß-coronavirus (2019-nCoV) caused severe and even fetal pneumonia explored in a seafood market of Wuhan city, Hubei province, China, and rapidly spread to other provinces of China and other countries. The 2019-nCoV was different from SARS-CoV, but shared the same host receptor the human angiotensin-converting enzyme 2 (ACE2). The natural host of 2019-nCoV may be the bat Rhinolophus affinis as 2019-nCoV showed 96.2% of whole-genome identity to BatCoV RaTG13. The person-to-person transmission routes of 2019-nCoV included direct transmission, such as cough, sneeze, droplet inhalation transmission, and contact transmission, such as the contact with oral, nasal, and eye mucous membranes. 2019-nCoV can also be transmitted through the saliva, and the fetal-oral routes may also be a potential person-to-person transmission route. The participants in dental practice expose to tremendous risk of 2019-nCoV infection due to the face-to-face communication and the exposure to saliva, blood, and other body fluids, and the handling of sharp instruments. Dental professionals play great roles in preventing the transmission of 2019-nCoV. Here we recommend the infection control measures during dental practice to block the person-to-person transmission routes in dental clinics and hospitals.

Title: COVID-19 and animals: What do we know? Content: Coronaviruses, which were generally considered harmless to humans before 2003, have appeared again with a pandemic threatening the world since December 2019 after the epidemics of SARS and MERS. It is known that transmission from person to person is the most important way to spread. However, due to the widespread host diversity, a detailed examination of the role of animals in this pandemic is essential to effectively fight against the outbreak. Although coronavirus infections in pets are known to be predominantly related to the gastrointestinal tract, it has been observed that there are human-to-animal transmissions in this outbreak and some animals have similar symptoms to humans. Although animal-to-animal transmission has been shown to be possible, there is no evidence of animal-to-human transmission.

Title: Making waves: Coronavirus detection, presence and persistence in the water environment: State of the art and knowledge needs for public health Content: The main route of transmission of the human coronaviruses (HCoVs), and presumably also of the new pandemic SARS-CoV-2, is via droplets and close contacts, however their fecal elimination also suggests the possible spread via water. A scientific literature search was thus carried out to highlight the current state of the art and knowledge gaps regarding coronavirus in water. Since 1978 only 22 studies have met the inclusion criteria, and considered heterogeneous purposes, detection methods and types of water. In vitro experiments have addressed the recovery efficiency of analytical methods, survival in different types of water and the removal efficiency of water treatments. Field studies have monitored coronaviruses in surface waters, sewage, slurry, and biosolids. Overall, at the lab scale, HCoVs or surrogates can survive for several days at 4 °C, however their persistence is lower compared with non-enveloped viruses and is strongly influenced by temperature and organic or microbial pollution. HCoVs have rarely been detected in field investigations, however may be due to the low recovery efficiency of the analytical methods. The scarcity of information on HCoV in the environment suggests that research is needed to understand the fate of these viruses in the water cycle.

Title: Making Waves: Coronavirus detection, presence and persistence in the water environment: State of the art and knowledge needs for public health Content: The main route of transmission of the human coronaviruses (HCoVs), and presumably also of the new pandemic SARS-CoV-2, is via droplets and close contacts, however their fecal elimination also suggests the possible spread via water. A scientific literature search was thus carried out to highlight the current state of the art and knowledge gaps regarding coronavirus in water. Since 1978 only 22 studies have met the inclusion criteria, and considered heterogeneous purposes, detection methods and types of water. In vitro experiments have addressed the recovery efficiency of analytical methods, survival in different types of water and the removal efficiency of water treatments. Field studies have monitored coronaviruses in surface waters, sewage, slurry, and biosolids. Overall, at the lab scale, HCoVs or surrogates can survive for several days at 4 °C, however their persistence is lower compared with non-enveloped viruses and is strongly influenced by temperature and organic or microbial pollution. HCoVs have rarely been detected in field investigations, however may be due to the low recovery efficiency of the analytical methods. The scarcity of information on HCoV in the environment suggests that research is needed to understand the fate of these viruses in the water cycle.

Title: Implication of COVID‐19 in oral oncology practices in Brazil, Canada and the United States Content: The newly emerged Coronavirus disease 2019 (COVID‐19) is an infectious disease that has spread rapidly throughout the world. The most common signs and symptoms are fever, dry cough and shortness of breath which can progress to severe viral pneumonia and multi‐organ failure in susceptive patients (Chen et al. 2020, Wang et al. 2020). Droplet transmission and person‐person transmission appear to be the main route of transmission of COVID‐19, however asymptomatic patients are also carriers of the virus (Rothe et al. 2020).

Title: Ocular conjunctival inoculation of SARS-CoV-2 can cause mild COVID-19 in Rhesus macaques Content: The outbreak of Corona Virus Disease 2019 caused by the severe acute respiratory syndrome coronavirus (SARS-CoV-2) is highly transmitted. The potential extra-respiratory transmission routes remain uncertain. Five rhesus macaques were inoculated with 1×106 TCID50 of SARS-CoV-2 via conjunctival (CJ), intratracheal (IT), and intragastric (IG) routes, respectively. Remarkably, the CJ inoculated-macaques developed mild interstitial pneumonia and viral load was detectable in the conjunctival swabs at 1 days post-inoculation (dpi). Only via IT inoculation, viral load was detected in the anal swab at 1-7 dpi and macaque showed weight loss. However, viral load was undetectable after IG inoculation. Comparatively, viral load was higher in the nasolacrimal system but lesions of lung were relatively mild and local via CJ inoculation compared with that via IT inoculation, demonstrating distinct characteristics of virus dispersion. Both the two routes affected the alimentary tract. Therefore the clinicians need to protect eye while working with patients.

Title: Transmission dynamics of coronavirus disease 2019 outside of Daegu-Gyeongsangbuk provincial region in South Korea Content: We analyzed transmission of coronavirus disease 2019 in South Korea. We estimated that non-pharamaceutical measures reduced the immediate transmissibility by maximum of 34% for coronavirus disease 2019. Continuous efforts are needed for monitoring the transmissibility to optimize epidemic control.

Title: Is SARS-CoV-2 Also an Enteric Pathogen With Potential Fecal-Oral Transmission? A COVID-19 Virological and Clinical Review Content: In as few as 3 months, coronavirus disease 2019 (COVID-19) has spread and ravaged the world at an unprecedented speed in modern history, rivaling the 1918 flu pandemic. Severe acute respiratory syndrome coronavirus-2, the culprit virus, is highly contagious and stable in the environment and transmits predominantly among humans via the respiratory route. Accumulating evidence suggest that this virus, like many of its related viruses, may also be an enteric virus that can spread via the fecal-oral route. Such a hypothesis would also contribute to the rapidity and proliferation of this pandemic. Here we briefly summarize what is known about this family of viruses and literature basis of the hypothesis that severe acute respiratory syndrome coronavirus-2 is capable of infecting the gastrointestinal tract and shedding in the environment for potential human-to-human transmission.

Title: [Replication and transmission mechanisms of highly pathogenic human coronaviruses] Content: The three known human highly pathogenic coronaviruses are severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus, (MERS-CoV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Human highly pathogenic coronaviruses are composed of non-structural proteins, structural proteins and accessory proteins Viral particles recognize host receptors via spike glycoprotein (S protein), enter host cells by membrane fusion, replicate in host cells through large replication-transcription complexes, and promote proliferation by interfering with and suppressing the host's immune response Human highly pathogenic coronaviruses are hosted by humans and vertebrates Viral particles are transmitted through droplets, contact and aerosols or likely through digestive tract, urine, eyes and other routes This review discusses the mechanisms of proliferation and transmission of highly pathogenic human coronaviruses based on the results of existing research, providing basis for future study on interrupting the transmission and pathogenicity of human highly pathogenic coronaviruses

Title: Mechano-genomic regulation of coronaviruses and its interplay with ageing Content: Coronaviruses employ various nuclear signalling mechanisms for their propagation. Here we link replication of coronaviruses, including SARS-CoV-2, the coronavirus disease 2019 (COVID-19)-causing virus, with cytoskeleton-dependent signalling and 3D genome organization. This link could provide novel insights into the high coronavirus pathogenicity in certain cellular states, particularly those associated with ageing.

Title: Differential diagnosis of illness in patients under investigation for the novel coronavirus (SARS-CoV-2), Italy, February 2020 Content: A novel coronavirus (SARS-CoV-2) has been identified as the causative pathogen of an ongoing outbreak of respiratory disease, now named COVID-19. Most cases and sustained transmission occurred in China, but travel-associated cases have been reported in other countries, including Europe and Italy. Since the symptoms are similar to other respiratory infections, differential diagnosis in travellers arriving from countries with wide-spread COVID-19 must include other more common infections such as influenza and other respiratory tract diseases.

