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2.
Cochrane Database Syst Rev ; 10: CD013717, 2020 10 05.
Article in English | MEDLINE | ID: covidwho-1557155

ABSTRACT

BACKGROUND: In late 2019, first cases of coronavirus disease 2019, or COVID-19, caused by the novel coronavirus SARS-CoV-2, were reported in Wuhan, China. Subsequently COVID-19 spread rapidly around the world. To contain the ensuing pandemic, numerous countries have implemented control measures related to international travel, including border closures, partial travel restrictions, entry or exit screening, and quarantine of travellers. OBJECTIVES: To assess the effectiveness of travel-related control measures during the COVID-19 pandemic on infectious disease and screening-related outcomes. SEARCH METHODS: We searched MEDLINE, Embase and COVID-19-specific databases, including the WHO Global Database on COVID-19 Research, the Cochrane COVID-19 Study Register, and the CDC COVID-19 Research Database on 26 June 2020. We also conducted backward-citation searches with existing reviews. SELECTION CRITERIA: We considered experimental, quasi-experimental, observational and modelling studies assessing the effects of travel-related control measures affecting human travel across national borders during the COVID-19 pandemic. We also included studies concerned with severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) as indirect evidence. Primary outcomes were cases avoided, cases detected and a shift in epidemic development due to the measures. Secondary outcomes were other infectious disease transmission outcomes, healthcare utilisation, resource requirements and adverse effects if identified in studies assessing at least one primary outcome. DATA COLLECTION AND ANALYSIS: One review author screened titles and abstracts; all excluded abstracts were screened in duplicate. Two review authors independently screened full texts. One review author extracted data, assessed risk of bias and appraised study quality. At least one additional review author checked for correctness of all data reported in the 'Risk of bias' assessment, quality appraisal and data synthesis. For assessing the risk of bias and quality of included studies, we used the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool for observational studies concerned with screening, ROBINS-I for observational ecological studies and a bespoke tool for modelling studies. We synthesised findings narratively. One review author assessed certainty of evidence with GRADE, and the review author team discussed ratings. MAIN RESULTS: We included 40 records reporting on 36 unique studies. We found 17 modelling studies, 7 observational screening studies and one observational ecological study on COVID-19, four modelling and six observational studies on SARS, and one modelling study on SARS and MERS, covering a variety of settings and epidemic stages. Most studies compared travel-related control measures against a counterfactual scenario in which the intervention measure was not implemented. However, some modelling studies described additional comparator scenarios, such as different levels of travel restrictions, or a combination of measures. There were concerns with the quality of many modelling studies and the risk of bias of observational studies. Many modelling studies used potentially inappropriate assumptions about the structure and input parameters of models, and failed to adequately assess uncertainty. Concerns with observational screening studies commonly related to the reference test and the flow of the screening process. Studies on COVID-19 Travel restrictions reducing cross-border travel Eleven studies employed models to simulate a reduction in travel volume; one observational ecological study assessed travel restrictions in response to the COVID-19 pandemic. Very low-certainty evidence from modelling studies suggests that when implemented at the beginning of the outbreak, cross-border travel restrictions may lead to a reduction in the number of new cases of between 26% to 90% (4 studies), the number of deaths (1 study), the time to outbreak of between 2 and 26 days (2 studies), the risk of outbreak of between 1% to 37% (2 studies), and the effective reproduction number (1 modelling and 1 observational ecological study). Low-certainty evidence from modelling studies suggests a reduction in the number of imported or exported cases of between 70% to 81% (5 studies), and in the growth acceleration of epidemic progression (1 study). Screening at borders with or without quarantine Evidence from three modelling studies of entry and exit symptom screening without quarantine suggests delays in the time to outbreak of between 1 to 183 days (very low-certainty evidence) and a detection rate of infected travellers of between 10% to 53% (low-certainty evidence). Six observational studies of entry and exit screening were conducted in specific settings such as evacuation flights and cruise ship outbreaks. Screening approaches varied but followed a similar structure, involving symptom screening of all individuals at departure or upon arrival, followed by quarantine, and different procedures for observation and PCR testing over a period of at least 14 days. The proportion of cases detected ranged from 0% to 91% (depending on the screening approach), and the positive predictive value ranged from 0% to 100% (very low-certainty evidence). The outcomes, however, should be interpreted in relation to both the screening approach used and the prevalence of infection among the travellers screened; for example, symptom-based screening alone generally performed worse than a combination of symptom-based and PCR screening with subsequent observation during quarantine. Quarantine of travellers Evidence from one modelling study simulating a 14-day quarantine suggests a reduction in the number of cases seeded by imported cases; larger reductions were seen with increasing levels of quarantine compliance ranging from 277 to 19 cases with rates of compliance modelled between 70% to 100% (very low-certainty evidence). AUTHORS' CONCLUSIONS: With much of the evidence deriving from modelling studies, notably for travel restrictions reducing cross-border travel and quarantine of travellers, there is a lack of 'real-life' evidence for many of these measures. The certainty of the evidence for most travel-related control measures is very low and the true effects may be substantially different from those reported here. Nevertheless, some travel-related control measures during the COVID-19 pandemic may have a positive impact on infectious disease outcomes. Broadly, travel restrictions may limit the spread of disease across national borders. Entry and exit symptom screening measures on their own are not likely to be effective in detecting a meaningful proportion of cases to prevent seeding new cases within the protected region; combined with subsequent quarantine, observation and PCR testing, the effectiveness is likely to improve. There was insufficient evidence to draw firm conclusions about the effectiveness of travel-related quarantine on its own. Some of the included studies suggest that effects are likely to depend on factors such as the stage of the epidemic, the interconnectedness of countries, local measures undertaken to contain community transmission, and the extent of implementation and adherence.