Title: Coronavirus Host Range Expansion and Middle East Respiratory Syndrome Coronavirus Emergence: Biochemical Mechanisms and Evolutionary Perspectives. Content: Coronaviruses have frequently expanded their host range in recent history, with two events resulting in severe disease outbreaks in human populations. Severe acute respiratory syndrome coronavirus (SARS-CoV) emerged in 2003 in Southeast Asia and rapidly spread around the world before it was controlled by public health intervention strategies. The 2012 Middle East respiratory syndrome coronavirus (MERS-CoV) outbreak represents another prime example of virus emergence from a zoonotic reservoir. Here, we review the current knowledge of coronavirus cross-species transmission, with particular focus on MERS-CoV. MERS-CoV is still circulating in the human population, and the mechanisms governing its cross-species transmission have been only partially elucidated, highlighting a need for further investigation. We discuss biochemical determinants mediating MERS-CoV host cell permissivity, including virus spike interactions with the MERS-CoV cell surface receptor dipeptidyl peptidase 4 (DPP4), and evolutionary mechanisms that may facilitate host range expansion, including recombination, mutator alleles, and mutational robustness. Understanding these mechanisms can help us better recognize the threat of emergence for currently circulating zoonotic strains.

Title: Emerging novel coronavirus (2019-nCoV)-current scenario, evolutionary perspective based on genome analysis and recent developments Content: Coronaviruses are the well-known cause of severe respiratory, enteric and systemic infections in a wide range of hosts including man, mammals, fish, and avian. The scientific interest on coronaviruses increased after the emergence of Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) outbreaks in 2002-2003 followed by Middle East Respiratory Syndrome CoV (MERS-CoV). This decade's first CoV, named 2019-nCoV, emerged from Wuhan, China, and declared as 'Public Health Emergency of International Concern' on January 30th, 2020 by the World Health Organization (WHO). As on February 4, 2020, 425 deaths reported in China only and one death outside China (Philippines). In a short span of time, the virus spread has been noted in 24 countries. The zoonotic transmission (animal-to-human) is suspected as the route of disease origin. The genetic analyses predict bats as the most probable source of 2019-nCoV though further investigations needed to confirm the origin of the novel virus. The ongoing nCoV outbreak highlights the hidden wild animal reservoir of the deadly viruses and possible threat of spillover zoonoses as well. The successful virus isolation attempts have made doors open for developing better diagnostics and effective vaccines helping in combating the spread of the virus to newer areas.

Title: Limbic encephalitis after inhalation of a murine coronavirus. Content: The spread of a neurotropic coronavirus, mouse hepatitis virus strain A59, in the mouse central nervous system was studied after intranasal inoculation. Mouse hepatitis virus strain A59 spread during the 3- to 5-day postinoculation period, through the olfactory pathway into the limbic system. Coronavirus particles were detected in the limbic system by electron microscopy. The combination of temporal propagation through an anatomical-physiological central nervous system pathway and anatomical restriction of viral infection suggests that specific interneuronal transport is important in spread of the virus. This experimental system may represent a model for diseases associated with human coronaviruses (common cold viruses) and/or the human limbic system.

Title: The impact of the SARS‐CoV‐2 outbreak on the safety and availability of blood transfusions in Italy Content: Coronaviruses are enveloped single-stranded RNA viruses belonging to the family of Coronaviridae. While initial research focused on their ability to cause enzootic infections, infections which have emerged in the past two decades demonstrate their ability to cross the species barrier and infect humans [1,2]. The ensuing epidemics have included Severe Acute Respiratory Syndrome (SARS) in 2002 and the more recent Middle East Respiratory Syndrome (MERS) in 2012, and have resulted in severe disease burden, mortality and economic disruption [3]. A novel flu-like coronavirus, emerging towards the end of 2019 and subsequently named SARS-CoV-2, has been associated with an epidemic initially focused in Wuhan, China.

Title: Progress in cross-species transmission of human coronaviruses (HCoVs)/ 人冠状病毒跨种传播的研究进展 Content: Coronaviruses (CoVs) are a group of ancient and common viruses, posing a severe threat to the health of humans and other animals. Currently, seven human CoVs (HCoVs) have been identified. They are all animal-derived zoonotic pathogens that jump the species barrier from their natural host animals to humans in a direct or indirect manner and lead to interpersonal transmission. The receptor binding domain (RBD) on the S1 subunit of CoV spike (S) protein is one of the key factors determining the cross-species transmission and the invasion potential. This review summarized and analyzed the transmission modes of seven HCoVs and the available structures of HCoV-RBD that mediated the cross-species transmission in order to better understanding the mechanism of CoV cross-species transmission and providing valuable knowledge in response to the potential cross-species transmission of novel CoVs in the future.

Title: Chapter 7 Coronaviridae: 100,000 Years of Emergence and Reemergence Content: Abstract The coronavirus family (Coronaviridae) is a positive-sense single-stranded RNA, with a size of 27kb. These viruses have a potential species specificity and interspecies transmission. The interspecies transmission of viruses from one host species to another is a major factor responsible for the majority of emerging and reemerging infections. The Coronaviridae is one of the most popular emerging viral families that threaten to the public health.

Title: COVID-19: Transmission, prevention, and potential therapeutic opportunities Content: The novel coronavirus disease (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), remains a global challenge. Despite intense research efforts worldwide, an effective vaccine and viable treatment options have eluded investigators. Therefore, infection prevention, early viral detection and identification of successful treatment protocols provide the best approach in controlling disease spread. In this review, current therapeutic options, preventive methods and transmission routes of COVID-19 are discussed.

Title: Coronaviruses: General Features Content: Coronaviruses have the largest known RNA genomes (∼30kb), which are of positive sense. Together with toroviruses, they are classified in the family Coronaviridae, order Nidovirales. All coronaviruses have four common proteins, three in the envelope and one associated with the genome. Assembly of virus particles occurs at internal membranes. The genes for the structural proteins are at the 3′ end of the genome. Most of the genome (∼20kb) is gene 1, which encodes 15–16 proteins associated with RNA replication and transcription. Translation of gene 1 involves ribosomal frameshifting. Transcription is by a discontinuous process which results in a 3′ co-terminal nested set of mRNAs, each of which has a common leader sequence transcribed from the 5′ terminus of the genome. Only the most 5′-proximal gene of each mRNA is translated. Recombination is a feature of coronavirus evolution. The outbreak of severe acute respiratory syndrome (SARS) has resulted in the discovery of more coronaviruses in humans, other mammals, and avian species, and the realization that the host range of coronaviruses is wider than previously acknowledged. Coronaviruses are associated with a wide range of diseases, including the respiratory and enteric systems, though not necessarily restricted to these, for example, some coronaviruses affect the central nervous system, kidneys, and gonads. The most widely used coronavirus vaccine (billions of doses annually) is against infectious bronchitis virus, which affects chickens.

Title: Coping With COVID-19: Learning From Past Pandemics to Avoid Pitfalls and Panic Content: It is imperative to concur on the main transmission routes of COVID-19 to explain risk and determine the most effective means to reduce illness and mortality. We must avoid generating irrational fear and maintain a broader perspective in the pandemic response, including assessing the possibility for substantial unintended consequences.

Title: Passengers' destinations from China: low risk of Novel Coronavirus (2019-nCoV) transmission into Africa and South America Content: Novel Coronavirus (2019-nCoV [SARS-COV-2]) was detected in humans during the last week of December 2019 at Wuhan city in China, and caused 24 554 cases in 27 countries and territories as of 5 February 2020. The objective of this study was to estimate the risk of transmission of 2019-nCoV through human passenger air flight from four major cities of China (Wuhan, Beijing, Shanghai and Guangzhou) to the passengers' destination countries. We extracted the weekly simulated passengers' end destination data for the period of 1-31 January 2020 from FLIRT, an online air travel dataset that uses information from 800 airlines to show the direct flight and passengers' end destination. We estimated a risk index of 2019-nCoV transmission based on the number of travellers to destination countries, weighted by the number of confirmed cases of the departed city reported by the World Health Organization (WHO). We ranked each country based on the risk index in four quantiles (4th quantile being the highest risk and 1st quantile being the lowest risk). During the period, 388 287 passengers were destined for 1297 airports in 168 countries or territories across the world. The risk index of 2019-nCoV among the countries had a very high correlation with the WHO-reported confirmed cases (0.97). According to our risk score classification, of the countries that reported at least one Coronavirus-infected pneumonia (COVID-19) case as of 5 February 2020, 24 countries were in the 4th quantile of the risk index, two in the 3rd quantile, one in the 2nd quantile and none in the 1st quantile. Outside China, countries with a higher risk of 2019-nCoV transmission are Thailand, Cambodia, Malaysia, Canada and the USA, all of which reported at least one case. In pan-Europe, UK, France, Russia, Germany and Italy; in North America, USA and Canada; in Oceania, Australia had high risk, all of them reported at least one case. In Africa and South America, the risk of transmission is very low with Ethiopia, South Africa, Egypt, Mauritius and Brazil showing a similar risk of transmission compared to the risk of any of the countries where at least one case is detected. The risk of transmission on 31 January 2020 was very high in neighbouring Asian countries, followed by Europe (UK, France, Russia and Germany), Oceania (Australia) and North America (USA and Canada). Increased public health response including early case recognition, isolation of identified case, contract tracing and targeted airport screening, public awareness and vigilance of health workers will help mitigate the force of further spread to naïve countries.