Subject(s)
COVID-19/prevention & control , Pandemics/prevention & control , SARS-CoV-2 , Travel-Related Illness , COVID-19/epidemiology , Communicable Diseases, Imported/epidemiology , Communicable Diseases, Imported/prevention & control , Coronavirus Infections/epidemiology , Coronavirus Infections/prevention & control , Humans , Models, Theoretical , Observational Studies as Topic , Quarantine , Severe Acute Respiratory Syndrome/epidemiology , Severe Acute Respiratory Syndrome/prevention & control
8.
Int J Infect Dis ; 104: 198-206, 2021 Mar.
Article in English | MEDLINE | ID: covidwho-1385702

ABSTRACT

INTRODUCTION: Synthesis of the available evidence on the effectiveness of medical and cloth facemask use by the general public in community settings is required to learn lessons for future respiratory epidemics/pandemics. METHOD: Search terms relating to facemasks, infection and community settings were used for PubMed, the Cochrane Library Database and Google Scholar. A meta-analysis was conducted using a random-effects model. RESULTS: The review included 12 primary studies on the effectiveness of medical facemask use to prevent influenza, influenza-like illness, SARS-CoV, and SARS-CoV-2 transmission. The meta-analysis demonstrated that facemask use significantly reduces the risk of transmitting these respiratory infections (pooled OR = 0.66, 95% CI 0.54-0.81). Of the 12 studies, 10 clinical trials suggested that respiratory infection incidence is lower with high medical facemask compliance, early use and use in combination with intensive hand hygiene. One cohort study conducted during the SARS-CoV-2 pandemic demonstrated that facemasks are effective in reducing SARS-CoV-2 transmission when used before those who are infected develop symptoms. One case-control study reported that controls used medical facemasks more often than cases infected with SARS-CoV (p < 0.05). No primary study on cloth facemask effectiveness to prevent respiratory infection transmission was found. CONCLUSION: Based on the available evidence, medical facemask use by healthy and sick individuals is recommended for preventing respiratory infection transmission in community settings. Medical facemask effectiveness is dependent on compliance and utilization in combination with preventive measures such as intensive hand hygiene. No direct evidence is currently available in humans supporting the recommendation of cloth facemask use to prevent respiratory infection transmission.


Subject(s)
COVID-19/prevention & control , Influenza, Human/prevention & control , Masks , Pandemics/prevention & control , Respiratory Tract Infections/prevention & control , Severe Acute Respiratory Syndrome/prevention & control , COVID-19/transmission , COVID-19/virology , Case-Control Studies , Cohort Studies , Hand Hygiene , Humans , Influenza, Human/transmission , Influenza, Human/virology , Respiratory Tract Infections/transmission , Respiratory Tract Infections/virology , Severe Acute Respiratory Syndrome/transmission , Severe Acute Respiratory Syndrome/virology
9.
Science ; 373(6558): 991-998, 2021 08 27.
Article in English | MEDLINE | ID: covidwho-1295160