Title: Passengers' destinations from China: low risk of Novel Coronavirus (2019-nCoV) transmission into Africa and South America Content: Novel Coronavirus (2019-nCoV [SARS-COV-2]) was detected in humans during the last week of December 2019 at Wuhan city in China, and caused 24 554 cases in 27 countries and territories as of 5 February 2020. The objective of this study was to estimate the risk of transmission of 2019-nCoV through human passenger air flight from four major cities of China (Wuhan, Beijing, Shanghai and Guangzhou) to the passengers' destination countries. We extracted the weekly simulated passengers' end destination data for the period of 1–31 January 2020 from FLIRT, an online air travel dataset that uses information from 800 airlines to show the direct flight and passengers' end destination. We estimated a risk index of 2019-nCoV transmission based on the number of travellers to destination countries, weighted by the number of confirmed cases of the departed city reported by the World Health Organization (WHO). We ranked each country based on the risk index in four quantiles (4(th) quantile being the highest risk and 1(st) quantile being the lowest risk). During the period, 388 287 passengers were destined for 1297 airports in 168 countries or territories across the world. The risk index of 2019-nCoV among the countries had a very high correlation with the WHO-reported confirmed cases (0.97). According to our risk score classification, of the countries that reported at least one Coronavirus-infected pneumonia (COVID-19) case as of 5 February 2020, 24 countries were in the 4(th) quantile of the risk index, two in the 3(rd) quantile, one in the 2(nd) quantile and none in the 1(st) quantile. Outside China, countries with a higher risk of 2019-nCoV transmission are Thailand, Cambodia, Malaysia, Canada and the USA, all of which reported at least one case. In pan-Europe, UK, France, Russia, Germany and Italy; in North America, USA and Canada; in Oceania, Australia had high risk, all of them reported at least one case. In Africa and South America, the risk of transmission is very low with Ethiopia, South Africa, Egypt, Mauritius and Brazil showing a similar risk of transmission compared to the risk of any of the countries where at least one case is detected. The risk of transmission on 31 January 2020 was very high in neighbouring Asian countries, followed by Europe (UK, France, Russia and Germany), Oceania (Australia) and North America (USA and Canada). Increased public health response including early case recognition, isolation of identified case, contract tracing and targeted airport screening, public awareness and vigilance of health workers will help mitigate the force of further spread to naïve countries.

Title: Tracing the SARS-coronavirus. Content: Four coronaviruses (HCoV-229E, HCoV-OC43, HCoV-NL63, HCoV-HKU1) are endemic in humans and mainly associated with mild respiratory illnesses; whereas the other two coronaviruses [Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) and Middle East Respiratory Syndrome Coronavirus (MERS-CoV)] present as emerging infections causing severe respiratory syndrome. Coronaviruses evolve by accumulation of point mutations and recombination of genomes among different strains or species. Mammalian coronaviruses including those infect humans are evolved from bat coronaviruses. While SARS-CoV and MERS-CoV are genetically closely related to bat coronaviruses, intermediate host(s) is (are) likely to be involved in the emergence and cross-species transmission of these novel human viruses. High prevalence of SARS-like coronaviruses have been found from masked palm civet cats and raccoon dogs collected from markets around the time of outbreaks in humans, but these animals are likely to be a transient accidental host rather than a persisting reservoir. More research is needed to elucidate the ecology of coronaviruses. Vigilance and surveillance should be maintained to promptly identify newly emerged coronaviruses.

Title: Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2): An Update Content: Coronaviruses (CoVs) belong to the family of Coronaviridae, the order Nidovirales, and the genus Coronavirus. They are the largest group of viruses causing respiratory and gastrointestinal infections. Morphologically, CoVs are enveloped viruses containing a non-segmented positive-sense, single-stranded ribonucleic acid (RNA) viruses. CoVs are categorized into four important genera that include Alphacoronavirus, Betacoronavirus, Gammacoronavirus, and Deltacoronavirus. A novel member of human CoV that has recently emerged in Wuhan, China, is now formally named as SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2). This is a unique strain of RNA viruses that have not been previously observed in humans. The virus has wide host adaptability and is capable of causing severe diseases in humans, masked palm civets, mice, dogs, cats, camels, pigs, chickens, and bats. The SARS-CoV-2 typically causes respiratory and gastrointestinal sickness in both humans and animals. It can be transmitted through aerosols and direct/indirect contact, as well as during medical cases and laboratory sample handling. Specific structural proteins, which might be found on the surface of the virus, play an important role in the pathogenesis and development of the complications. The disease is characterized by distinct medical signs and symptoms that include high fever, chills, cough, and shortness of breath or difficulty in breathing. The infected people may also present with other symptoms such as diarrhea, myalgia, fatigue, expectoration, and hemoptysis. It is important from the public health and economic point of view as it affects the growth of the country, which is majorly attributed to the restriction in the movement of the people and the cost associated with the control and prevention of the disease. Since there is no specific therapeutic intervention nor a vaccine available against the virus, supportive management and treatment with non-specific therapeutic agents (repurposed drugs) may provide relief to the patients. Some preventive strategies of the disease include blocking the routes of transmission of the infections, disinfection of instruments used during medical case handling, using personal protective equipment, proper and early diagnosis of the disease, avoiding contact with the sick patients, and quarantine of the infected/exposed people.

Title: Potential Fecal Transmission of SARS-CoV-2: Current Evidence and Implications for Public Health Content: Abstract Coronavirus disease 2019 (COVID-19) emerged in Hubei Province, China in December 2019 and has since become a global pandemic, with hundreds of thousands of cases and over 165 affected countries. Primary routes of transmission of the causative virus, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), are through respiratory droplets and close person-to-person contact. While information about other potential modes of transmission are relatively sparse, evidence supporting the possibility of a fecally-mediated mode of transmission has been accumulating. Here, current knowledge on the potential for fecal transmission is briefly reviewed and the possible implications are discussed from a public health perspective.

Title: Severe Acute Respiratory Syndrome Historical, Epidemiologic, and Clinical Features Content: Severe acute respiratory syndrome coronavirus (SARS-CoV), emerged from China and rapidly spread worldwide. Over 8098 people fell ill and 774 died before the epidemic ended in July 2003. Bats are likely an important reservoir for SARS-CoV. SARS-like CoVs have been detected in horseshoe bats and civet cats. The main mode of transmission of SARS-CoV is through inhalation of respiratory droplets. Faeco-oral transmission has been recorded. Strict infection control procedures with respiratory and contact precautions are essential. Fever and respiratory symptoms predominate, and diarrhea is common. Treatment involves supportive care. There are no specific antiviral treatments or vaccines available.

Title: Hand disinfection in the combat against Covid‐19 Content: The World Health Organization (WHO) has declared a global health emergency over a new coronavirus. The new corona virus (SARS‐CoV‐2) has raised global attention with raising concerns of rapid spread from human‐to‐human. Like severe acute respiratory syndrome (SARS)‐nCoV, 2019‐nCoV can be passed directly from person to person by respiratory droplets, and may also be transmitted through contact and fomites.

Title: COVID-19 pandemic: Impact of lockdown, contact and non-contact transmissions on infection dynamics Content: COVID-19 coronavirus pandemic has virtually locked down the entire world of human population, and through its rapid and unstoppable spread COVID-19 has essentially compartmentalised the population merely into susceptible, exposed, infected and recovered classes. Adapting the classical epidemic modelling framework, two distinct routes of COVID-19 transmission are incorporated into a model: (a) direct person-to-person contact transmission, and (b) indirect airborne and fomites-driven transmission. The indirect non-contact transmission route needs to explored in models of COVID-19 spread, because evidences show that this route of transmission is entirely viable with hugely uncertain level of relative contribution. This theoretical study based on model simulations demonstrates the following: (1) Not incorporating indirect transmission route in the model leads to underestimation of the basic reproduction number, and hence will impact on the COVID-19 mitigation decisions; (2) Lockdown measures can suppress the primary infection peak, but will lead to a secondary peak whose relative strength and time of occurrence depend on the success and duration of the lockdown measures; (3) To make lockdown effective, a considerable level of reduction in both contact and non-contact transmission rates over a long period is required; (4) To bring down the infection cases below any hypothetical health-care capacity, reduction of non-contact transmission rate is key, and hence active measures should be taken to reduce non-contact transmission (e.g., extensive uses of areal and aerosol disinfectant in public spaces to improve contaminated surfaces and air); (5) Any premature withdrawal of lockdown following the sign of a brief retracement in the infection cases can backfire, and can lead to a quicker, sharper and higher secondary peak, due to reactivation of the two transmission routes. Based on these results, this study recommends that any exit policy from lockdown, should take into account the level of transmission reduction in both routes, the absolute scale of which will vary among countries depending on their health-service capacity, but should be computed using accurate time-series data on infection cases and transmission rates.

Title: Public Health Response to the Initiation and Spread of Pandemic COVID-19 in the United States, February 24-April 21, 2020 Content: From January 21 through February 23, 2020, a total of 14 cases of coronavirus disease 2019 (COVID-19) were diagnosed in six U.S. states, including 12 cases in travelers arriving from China and two in household contacts of persons with confirmed infections. An additional 39 cases were identified in persons repatriated from affected areas outside the United States (1). Starting in late February, reports of cases with no recent travel to affected areas or links to known cases signaled the initiation of pandemic spread in the United States (2). By mid-March, transmission of SARS-CoV-2, the virus that causes COVID-19, had accelerated, with rapidly increasing case counts indicating established transmission in the United States. Ongoing traveler importation of SARS-CoV-2, attendance at professional and social events, introduction into facilities or settings prone to amplification, and challenges in virus detection all contributed to rapid acceleration of transmission during March. Public health responses included intensive efforts to detect cases and trace contacts, and implementation of multiple community mitigation strategies. Because most of the population remains susceptible to infection, recognition of factors associated with amplified spread during the early acceleration period will help inform future decisions as locations in the United States scale back some components of mitigation and strengthen systems to detect a potential transmission resurgence. U.S. circulation of SARS-CoV-2 continues, and sustained efforts will be needed to prevent future spread within the United States.

Title: Public Health Response to the Initiation and Spread of Pandemic COVID-19 in the United States, February 24-April 21, 2020. Content: From January 21 through February 23, 2020, a total of 14 cases of coronavirus disease 2019 (COVID-19) were diagnosed in six U.S. states, including 12 cases in travelers arriving from China and two in household contacts of persons with confirmed infections. An additional 39 cases were identified in persons repatriated from affected areas outside the United States (1). Starting in late February, reports of cases with no recent travel to affected areas or links to known cases signaled the initiation of pandemic spread in the United States (2). By mid-March, transmission of SARS-CoV-2, the virus that causes COVID-19, had accelerated, with rapidly increasing case counts indicating established transmission in the United States. Ongoing traveler importation of SARS-CoV-2, attendance at professional and social events, introduction into facilities or settings prone to amplification, and challenges in virus detection all contributed to rapid acceleration of transmission during March. Public health responses included intensive efforts to detect cases and trace contacts, and implementation of multiple community mitigation strategies. Because most of the population remains susceptible to infection, recognition of factors associated with amplified spread during the early acceleration period will help inform future decisions as locations in the United States scale back some components of mitigation and strengthen systems to detect a potential transmission resurgence. U.S. circulation of SARS-CoV-2 continues, and sustained efforts will be needed to prevent future spread within the United States.

Title: Active tuberculosis, sequelae and COVID-19 co-infection: first cohort of 49 cases Content: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease (COVID-19) pandemic has attracted interest because of its global rapid spread, clinical severity, high mortality rate, and capacity to overwhelm healthcare systems [1, 2]. SARS-CoV-2 transmission occurs mainly through droplets, although surface contamination contributes and debate continues on aerosol transmission [3–5].

Title: Is 0.5% Hydrogen Peroxide Effective against SARS‐CoV‐2? Content: SARS‐CoV‐2 is mostly transmitted through respiratory droplets and contact routes, but the WHO also states that “airborne transmission may be possible in specific circumstances and settings in which procedures or support treatments that generate aerosols are performed” (WHO, 2020).

Title: Avoiding COVID-19: Aerosol Guidelines Content: The COVID-19 pandemic has brought into sharp focus the need to understand respiratory virus transmission mechanisms. In preparation for an anticipated influenza pandemic, a substantial body of literature has developed over the last few decades showing that the short-range aerosol route is an important, though often neglected transmission path. We develop a simple mathematical model for COVID-19 transmission via aerosols, apply it to known outbreaks, and present quantitative guidelines for ventilation and occupancy in the workplace.

Title: COVID-19: Structural Predictions of Viral Success Content: Since the beginning of the 21st century, three coronaviruses have crossed the species barrier and caused serious human disease: severe acute respiratory syndrome coronavirus (SARS-CoV) in November 2002 [1, 2], Middle-East respiratory syndrome coronavirus (MERS-CoV) in 2012 [3, 4], and SARS-CoV-2 in 2019 [5, 6]. SARS-CoV-2 [7], initially called 2019-nCoV, is the etiological agent of COVID-19, a highly contagious infectious illness that was first reported in December 2019 in Wuhan, China and subsequently spread globally [8]. As of May 24, 2020, COVID-19 has caused >5,370,000 infections and >343,000 deaths worldwide [9].

Title: Covid‐19 and neurodegeneration. What can we learn from the past? Content: Coronaviridae (CoVs) are single stranded RNA viruses. βeta‐CoVs encompasses Bat coronavirus (BCoV), the human Severe Acute Respiratory Syndrome (SARS) virus and the Middle Eastern Respiratory Syndrome (MERS) virus. In December 2019, a new βeta‐CoVs was identified in Wuhan, China, SARS‐CoV‐2. The genome sequencing demonstrated a 79.5% and 96.2% identity to SARS‐CoV and a bat CoV genome, respectively, supporting the interspecies transmission and the origin of this new pandemia.

Title: CHAPTER 28 Coronaviridae Content: Publisher Summary Coronaviruses are ssRNA viruses that infect a wide range of mammalian and avian species; they are important causes of respiratory and enteric disease, encephalomyelitis, hepatitis, serositis, and vasculitis in domestic animals. In humans, coronaviruses are one of several groups of viruses that cause the common cold. The prototype of the family, avian infectious brochitis virus, is one of the most infectious of all viruses and causes an acute respiratory disease, which in young chicks can cause very high mortality. Outbreaks can be explosive, involving nearly every bird in the flock at about the same time, because of respiratory transmission and a very short incubation period. In many ways, transmissible gastroenteritis virus of swine and mouse hepatitis virus behave similarly, affecting young animals most severely, spreading very quickly to all animals at risk, and causing major economic losses before control strategies can be put into place. The strategy of expression of the coronavirus genome is unique. The input virion RNA molecule is translated directly, one of the products being an RNA polymerase that then transcribes a full-length (—) sense copy RNA, from which in turn is transcribed a 3′-coterminal nested set of subgenomic mRNAs. The nested set comprises six overlapping species of mRNAs that extend for different lengths from a common 3′ terminus. Only the unique sequence toward the 5′ end, which is not shared with the next smallest mRNA in the nested set, is translated, each product, therefore, being a unique protein.

Title: Coronaviruses fusion with the membrane and entry to the host cell Content: Coronaviruses (CoVs) are positive-strand RNA viruses with the largest genome among all RNA viruses. They are able to infect many host, such as mammals or birds. Whereas CoVs were identified 1930s, they became known again in 2003 as the agents of the Severe Acute Respiratory Syndrome (SARS). The spike protein is thought to be essential in the process of CoVs entry, because it is associated with the binding to the receptor on the host cell. It is also involved in cell tropism and pathogenesis. Receptor recognition is the crucial step in the infection. CoVs are able to bind a variety of receptors, although the selection of receptor remains unclear. Coronaviruses were initially believed to enter cells by fusion with the plasma membrane. Further studies demonstrated that many of them involve endocytosis through clathrin-dependent, caveolae-dependent, clathrin-independent, as well as caveolae-independent mechanisms. The aim of this review is to summarise current knowledge about coronaviruses, focussing especially on CoVs entry into the host cell. Advances in understanding coronaviruses replication strategy and the functioning of the replicative structures are also highlighted. The development of host-directed antiviral therapy seems to be a promising way to treat infections with SARS-CoV or other pathogenic coronaviruses. There is still much to be discovered in the inventory of pro- and anti-viral host factors relevant for CoVs replication. The latest pandemic danger, originating from China, has given our previously prepared work even more of topicality.

Title: Coronaviruses fusion with the membrane and entry to the host cell. Content: Coronaviruses (CoVs) are positive-strand RNA viruses with the largest genome among all RNA viruses. They are able to infect many host, such as mammals or birds. Whereas CoVs were identified 1930s, they became known again in 2003 as the agents of the Severe Acute Respiratory Syndrome (SARS). The spike protein is thought to be essential in the process of CoVs entry, because it is associated with the binding to the receptor on the host cell. It is also involved in cell tropism and pathogenesis. Receptor recognition is the crucial step in the infection. CoVs are able to bind a variety of receptors, although the selection of receptor remains unclear. Coronaviruses were initially believed to enter cells by fusion with the plasma membrane. Further studies demonstrated that many of them involve endocytosis through clathrin-dependent, caveolae-dependent, clathrin-independent, as well as caveolae-independent mechanisms. The aim of this review is to summarise current knowledge about coronaviruses, focussing especially on CoVs entry into the host cell. Advances in understanding coronaviruses replication strategy and the functioning of the replicative structures are also highlighted. The development of host-directed antiviral therapy seems to be a promising way to treat infections with SARS-CoV or other pathogenic coronaviruses. There is still much to be discovered in the inventory of pro- and anti-viral host factors relevant for CoVs replication. The latest pandemic danger, originating from China, has given our previously prepared work even more of topicality.