ABSTRACT

The emergence of severe acute respiratory syndrome coronavirus (SARS-CoV) in 2003 and SARS-CoV-2 in 2019 highlights the need to develop universal vaccination strategies against the broader Sarbecovirus subgenus. Using chimeric spike designs, we demonstrate protection against challenge from SARS-CoV, SARS-CoV-2, SARS-CoV-2 B.1.351, bat CoV (Bt-CoV) RsSHC014, and a heterologous Bt-CoV WIV-1 in vulnerable aged mice. Chimeric spike messenger RNAs (mRNAs) induced high levels of broadly protective neutralizing antibodies against high-risk Sarbecoviruses. By contrast, SARS-CoV-2 mRNA vaccination not only showed a marked reduction in neutralizing titers against heterologous Sarbecoviruses, but SARS-CoV and WIV-1 challenge in mice resulted in breakthrough infections. Chimeric spike mRNA vaccines efficiently neutralized D614G, mink cluster five, and the UK B.1.1.7 and South African B.1.351 variants of concern. Thus, multiplexed-chimeric spikes can prevent SARS-like zoonotic coronavirus infections with pandemic potential.


Subject(s)
Betacoronavirus/immunology , COVID-19 Vaccines/immunology , Coronavirus Infections/prevention & control , Spike Glycoprotein, Coronavirus/immunology , Vaccines, Synthetic/immunology , Viral Vaccines/immunology , Animals , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Betacoronavirus/physiology , COVID-19/prevention & control , Coronavirus Infections/immunology , Cross Protection , Cytokines/blood , Female , Immunity, Heterologous , Immunogenicity, Vaccine , Liposomes , Lung/pathology , Lung/virology , Mice , Mice, Inbred BALB C , Nanoparticles , Protein Domains , Recombinant Fusion Proteins , SARS Virus/immunology , SARS Virus/physiology , SARS-CoV-2/immunology , SARS-CoV-2/physiology , Severe Acute Respiratory Syndrome/prevention & control , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Virus Replication
10.
BMC Infect Dis ; 21(1): 577, 2021 Jun 15.
Article in English | MEDLINE | ID: covidwho-1274542

ABSTRACT

BACKGROUND: During outbreaks of emerging and re-emerging infections, the lack of effective drugs and vaccines increases reliance on non-pharmacologic public health interventions and behavior change to limit human-to-human transmission. Interventions that increase the speed with which infected individuals remove themselves from the susceptible population are paramount, particularly isolation and hospitalization. Ebola virus disease (EVD), Severe Acute Respiratory Syndrome (SARS), and Middle East Respiratory Syndrome (MERS) are zoonotic viruses that have caused significant recent outbreaks with sustained human-to-human transmission. METHODS: This investigation quantified changing mean removal rates (MRR) and days from symptom onset to hospitalization (DSOH) of infected individuals from the population in seven different outbreaks of EVD, SARS, and MERS, to test for statistically significant differences in these metrics between outbreaks. RESULTS: We found that epidemic week and viral serial interval were correlated with the speed with which populations developed and maintained health behaviors in each outbreak. CONCLUSIONS: These findings highlight intrinsic population-level changes in isolation rates in multiple epidemics of three zoonotic infections with established human-to-human transmission and significant morbidity and mortality. These data are particularly useful for disease modelers seeking to forecast the spread of emerging pathogens.


Subject(s)
Communicable Disease Control/methods , Communicable Diseases, Emerging/epidemiology , Communicable Diseases, Emerging/prevention & control , Disease Outbreaks , Health Behavior , Animals , Coronavirus Infections/epidemiology , Coronavirus Infections/prevention & control , Epidemics/prevention & control , Forecasting , Hemorrhagic Fever, Ebola/epidemiology , Hemorrhagic Fever, Ebola/prevention & control , Humans , Public Health , Severe Acute Respiratory Syndrome/epidemiology , Severe Acute Respiratory Syndrome/prevention & control , Zoonoses/epidemiology , Zoonoses/prevention & control
11.
Microbiol Immunol ; 64(1): 33-51, 2020 Jan.
Article in English | MEDLINE | ID: covidwho-1262996