Title: Properties of Coronavirus and SARS-CoV-2 Content: were identified beginning with the discovery of SARS-CoV in 2002. With the recent detection of SARS-CoV-2, there are now seven human coronaviruses. Those that cause mild diseases are the 229E, OC43, NL63 and HKU1, and the pathogenic species are SARS-CoV, MERS-CoV and SARS-CoV-2 Coronaviruses (order Nidovirales, family Coronaviridae, and subfamily Orthocoronavirinae) are spherical (125nm diameter), and enveloped with club-shaped spikes on the surface giving the appearance of a solar corona. Within the helically symmetrical nucleocapsid is the large positive sense, single stranded RNA. Of the four coronavirus genera (α,ß,Î³,Î´), human coronaviruses (HCoVs) are classified under α-CoV (HCoV-229E and NL63) and ß-CoV (MERS-CoV, SARS-CoV, HCoVOC43 and HCoV-HKU1). SARS-CoV-2 is a ß-CoV and shows fairly close relatedness with two bat-derived CoV-like coronaviruses, bat-SL-CoVZC45 and bat-SL-CoVZXC21. Even so, its genome is similar to that of the typical CoVs. SARS-CoV and MERS-CoV originated in bats, and it appears to be so for SARS-CoV-2 as well. The possibility of an intermediate host facilitating the emergence of the virus in humans has already been shown with civet cats acting as intermediate hosts for SARS-CoVs, and dromedary camels for MERS-CoV. Human-to-human transmission is primarily achieved through close contact of respiratory droplets, direct contact with the infected individuals, or by contact with contaminated objects and surfaces. The coronaviral genome contains four major structural proteins: the spike (S), membrane (M), envelope (E) and the nucleocapsid (N) protein, all of which are encoded within the 3' end of the genome. The S protein mediates attachment of the virus to the host cell surface receptors resulting in fusion and subsequent viral entry. The M protein is the most abundant protein and defines the shape of the viral envelope. The E protein is the smallest of the major structural proteins and participates in viral assembly and budding. The N protein is the only one that binds to the RNA genome and is also involved in viral assembly and budding. Replication of coronaviruses begin with attachment and entry. Attachment of the virus to the host cell is initiated by interactions between the S protein and its specific receptor. Following receptor binding, the virus enters host cell cytosol via cleavage of S protein by a protease enzyme, followed by fusion of the viral and cellular membranes. The next step is the translation of the replicase gene from the virion genomic RNA and then translation and assembly of the viral replicase complexes. Following replication and subgenomic RNA synthesis, encapsidation occurs resulting in the formation of the mature virus. Following assembly, virions are transported to the cell surface in vesicles and released by exocytosis.

Title: Coronaviruses: An Overview of Their Replication and Pathogenesis Content: Coronaviruses (CoVs), enveloped positive-sense RNA viruses, are characterized by club-like spikes that project from their surface, an unusually large RNA genome, and a unique replication strategy. Coronaviruses cause a variety of diseases in mammals and birds ranging from enteritis in cows and pigs and upper respiratory disease chickens to potentially lethal human respiratory infections. Here we provide a brief introduction to coronaviruses discussing their replication and pathogenicity, and current prevention and treatment strategies. We will also discuss the outbreaks of the highly pathogenic Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) and the recently identified Middle Eastern Respiratory Syndrome Coronavirus (MERS-CoV).

Title: Coronaviruses Content: The members of coronavirus family are facultative pathogens of birds and mammals, including men. From their first isolation 60 years ago, they caused smaller or larger epidemics mainly originating from China. The most recent pandemic quickly spreading worldwide has affected over 2,000,000 people. Keywords: coronavirus; epidemic; single strand vRNA.

Title: Coronaviruses. Content: The members of coronavirus family are facultative pathogens of birds and mammals, including men. From their first isolation 60 years ago, they caused smaller or larger epidemics mainly originating from China. The most recent pandemic quickly spreading worldwide has affected over 2,000,000 people. Keywords: coronavirus; epidemic; single strand vRNA.

Title: 10 “C” in COVID19 Content: World war “C”(1) has set in against an invisible virus. The routes of transmission include *Contact of contaminated objects,*Circulating droplets in the air called aerosols disseminated through *Cough, sneeze, ocular secretions(2) from an infected individual.

Title: The Rheumatologist's Role in Covid-19. Content: The novel coronavirus (SARS-CoV-2) pandemic has spread rapidly throughout the planet. It is believed to have originated in the Wuhan province of China, but this highly contagious respiratory virus has spread to over 140 countries on 6 continents as of mid-March 2020 according to the World Health Organization (WHO). Worldwide, there have been over 164,000 cases identified and over 6,500 deaths attributed to the viral infection. As of March 15, 2020, there are over 3,700 confirmed cases and 68 deaths ascribed to Covid-19 (the disease caused by SARS-CoV-2) in the United States [https://www.livescience.com/coronavirus-updates-unitedstates.html].

Title: Pandemic Human Coronavirus – Characterization and Comparison of Selected Properties of Hcov-sars and Hcov-mers Content: It: Two Coronaviruses, HCoV-229E and HCoV-OC43, causing generally mild respiratory tract infections in humans, were described in the XX c Pandemic Coronaviruses were first discovered as late as in the XXI c : SARS-HCoV in 2002 – causing severe respiratory tract infections (SARS) in China;MERS-HCoV in 2012 – circulating mostly on the Arabian Peninsula The SARS epidemic ended in 2004 resulting in morbidity of >8000 and >770 deaths, while the MERS epidemic is still ongoing (>2000 ill, >700 deaths) although its intensity decreased Both viruses are zoonotic and require at least two “host jumps” for the transmission of the infection to humans: for HCoV-SARS – from bat to palm civet and then to human;for HCoV-MERS – from bats to camels and subsequently to humans Primary mode of transmission is droplet in close contact (<1 m), but both viruses remain active in aerosol (up to 24 h), so infection can be also spread by air (ventilation) The ability for human-to-human transmission is higher for HCoV-SARS than for HCoV-MERS (8 generations vs 4, respectively) Moreover, there are differences in genome structure and pathogenic mechanisms: different receptor, cell entry mechanism, different way of host response modulation (e g inhibition of IFNβ cascade), etc Probably, these differences influence the overall manifestation of the disease in humans Infection caused by HCoV-MERS might manifest itself as ARDS, a mild-mannered and asymptomatic disease HCoV-SARS infections seem to be associated with severe disease only In this paper, a comparison of the structure of these viruses, the mechanisms underlying their ability to cross the interspecies barrier and to multiply in the human body, including modulation of IFNβ cascade, as well as routes of infection transmission and symptoms caused, were presented

Title: Transmission of SARS-CoV-2: an update of current literature Content: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiologic agent for the 2019 coronavirus disease (COVID-19) pandemic, has caused a public health emergency. The need for additional research in viral pathogenesis is essential as the number of cases and deaths rise. Understanding the virus and its ability to cause disease has been the main focus of current literature; however, there is much unknown. Studies have revealed new findings related to the full transmission potential of SARS-CoV-2 and its subsequent ability to cause infection by different means. The virus is hypothesized to be of increased virulence compared with previous coronavirus that caused epidemics, in part due to its overall structural integrity and resilience to inactivation. To date, many studies have discussed that the rationale behind its transmission potential is that viral RNA has unexpectedly been detected in multiple bodily fluids, with some samples having remained positive for extended periods of time. Additionally, the receptor by which the virus gains cellular entry, ACE2, has been found to be expressed in different human body systems, thereby potentiating its infection in those locations. In this evidence-based comprehensive review, we discuss various potential routes of transmission of SARS-CoV-2—respiratory/droplet, indirect, fecal-oral, vertical, sexual, and ocular. Understanding these different routes is important as they pertain to clinical practice, especially in taking preventative measures to mitigate the spread of SARS-CoV-2.

Title: Tackling Corona Virus Disease 2019 (COVID 19) in Workplaces Content: Coronaviruses are zoonotic viruses and six species of Coronaviruses are known to cause human disease such as cause common cold, severe acute respiratory syndrome and the Middle East Respiratory Syndrome. In January 2020, scientists in Wuhan, China isolated a novel coronavirus (SARS-CoV-2), responsible for an outbreak of unknown pneumonia that had not been previously reported among humans. This virus spreads from person to person, through respiratory droplets, close contact, and by touching surfaces or objects contaminated by the virus. The incubation period varies between 2 days and 14 days. Symptoms usually include fever, cough, difficulty in breathing, pneumonia, severe acute respiratory syndrome. Older age and co-morbid conditions increase the fatality. Any person with a history of travel to and from COVID-19 affected countries in the past 14 days or any person who has had close contact with a laboratory confirmed COVID-19 are suspect cases and needs evaluation. Currently no vaccine is available and treatment is mainly supportive. Measures at workplace should include- avoiding non-essential travel, identifying and isolating sick employees at the earliest, hand hygiene, respiratory hygiene, environmental hygiene and social distancing.

Title: A Mathematical Model of the Evolution and Spread of Pathogenic Coronaviruses from Natural Host to Human Host Content: Coronaviruses are highly transmissible and are pathogenic viruses of the 21(st) century worldwide. In general, these viruses are originated in bats or rodents. At the same time, the transmission of the infection to the human host is caused by domestic animals that represent in the habitat the intermediate host. In this study, we review the currently collected information about coronaviruses and establish a model of differential equations with piecewise constant arguments to discuss the spread of the infection from the natural host to the intermediate, and from them to the human host, while we focus on the potential spillover of bat-borne coronaviruses. The local stability of the positive equilibrium point of the model is considered via the Linearized Stability Theorem. Besides, we discuss global stability by employing an appropriate Lyapunov function. To analyze the outbreak in early detection, we incorporate the Allee effect at time t and obtain stability conditions for the dynamical behavior. Furthermore, it is shown that the model demonstrates the Neimark-Sacker Bifurcation. Finally, we conduct numerical simulations to support the theoretical findings.

Title: [Editorial] Possibility of transmission through dogs being a contributing factor to the extreme Covid19 outbreak in North Italy Content: Covid19 origin and transmission to humans. Covid19 infection began in Wuhan (Hubei, China) in December, 2019. Although to date it is considered that Covid19 originates from bats (96.2% overall genome sequence identity) (1), the type of intermediate animals that caused the transmission to humans remains unknown (2-4). Zhou et al (1) mentioned that 'Direct contact with intermediate host animals or consumption of wild animals was suspected to be the main route of SARSCoV2 transmission. However, the source(s) and transmission routine(s) of SARSCoV2 remain elusive' (1).

Title: Post-donation COVID-19 identification in blood donors. Content: The coronavirus disease 19 (COVID-19) outbreak, which was characterized as a pandemic on 11 March 2020 by the WHO, started in December 2019 with the emergence of pneumonia cases of unknown cause in Wuhan, Hubei, China [1]. SARS-CoV-2, the causative agent of COVID-19, are enveloped, non-segmented, single stranded positive sense RNA viruses and are classified as a sister clade to the prototype human and bat severe acute respiratory syndrome coronaviruses (SARS-CoVs) of the species Severe acute respiratory syndrome-related coronavirus [2]. So far, no respiratory virus, including SARS-CoV and the Middle East Respiratory Syndrome (MERS)-CoV, has been confirmed as transfusion-transmissible [3,4].

Title: Properties of Coronavirus and SARS-CoV-2. Content: were identified beginning with the discovery of SARS-CoV in 2002. With the recent detection of SARS-CoV-2, there are now seven human coronaviruses. Those that cause mild diseases are the 229E, OC43, NL63 and HKU1, and the pathogenic species are SARS-CoV, MERS-CoV and SARS-CoV-2 Coronaviruses (order Nidovirales, family Coronaviridae, and subfamily Orthocoronavirinae) are spherical (125nm diameter), and enveloped with club-shaped spikes on the surface giving the appearance of a solar corona. Within the helically symmetrical nucleocapsid is the large positive sense, single stranded RNA. Of the four coronavirus genera (α,β,γ,δ), human coronaviruses (HCoVs) are classified under α-CoV (HCoV-229E and NL63) and β-CoV (MERS-CoV, SARS-CoV, HCoVOC43 and HCoV-HKU1). SARS-CoV-2 is a β-CoV and shows fairly close relatedness with two bat-derived CoV-like coronaviruses, bat-SL-CoVZC45 and bat-SL-CoVZXC21. Even so, its genome is similar to that of the typical CoVs. SARS-CoV and MERS-CoV originated in bats, and it appears to be so for SARS-CoV-2 as well. The possibility of an intermediate host facilitating the emergence of the virus in humans has already been shown with civet cats acting as intermediate hosts for SARS-CoVs, and dromedary camels for MERS-CoV. Human-to-human transmission is primarily achieved through close contact of respiratory droplets, direct contact with the infected individuals, or by contact with contaminated objects and surfaces. The coronaviral genome contains four major structural proteins: the spike (S), membrane (M), envelope (E) and the nucleocapsid (N) protein, all of which are encoded within the 3' end of the genome. The S protein mediates attachment of the virus to the host cell surface receptors resulting in fusion and subsequent viral entry. The M protein is the most abundant protein and defines the shape of the viral envelope. The E protein is the smallest of the major structural proteins and participates in viral assembly and budding. The N protein is the only one that binds to the RNA genome and is also involved in viral assembly and budding. Replication of coronaviruses begin with attachment and entry. Attachment of the virus to the host cell is initiated by interactions between the S protein and its specific receptor. Following receptor binding, the virus enters host cell cytosol via cleavage of S protein by a protease enzyme, followed by fusion of the viral and cellular membranes. The next step is the translation of the replicase gene from the virion genomic RNA and then translation and assembly of the viral replicase complexes. Following replication and subgenomic RNA synthesis, encapsidation occurs resulting in the formation of the mature virus. Following assembly, virions are transported to the cell surface in vesicles and released by exocytosis.

Title: Coronavirus Disease 2019: Coronaviruses and Blood Safety Content: With the outbreak of unknown pneumonia in Wuhan, China, in December 2019, a new coronavirus, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), aroused the attention of the entire world. The current outbreak of infections with SARS-CoV-2 is termed Coronavirus Disease 2019 (COVID-19). The World Health Organization declared COVID-19 in China as a Public Health Emergency of International Concern. Two other coronavirus infections-SARS in 2002-2003 and Middle East Respiratory Syndrome (MERS) in 2012-both caused severe respiratory syndrome in humans. All 3 of these emerging infectious diseases leading to a global spread are caused by ß-coronaviruses. Although coronaviruses usually infect the upper or lower respiratory tract, viral shedding in plasma or serum is common. Therefore, there is still a theoretical risk of transmission of coronaviruses through the transfusion of labile blood products. Because more and more asymptomatic infections are being found among COVID-19 cases, considerations of blood safety and coronaviruses have arisen especially in endemic areas. In this review, we detail current evidence and understanding of the transmission of SARS-CoV, MERS-CoV, and SARS-CoV-2 through blood products as of February 10, 2020, and also discuss pathogen inactivation methods on coronaviruses.

Title: Perioperative airway management in patients infected with COVID-19/ Manejo de la vía aérea en el perioperatorio de los pacientes infectados con COVID-19 Content: Coronavirus disease 2019 (COVID-19) is highly contagious. Transmission is predominantly by droplet spread. Procedures during the initial handling of the airway and critical areas can generate drops and aerosols that increase the risk of transmission. The aim of this paper is to review the recommendations and guidelines related to airway management in patient infected by SARS-Cov-2.

Title: Coronaviruses: Molecular Biology Content: Coronaviruses (CoVs) are enveloped, positive-strand RNA viruses with characteristic spike glycoproteins that project outward like the rays of the sun (corona – Latin for ‘crown’), when visualized by electron microscopy. CoV are classified, together with the toroviruses, in the family Coronaviridae and the order Nidovirales. All nidoviruses have a common genome organization and generate a nested set (nido – Latin for ‘nest’) of 3′ co-terminal mRNAs. CoVs have been isolated from a variety of species, including birds, livestock, domestic animals, and humans. CoV infections can cause respiratory, gastrointestinal, and neurologic disease, depending on the strain of the virus and the site of infection. Importantly, CoVs have been shown to cross species barriers and have emerged from animal reservoirs to infect humans and cause severe disease. The CoV responsible for an outbreak of severe acute respiratory disease (SARS-CoV) in 2002–03 likely originated as a bat coronavirus which, during replication in an intermediate host (such as the palm civet), evolved to be able to infect humans efficiently. SARS-CoV infected over 8000 people with approximately 10% mortality rate. The SARS-CoV outbreak was controlled by public health measures alone. However, emergence or re-emergence of CoV from animal reservoirs is a potential concern for public health.

Title: Being a front-line dentist during the Covid-19 pandemic: a literature review Content: Coronavirus is an enveloped virus with positive-sense single-stranded RNA. Coronavirus infection in humans mainly affects the upper respiratory tract and to a lesser extent the gastrointestinal tract. Clinical symptoms of coronavirus infections can range from relatively mild (similar to the common cold) to severe (bronchitis, pneumonia, and renal involvement). The disease caused by the 2019 novel coronavirus (2019-nCoV) was called Covid-19 by the World Health Organization in February 2020. Face-to-face communication and consistent exposure to body fluids such as blood and saliva predispose dental care workers at serious risk for 2019-nCoV infection. As demonstrated by the recent coronavirus outbreak, information is not enough. During dental practice, blood and saliva can be scattered. Accordingly, dental practice can be a potential risk for dental staff, and there is a high risk of cross-infection. This article addresses all information collected to date on the virus, in accordance with the guidelines of international health care institutions, and provides a comprehensive protocol for managing possible exposure to patients or those suspected of having coronavirus.

Title: What makes a foodborne virus: comparison between coronaviruses with human noroviruses Content: In order to answer the question whether coronaviruses (CoVs) can be transmitted via foods, this review made a comparison between CoVs with the most recognized foodborne virus, human noroviruses (NoVs). As a result, although CoVs indeed have shown the possibilities to remain infectious on foods and/or food packaging materials long enough (from several days to several weeks) to potentially cause transmission, they seem to be less persistent than NoVs towards common disinfection practices with alcohols, chlorine and ultraviolet (UV). More importantly, the chance of foodborne transmission of CoVs is considered low as CoVs mainly spread through the respiratory tract and there is no clear evidence showing CoVs can follow fecal-oral routes like human NoVs and other foodborne viruses.