ABSTRACT

The spike (S) protein of coronavirus, which binds to cellular receptors and mediates membrane fusion for cell entry, is a candidate vaccine target for blocking coronavirus infection. However, some animal studies have suggested that inadequate immunization against severe acute respiratory syndrome coronavirus (SARS-CoV) induces a lung eosinophilic immunopathology upon infection. The present study evaluated two kinds of vaccine adjuvants for use with recombinant S protein: gold nanoparticles (AuNPs), which are expected to function as both an antigen carrier and an adjuvant in immunization; and Toll-like receptor (TLR) agonists, which have previously been shown to be an effective adjuvant in an ultraviolet-inactivated SARS-CoV vaccine. All the mice immunized with more than 0.5 µg S protein without adjuvant escaped from SARS after infection with mouse-adapted SARS-CoV; however, eosinophilic infiltrations were observed in the lungs of almost all the immunized mice. The AuNP-adjuvanted protein induced a strong IgG response but failed to improve vaccine efficacy or to reduce eosinophilic infiltration because of highly allergic inflammatory responses. Whereas similar virus titers were observed in the control animals and the animals immunized with S protein with or without AuNPs, Type 1 interferon and pro-inflammatory responses were moderate in the mice treated with S protein with and without AuNPs. On the other hand, the TLR agonist-adjuvanted vaccine induced highly protective antibodies without eosinophilic infiltrations, as well as Th1/17 cytokine responses. The findings of this study will support the development of vaccines against severe pneumonia-associated coronaviruses.


Subject(s)
Adjuvants, Immunologic/pharmacology , Coronavirus Infections/prevention & control , Gold/chemistry , Immunoglobulin G/immunology , Lung/immunology , Metal Nanoparticles/chemistry , Severe Acute Respiratory Syndrome/prevention & control , Spike Glycoprotein, Coronavirus/immunology , Analysis of Variance , Animals , Antibodies, Viral/immunology , Chlorocebus aethiops , Coronavirus/immunology , Coronavirus Infections/immunology , Coronavirus Infections/virology , Cytokines/metabolism , Disease Models, Animal , Female , Immunization , Lung/pathology , Mice , Mice, Inbred BALB C , Recombinant Proteins/immunology , SARS Virus/immunology , Severe Acute Respiratory Syndrome/immunology , Severe Acute Respiratory Syndrome/virology , Spike Glycoprotein, Coronavirus/genetics , Toll-Like Receptors , Vaccination , Vaccines, Synthetic , Vero Cells , Viral Envelope Proteins/genetics , Viral Envelope Proteins/immunology , Viral Vaccines/immunology , Viral Vaccines/pharmacology , Viral Vaccines/therapeutic use
12.
Neonatal Netw ; 40(3): 175-182, 2021 May 01.
Article in English | MEDLINE | ID: covidwho-1259287

ABSTRACT

The novel coronavirus disease 2019 (COVID-19), appeared in the United States over 1 year ago. This virus has a wide range of presentations, from being asymptomatic to causing severe acute respiratory syndrome, which can lead to death. It has led to a worldwide effort to find effective treatments, from repurposed medications to new discoveries, as well as the push to develop effective vaccines. As the race to fight this pandemic unfolds, this column provides what is currently available to combat this virus, how it has been utilized in the pregnant population, and what data have been made available about how these treatments affect fetal development and the neonate.


Subject(s)
COVID-19/drug therapy , COVID-19/prevention & control , COVID-19/transmission , Infectious Disease Transmission, Vertical/prevention & control , Maternal Health Services/standards , Neonatal Nursing/standards , Severe Acute Respiratory Syndrome/drug therapy , Severe Acute Respiratory Syndrome/prevention & control , Adult , Antiviral Agents/therapeutic use , COVID-19/epidemiology , Female , Humans , Infant, Newborn , Male , Practice Guidelines as Topic , Severe Acute Respiratory Syndrome/epidemiology , Severe Acute Respiratory Syndrome/transmission , United States/epidemiology
13.
Glob Public Health ; 16(8-9): 1223-1236, 2021.
Article in English | MEDLINE | ID: covidwho-1199411

ABSTRACT

The rate of infectious disease outbreaks has been accelerating over the past two decades, from the SARS epidemic in 2003 to COVID-19 in 2020. Termed by some as the twenty-first century's first pandemic, SARS originated in China and alerted the country to the importance of public health and epidemic response. After SARS, China improved its health infrastructure and reformed its political and legal health governance system. The emergence of COVID-19 from Wuhan in late 2019 put those reforms to the test. This paper analyses China's public health and epidemic response policies from a historical perspective, tracing the evolution of Chinese public health policies after the SARS outbreak in 2003. This paper assesses China's response to COVID-19 and how post-SARS policy reforms, particularly in epidemic response, played out on the ground in Wuhan. What policies worked well? What were the challenges faced? Based on the policy analysis, this paper presents recommendations for how China can improve its epidemic response through strengthened infectious disease surveillance, more transparent political coordination, and expanded public health infrastructure.