Title: Axonal Transport Enables Neuron-to-Neuron Propagation of Human Coronavirus OC43. Content: Human coronaviruses (HCoVs) are recognized respiratory pathogens for which accumulating evidence indicates that in vulnerable patients the infection can cause more severe pathologies. HCoVs are not always confined to the upper respiratory tract and can invade the central nervous system (CNS) under still unclear circumstances. HCoV-induced neuropathologies in humans are difficult to diagnose early enough to allow therapeutic interventions. Making use of our already described animal model of HCoV neuropathogenesis, we describe the route of neuropropagation from the nasal cavity to the olfactory bulb and piriform cortex and then the brain stem. We identified neuron-to-neuron propagation as one underlying mode of virus spreading in cell culture. Our data demonstrate that both passive diffusion of released viral particles and axonal transport are valid propagation strategies used by the virus. We describe for the first time the presence along axons of viral platforms whose static dynamism is reminiscent of viral assembly sites. We further reveal that HCoV OC43 modes of propagation can be modulated by selected HCoV OC43 proteins and axonal transport. Our work, therefore, identifies processes that may govern the severity and nature of HCoV OC43 neuropathogenesis and will make possible the development of therapeutic strategies to prevent occurrences.IMPORTANCE Coronaviruses may invade the CNS, disseminate, and participate in the induction of neurological diseases. Their neuropathogenicity is being increasingly recognized in humans, and the presence and persistence of human coronaviruses (HCoV) in human brains have been proposed to cause long-term sequelae. Using our mouse model relying on natural susceptibility to HCoV OC43 and neuronal cell cultures, we have defined the most relevant path taken by HCoV OC43 to access and spread to and within the CNS toward the brain stem and spinal cord and studied in cell culture the underlying modes of intercellular propagation to better understand its neuropathogenesis. Our data suggest that axonal transport governs HCoV OC43 egress in the CNS, leading to the exacerbation of neuropathogenesis. Exploiting knowledge on neuroinvasion and dissemination will enhance our ability to control viral infection within the CNS, as it will shed light on underlying mechanisms of neuropathogenesis and uncover potential druggable molecular virus-host interfaces.

Title: Coronavirus nCOVID-19: A Pandemic Disease and the Saudi precautions Content: Now nCOVID-19 has a foothold in many countries, and the threat of a pandemic situation has risen. Recently a novel coronavirus (nCOVID-19) has first emerged in China, causing multiple symptoms in humans and closely related to those caused by SARS (Severe Acute Respiratory Syndrome) and MERS (Middle East Respiratory Syndrome). The nCOVID-19 has reported in Wuhan city of China has recently infected over six million people and at least 0.4 million confirmed deaths all over the world, while 2.8 million people has recovered from this deadly virus. Many instances of this respiratory syndrome coronavirus infection have already reported in more than 216 countries and territories. In contrast, the majority of cases reported in the USA, Brazil, Russia, Spain, UK, Italy, France and many more countries. In today's context, the coronavirus is one of the significant issues faced by the world with plenty of cases. In these circumstances, rapid reviews which recommended by WHO (World Health Organization), and these recommendations are very significant, helpful and cover current data with different preventive measures developed by the Saudi CDC (Saudi Centre for Disease Prevention and Control). This review article describes the possible modes of transmission so that proper preventive actions should be taking. Importantly, this work mentioned the animal reservoir through which may infect humans, and it must be identified to break the transmission chain. In additions, this review paper briefly discussed the spread of the coronavirus in the Arabian Peninsula and what precaution measures are in place by each country to limit the spreading of this virus. Taking into consideration the preventive measures by pharmacists as part of health care professions, however, the number of infected people, especially those with close contact with nCOVID-19 patients, are rise day by day and currently seems unstoppable.

Title: Better Safe than Sorry: Interventional Radiology Should Be Prepared for the Coronavirus Disease 2019 Pandemic Content: Coronavirus disease 2019 (COVID-19) is a viral pneumonia that has plagued the world for much of the first quarter of 2020 and was recently declared a global pandemic. The caregivers must be aware of the disease and take steps to curb its transmission within the premises of our care settings (hospitals/clinics). In this article, we suggest a few proactive steps that can be taken at the institutional and departmental levels to break the transmission chain.

Title: A Computer Simulation Study on novel Corona Virus Transmission among the People in a Queue Content: The World Health Organization (WHO) on March 11, 2020, has declared the novel Corona virus (COVID-19) outbreak a global pandemic. It is essential to understand how coronavirus transmits from one person to another and this knowledge will help protect the vulnerable and limit the spread of the Corona virus. The mode of respiratory transmission of Corona virus is not completely understood as of date. Using a computer simulation, this paper analyses the probability of spreading of Corona virus through air among the people who are standing in a queue. The parameters such as the diameter of the virus particle, room temperature, relative humidity, height of the person, distance between the people and the waiting time in the queue are considered in the computer model to determine the distribution of Corona virus and hence identify the risk factor of spreading the Covid-19. This paper describes the possibilities of getting infectious when a Covid-19 infected person present in a queue and the impact on the waiting time and the position in the queue on the transmission of Corona virus.

Title: Transmission and risk factors of OF COVID-19 Content: SARS-CoV-2, the virus that causes COVID-19, is transmitted through respiratory secretions and saliva. The virus can also live for short periods of time (1 to several hours) on fomites such as doorknobs, handrails, and tables. Aerosolization of the virus can occur during procedures including bronchoscopy, endotracheal intubation, and administration of nebulized treatments. Asymptomatic shedding of the virus does occur and may account for up to 60% of cases. Risk factors for a more severe course of COVID-19 include age 65 and older, living in a nursing home or long term care facility, chronic lung disease, and others.

Title: Transmission and risk factors of OF COVID-19. Content: SARS-CoV-2, the virus that causes COVID-19, is transmitted through respiratory secretions and saliva. The virus can also live for short periods of time (1 to several hours) on fomites such as doorknobs, handrails, and tables. Aerosolization of the virus can occur during procedures including bronchoscopy, endotracheal intubation, and administration of nebulized treatments. Asymptomatic shedding of the virus does occur and may account for up to 60% of cases. Risk factors for a more severe course of COVID-19 include age 65 and older, living in a nursing home or long term care facility, chronic lung disease, and others.

Title: Airborne transmission of severe acute respiratory syndrome coronavirus-2 to healthcare workers: a narrative review Content: Healthcare workers are at risk of infection during the severe acute respiratory syndrome coronavirus-2 pandemic. International guidance suggests direct droplet transmission is likely and airborne transmission occurs only with aerosol-generating procedures. Recommendations determining infection control measures to ensure healthcare worker safety follow these presumptions. Three mechanisms have been described for the production of smaller sized respiratory particles ('aerosols') that, if inhaled, can deposit in the distal airways. These include: laryngeal activity such as talking and coughing; high velocity gas flow; and cyclical opening and closure of terminal airways. Sneezing and coughing are effective aerosol generators, but all forms of expiration produce particles across a range of sizes. The 5-µm diameter threshold used to differentiate droplet from airborne is an over-simplification of multiple complex, poorly understood biological and physical variables. The evidence defining aerosol-generating procedures comes largely from low-quality case and cohort studies where the exact mode of transmission is unknown as aerosol production was never quantified. We propose that transmission is associated with time in proximity to severe acute respiratory syndrome coronavirus-1 patients with respiratory symptoms, rather than the procedures per se. There is no proven relation between any aerosol-generating procedure with airborne viral content with the exception of bronchoscopy and suctioning. The mechanism for severe acute respiratory syndrome coronavirus-2 transmission is unknown but the evidence suggestive of airborne spread is growing. We speculate that infected patients who cough, have high work of breathing, increased closing capacity and altered respiratory tract lining fluid will be significant producers of pathogenic aerosols. We suggest several aerosol-generating procedures may in fact result in less pathogen aerosolisation than a dyspnoeic and coughing patient. Healthcare workers should appraise the current evidence regarding transmission and apply this to the local infection prevalence. Measures to mitigate airborne transmission should be employed at times of risk. However, the mechanisms and risk factors for transmission are largely unconfirmed. Whilst awaiting robust evidence, a precautionary approach should be considered to assure healthcare worker safety.

Title: COVID-19: Emergence, Spread, Possible Treatments, and Global Burden Content: The Coronavirus (CoV) is a large family of viruses known to cause illnesses ranging from the common cold to acute respiratory tract infection. The severity of the infection may be visible as pneumonia, acute respiratory syndrome, and even death. Until the outbreak of SARS, this group of viruses was greatly overlooked. However, since the SARS and MERS outbreaks, these viruses have been studied in greater detail, propelling the vaccine research. On December 31, 2019, mysterious cases of pneumonia were detected in the city of Wuhan in China's Hubei Province. On January 7, 2020, the causative agent was identified as a new coronavirus (2019-nCoV), and the disease was later named as COVID-19 by the WHO. The virus spread extensively in the Wuhan region of China and has gained entry to over 210 countries and territories. Though experts suspected that the virus is transmitted from animals to humans, there are mixed reports on the origin of the virus. There are no treatment options available for the virus as such, limited to the use of anti-HIV drugs and/or other antivirals such as Remdesivir and Galidesivir. For the containment of the virus, it is recommended to quarantine the infected and to follow good hygiene practices. The virus has had a significant socio-economic impact globally. Economically, China is likely to experience a greater setback than other countries from the pandemic due to added trade war pressure, which have been discussed in this paper.

Title: Coronavirus Disease (COVID-19): Implications for Cardiovascular and Socially At-risk Populations Content: Dennison Himmelfarb and Baptiste discuss the implications of coronavirus disease (COVID-19) for cardiovascular and socially at-risk populations COVID-19 is an infectious respiratory disease caused by the newly discovered pathogen, SARS-CoV-2, a novel RNA-dependent RNA polymerase betacoronavirus that is thought to derive from bats At this time, there are no specific vaccines or treatments for COVID-19 The best way to prevent and slow transmission is to be well informed about the COVID-19 virus, the disease it causes, and how it spreads

Title: Coronaviruses: Molecular Biology☆ Content: Abstract Coronaviruses (CoVs) are enveloped, positive-strand RNA viruses with characteristic spike glycoproteins that project outward like the rays of the sun (corona – Latin for ‘crown’), when visualized by electron microscopy. CoV are classified, together with the toroviruses, in the family Coronaviridae and the order Nidovirales. All nidoviruses have a common genome organization and generate a nested set (nido – Latin for ‘nest’) of 3′ co-terminal mRNAs. CoVs have been isolated from a variety of species, including birds, livestock, domestic animals, and humans. CoV infections can cause respiratory, gastrointestinal, and neurologic disease, depending on the strain of the virus and the site of infection. Importantly, CoVs have been shown to cross species barriers and have emerged from animal reservoirs to infect humans and cause severe disease. The CoV responsible for an outbreak of severe acute respiratory disease (SARS-CoV) in 2002–03 likely originated as a bat coronavirus which, during replication in an intermediate host (such as the palm civet), evolved to be able to infect humans efficiently. SARS-CoV infected over 8000 people with approximately 10% mortality rate before it was controlled by public health measures of isolation of infected individuals and contacts. Middle East Respiratory Syndrome CoV (MERS-CoV), first reported in 2012, is likely transmitted from camels to humans with potentially fatal consequences. To date, there are no approved vaccines or direct acting antiviral drugs to combat coronavirus infections in humans. The emergence or re-emergence of CoVs from animal reservoirs is a potential concern for public health.

Title: Recombination, reservoirs, and the modular spike: mechanisms of coronavirus cross-species transmission. Content: Over the past 30 years, several cross-species transmission events, as well as changes in virus tropism, have mediated significant animal and human diseases. Most notable is severe acute respiratory syndrome (SARS), a lower respiratory tract disease of humans that was first reported in late 2002 in Guangdong Province, China. The disease, which quickly spread worldwide over a period of 4 months spanning late 2002 and early 2003, infected over 8,000 individuals and killed nearly 800 before it was successfully contained by aggressive public health intervention strategies. A coronavirus (SARS-CoV) was identified as the etiological agent of SARS, and initial assessments determined that the virus crossed to human hosts from zoonotic reservoirs, including bats, Himalayan palm civets (Paguma larvata), and raccoon dogs (Nyctereutes procyonoides), sold in exotic animal markets in Guangdong Province. In this review, we discuss the molecular mechanisms that govern coronavirus cross-species transmission both in vitro and in vivo, using the emergence of SARS-CoV as a model. We pay particular attention to how changes in the Spike attachment protein, both within and outside of the receptor binding domain, mediate the emergence of coronaviruses in new host populations.

Title: The role of environmental factors to transmission of SARS-CoV-2 (COVID-19) Content: The current outbreak of the novel coronavirus disease 2019 (COVID-19) in more than 250 countries has become a serious threat to the health of people around the world. Human-to-human transmission of the Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) occurs most often when people are in the incubation stage of the disease or are carriers and have no symptoms. Therefore, in this study, was discussed the role of environmental factors and conditions such as temperature, humidity, wind speed as well as food, water and sewage, air, insects, inanimate surfaces, and hands in COVID-19 transmission. The results of studies on the stability of the SARS-CoV-2 on different levels showed that the resistance of this virus on smooth surfaces was higher than others. Temperature increase and sunlight can facilitate the destruction of SARS-COV-2 and the stability of it on surfaces. When the minimum ambient air temperature increases by 1 °C, the cumulative number of cases decreases by 0.86%. According to the latest evidence, the presence of coronavirus in the sewer has been confirmed, but there is no evidence that it is transmitted through sewage or contaminated drinking water. Also, SARS-COV-2 transmission through food, food packages, and food handlers has not been identified as a risk factor for the disease. According to the latest studies, the possibility of transmitting SARS-COV-2 bioaerosol through the air has been reported in the internal environment of ophthalmology. The results additionally show that infectious bio-aerosols can move up to 6 feet. There have been no reports of SARS-COV-2 transmission by blood-feeding arthropods such as mosquitoes.

Title: Active Monitoring of Persons Exposed to Patients with Confirmed COVID-19 - United States, January-February 2020 Content: In December 2019, an outbreak of coronavirus disease 2019 (COVID-19), caused by the virus SARS-CoV-2, began in Wuhan, China (1). The disease spread widely in China, and, as of February 26, 2020, COVID-19 cases had been identified in 36 other countries and territories, including the United States. Person-to-person transmission has been widely documented, and a limited number of countries have reported sustained person-to-person spread.* On January 20, state and local health departments in the United States, in collaboration with teams deployed from CDC, began identifying and monitoring all persons considered to have had close contact with patients with confirmed COVID-19 (2). The aims of these efforts were to ensure rapid evaluation and care of patients, limit further transmission, and better understand risk factors for transmission.

Title: Comparison of transmissibility of coronavirus between symptomatic and asymptomatic patients: Reanalysis of the Ningbo Covid-19 data Content: We investigate the transmissibility of coronavirus for symptomatic and asymptomatic patients using the Ningbo Covid-19 data1. Through more in-depth and comprehensive statistical analysis, we conclude that there is no difference in the transmission rates of coronavirus between the symptomatic and asymptomatic patients, which is consistent with the original findings in Chen et al.1

Title: COVID‐19: Structural Predictions of Viral Success Content: Since the beginning of the 21(st) century, three coronaviruses have crossed the species barrier and caused serious human disease: severe acute respiratory syndrome coronavirus (SARS‐CoV) in November 2002 [1, 2], Middle‐East respiratory syndrome coronavirus (MERS‐CoV) in 2012 [3, 4], and SARS‐CoV‐2 in 2019 [5, 6]. SARS‐CoV‐2 [7], initially called 2019‐nCoV, is the etiological agent of COVID‐19, a highly contagious infectious illness that was first reported in December 2019 in Wuhan, China and subsequently spread globally [8]. As of May 24, 2020, COVID‐19 has caused >5,370,000 infections and >343,000 deaths worldwide [9].

Title: Active Monitoring of Persons Exposed to Patients with Confirmed COVID-19 - United States, January-February 2020. Content: In December 2019, an outbreak of coronavirus disease 2019 (COVID-19), caused by the virus SARS-CoV-2, began in Wuhan, China (1). The disease spread widely in China, and, as of February 26, 2020, COVID-19 cases had been identified in 36 other countries and territories, including the United States. Person-to-person transmission has been widely documented, and a limited number of countries have reported sustained person-to-person spread.* On January 20, state and local health departments in the United States, in collaboration with teams deployed from CDC, began identifying and monitoring all persons considered to have had close contact† with patients with confirmed COVID-19 (2). The aims of these efforts were to ensure rapid evaluation and care of patients, limit further transmission, and better understand risk factors for transmission.

Title: Household transmission of COVID-19, Shenzhen, January-February 2020 Content: Coronavirus disease 2019 has led to more than three million cases globally. Since the first family cluster of COVID-19 cases identified in Shenzhen in early January, most of the local transmission occurred within household contacts. Identifying the factors associated with household transmission is of great importance to guide preventive measures.

Title: Middle East Respiratory Syndrome Virus Pathogenesis Content: Coronaviruses (CoVs) are enveloped RNA viruses that infect birds, mammals, and humans. Infections caused by human coronaviruses (hCoVs) are mostly associated with the respiratory, enteric, and nervous systems. The hCoVs only occasionally induce lower respiratory tract disease, including bronchitis, bronchiolitis, and pneumonia. In 2002 to 2003, a global outbreak of severe acute respiratory syndrome (SARS) was the seminal detection of a novel CoV (SARS-CoV). A decade later (June 2012), another novel CoV was implicated as the cause of Middle East respiratory syndrome (MERS) in Saudi Arabia. Although bats might serve as a reservoir of MERS-CoV, it is unlikely that they are the direct source for most human cases. Severe lines of evidence suggest that dromedary camels have been the major cause of transmission to humans. The emergence of MERS-CoV has triggered serious concerns about the potential for a widespread outbreak. All MERS cases were linked directly or indirectly to the Middle East region including Saudi Arabia, Jordan, Qatar, Oman, Kuwait, and UAE. MERS cases have also been reported in the later phases in the United Kingdom, France, Germany, Italy, Spain, and Tunisia. Most of these MERS cases were linked with the Middle East. The high mortality rates in family-based and hospital-based outbreaks were reported among patients with comorbidities such as diabetes and renal failure. MERS-CoV causes an acute, highly lethal pneumonia and renal dysfunction. The major complications reported in fatal cases are hyperkalemia with associated ventricular tachycardia, disseminated intravascular coagulation, pericarditis, and multiorgan failure. The case-fatality rate seems to be higher for MERS-CoV (around 30%) than for SARS-CoV (9.6%). The combination regimen of type 1 interferon + lopinavir/ritonavir is considered as the first-line therapy for MERS. Antiviral treatment is generally recommended for 10 to 14 days in patients with MERS-CoV infection. Convalescent plasma therapy has shown some efficacy among patients refractory to antiviral drugs if administered within 2 weeks of the onset of the disease.