Subject(s)
COVID-19 , Epidemics , Policy , Public Health , Severe Acute Respiratory Syndrome , COVID-19/epidemiology , COVID-19/prevention & control , China/epidemiology , Epidemics/prevention & control , Humans , Severe Acute Respiratory Syndrome/epidemiology , Severe Acute Respiratory Syndrome/prevention & control
14.
J Med Virol ; 93(2): 741-754, 2021 02.
Article in English | MEDLINE | ID: covidwho-1196488

ABSTRACT

Coronaviruses (CoVs) are nonsegmented, single-stranded, positive-sense RNA viruses highly pathogenic to humans. Some CoVs are known to cause respiratory and intestinal diseases, posing a threat to the global public health. Against this backdrop, it is of critical importance to develop safe and effective vaccines against these CoVs. This review discusses human vaccine candidates in any stage of development and explores the viral characteristics, molecular epidemiology, and immunology associated with CoV vaccine development. At present, there are many obstacles and challenges to vaccine research and development, including the lack of knowledge about virus transmission, pathogenesis, and immune response, absence of the most appropriate animal models.


Subject(s)
COVID-19 Vaccines/biosynthesis , COVID-19/prevention & control , Coronavirus Infections/prevention & control , Severe Acute Respiratory Syndrome/prevention & control , Spike Glycoprotein, Coronavirus/immunology , Animals , COVID-19/immunology , COVID-19/virology , Camelus , Coronavirus Infections/immunology , Coronavirus Infections/virology , Cricetulus , Disease Models, Animal , Humans , Macaca mulatta , Mice , Middle East Respiratory Syndrome Coronavirus/drug effects , Middle East Respiratory Syndrome Coronavirus/immunology , SARS Virus/drug effects , SARS Virus/immunology , SARS-CoV-2/drug effects , SARS-CoV-2/immunology , Severe Acute Respiratory Syndrome/immunology , Severe Acute Respiratory Syndrome/virology , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Vaccines, Subunit , Vaccines, Synthetic/biosynthesis , Vaccines, Virus-Like Particle/biosynthesis
16.
Cell Host Microbe ; 29(5): 806-818.e6, 2021 05 12.
Article in English | MEDLINE | ID: covidwho-1184886

ABSTRACT

Coronaviruses have caused several human epidemics and pandemics including the ongoing coronavirus disease 2019 (COVID-19). Prophylactic vaccines and therapeutic antibodies have already shown striking effectiveness against COVID-19. Nevertheless, concerns remain about antigenic drift in SARS-CoV-2 as well as threats from other sarbecoviruses. Cross-neutralizing antibodies to SARS-related viruses provide opportunities to address such concerns. Here, we report on crystal structures of a cross-neutralizing antibody, CV38-142, in complex with the receptor-binding domains from SARS-CoV-2 and SARS-CoV. Recognition of the N343 glycosylation site and water-mediated interactions facilitate cross-reactivity of CV38-142 to SARS-related viruses, allowing the antibody to accommodate antigenic variation in these viruses. CV38-142 synergizes with other cross-neutralizing antibodies, notably COVA1-16, to enhance neutralization of SARS-CoV and SARS-CoV-2, including circulating variants of concern B.1.1.7 and B.1.351. Overall, this study provides valuable information for vaccine and therapeutic design to address current and future antigenic drift in SARS-CoV-2 and to protect against zoonotic SARS-related coronaviruses.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/prevention & control , SARS Virus/immunology , SARS-CoV-2/immunology , Severe Acute Respiratory Syndrome/prevention & control , Angiotensin-Converting Enzyme 2/metabolism , Antibodies, Neutralizing/chemistry , Antibodies, Viral/chemistry , Cross Reactions , Humans , Spike Glycoprotein, Coronavirus/metabolism
18.
Fertil Steril ; 115(4): 831-839, 2021 04.
Article in English | MEDLINE | ID: covidwho-1131298

ABSTRACT

The coronavirus disease 2019 pandemic has resulted in many changes in how we interact in society, requiring that we protect ourselves and others from an invisible, airborne enemy called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Until a vaccine is developed, and it reaches high levels of distribution, everyone must continue to be diligent to limit the viral spread. The practice of assisted reproduction during this pandemic presents unique challenges in addition to the risks identified in general clinical care. The established good tissue practices employed in laboratories are not designed to protect gametes and embryos from an airborne virus, particularly one that may be shed by an asymptomatic staff member. Armed with theoretical risks but lacking direct evidence, assisted-reproduction teams must examine every aspect of their practice, identify areas at a risk of exposure to SARS-CoV-2, and develop a mitigation plan. Several professional fertility societies have created guidelines for the best practices in patient care during the coronavirus disease 2019 pandemic. As we learn more about SARS-CoV-2, updates have been issued to help adapt infection-control and -prevention protocols. This review discusses what is currently known about SARS-CoV-2 infection risks in assisted reproductive centers and recommends the implementation of specific mitigation strategies.


Subject(s)
COVID-19/prevention & control , Health Personnel/standards , Infection Control/standards , Personal Protective Equipment/standards , Practice Guidelines as Topic/standards , Reproductive Techniques, Assisted/standards , COVID-19/epidemiology , COVID-19/transmission , Humans , Infection Control/methods , Risk Assessment/methods , Risk Assessment/standards , Severe Acute Respiratory Syndrome/epidemiology , Severe Acute Respiratory Syndrome/prevention & control , Severe Acute Respiratory Syndrome/transmission
19.
Curr Opin Pulm Med ; 27(3): 146-154, 2021 05 01.
Article in English | MEDLINE | ID: covidwho-1116526

ABSTRACT

PURPOSE OF REVIEW: Severe acute respiratory syndrome-coronaviruses-2 (SARS-CoV-2), the cause of coronavirus disease 2019 (COVID-19), emerged as a new zoonotic pathogen of humans at the end of 2019 and rapidly developed into a global pandemic. Over 106 million COVID-19 cases including 2.3 million deaths have been reported to the WHO as of February 9, 2021. This review examines the epidemiology, transmission, clinical features, and phylogenetics of three lethal zoonotic coronavirus infections of humans: SARS-CoV-1, SARS-CoV-2, and The Middle East respiratory syndrome coronavirus (MERS-COV). RECENT FINDINGS: Bats appear to be the common natural source of SARS-like CoV including SARS-CoV-1 but their role in SARS-CoV-2 and MERS-CoV remains unclear. Civet cats and dromedary camels are the intermediary animal sources for SARS-CoV-1 and MERS-CoV infection, respectively whereas that of SARS-CoV-2 remains unclear. SARS-CoV-2 viral loads peak early on days 2-4 of symptom onset and thus high transmission occurs in the community, and asymptomatic and presymptomatic transmission occurs commonly. Nosocomial outbreaks are hallmarks of SARS-CoV-1 and MERS-CoV infections whereas these are less common in COVID-19. Several COVID-19 vaccines are now available. SUMMARY: Of the three lethal zoonotic coronavirus infections of humans, SARS-CoV-2 has caused a devastating global pandemic with over a million deaths. The emergence of genetic variants, such as D614G, N501Y (variants 1 and 2), has led to an increase in transmissibility and raises concern about the possibility of re-infection and impaired vaccine response. Continued global surveillance is essential for both SARS-CoV-2 and MERS-CoV, to monitor changing epidemiology due to viral variants.


Subject(s)
COVID-19 , Communicable Disease Control , Coronavirus Infections , Severe Acute Respiratory Syndrome , Animals , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19/transmission , Chain of Infection , Chiroptera/virology , Communicable Disease Control/methods , Communicable Disease Control/organization & administration , Coronavirus Infections/epidemiology , Coronavirus Infections/prevention & control , Coronavirus Infections/transmission , Humans , Phylogeny , SARS-CoV-2/isolation & purification , SARS-CoV-2/pathogenicity , Severe Acute Respiratory Syndrome/epidemiology , Severe Acute Respiratory Syndrome/prevention & control , Severe Acute Respiratory Syndrome/transmission , Viral Zoonoses/epidemiology , Viral Zoonoses/prevention & control , Viral Zoonoses/transmission
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