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1.
Ann Intern Med ; 174(2): 286-287, 2021 02.
Article in English | MEDLINE | ID: covidwho-1083219
2.
Ann Intern Med ; 174(2): 284, 2021 02.
Article in English | MEDLINE | ID: covidwho-1081919
3.
Ann Intern Med ; 174(2): 283, 2021 02.
Article in English | MEDLINE | ID: covidwho-1081909
4.
Ann Intern Med ; 174(2): 285-286, 2021 02.
Article in English | MEDLINE | ID: covidwho-1081462
5.
Ann Intern Med ; 174(2): 284-285, 2021 02.
Article in English | MEDLINE | ID: covidwho-1081122
6.
Ann Intern Med ; 174(2): 283-284, 2021 02.
Article in English | MEDLINE | ID: covidwho-1080986
7.
Ann Intern Med ; 174(2): 286, 2021 02.
Article in English | MEDLINE | ID: covidwho-1080401
8.
Infect Genet Evol ; 88: 104684, 2021 03.
Article in English | MEDLINE | ID: covidwho-1065474

ABSTRACT

We document two cases of viremic and prolonged active infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) where the viral genome was conserved for two months, but infection was with little or no symptoms. The first infection persisted for 80 days and the second for 62 days. Clearance of infection occurred 40 and 41 days, respectively, after development of detectable antibodies. Both cases were identified incidentally in an investigation of reinfection in a cohort of 133,266 laboratory-confirmed infected persons.


Subject(s)
Antibodies, Viral/blood , Genome, Viral , RNA, Viral/blood , Viremia/immunology , Adult , Asymptomatic Diseases , /virology , Enzyme-Linked Immunosorbent Assay , Female , Humans , Infectious Disease Incubation Period , Male , Reverse Transcriptase Polymerase Chain Reaction , /immunology , Time Factors , Viremia/diagnosis , Viremia/virology
10.
Viruses ; 13(1)2021 Jan 15.
Article in English | MEDLINE | ID: covidwho-1067778

ABSTRACT

Ferrets were experimentally inoculated with SARS-CoV-2 (severe acute respiratory syndrome (SARS)-related coronavirus 2) to assess infection dynamics and host response. During the resulting subclinical infection, viral RNA was monitored between 2 and 21 days post-inoculation (dpi), and reached a peak in the upper respiratory cavity between 4 and 6 dpi. Viral genomic sequence analysis in samples from three animals identified the Y453F nucleotide substitution relative to the inoculum. Viral RNA was also detected in environmental samples, specifically in swabs of ferret fur. Microscopy analysis revealed viral protein and RNA in upper respiratory tract tissues, notably in cells of the respiratory and olfactory mucosae of the nasal turbinates, including olfactory neuronal cells. Antibody responses to the spike and nucleoprotein were detected from 21 dpi, but virus-neutralizing activity was low. A second intranasal inoculation (re-exposure) of two ferrets after a 17-day interval did not produce re-initiation of viral RNA shedding, but did amplify the humoral response in one animal. Therefore, ferrets can be experimentally infected with SARS-CoV-2 to model human asymptomatic infection.


Subject(s)
Asymptomatic Diseases , Disease Models, Animal , /physiology , Animals , Antibodies, Viral/blood , Antibodies, Viral/immunology , /pathology , Female , Ferrets , Genome, Viral/genetics , Mutation , Nasal Mucosa/virology , RNA, Viral/genetics , Viral Load , Virus Shedding
13.
R I Med J (2013) ; 104(1): 55-60, 2021 Feb 01.
Article in English | MEDLINE | ID: covidwho-1055475

ABSTRACT

OBJECTIVE: To describe characteristics of children undergoing SARS-CoV-2 testing during the initial wave of infections in Rhode Island. METHODS: This is a descriptive study of 729 children tested for SARS-CoV-2 at four emergency departments April 9 to May 7, 2020 in Rhode Island. Demographic information and symptoms were cataloged for those tested. RESULTS: 81 (11%) children tested positive for SARS-CoV-2. 94% of positive children were symptomatic. 74% of positive cases had constitutional symptoms and 72% had upper respiratory symptoms. While only 34% of those tested were Hispanic, 68% of the SARS-CoV-2- positive cases occurred in Hispanic children. CONCLUSION: This study details the pediatric population's experience during the first wave of the pandemic in Rhode Island. It could inform testing allocation strategies in healthcare settings. It also highlights vulnerable populations in need of further public health support in our state.


Subject(s)
/diagnosis , Adolescent , Asymptomatic Diseases , /pathology , Child , Child, Preschool , Emergency Service, Hospital , Female , Humans , Infant , Male , Retrospective Studies , Rhode Island/epidemiology , Young Adult
14.
MMWR Morb Mortal Wkly Rep ; 70(1): 12-13, 2021 Jan 08.
Article in English | MEDLINE | ID: covidwho-1055329

ABSTRACT

On May 8, 2020, the Vermont Department of Health (VDH) issued a Health Update* recommending shortening the duration of quarantine for persons exposed to SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19). Exposed persons who were in quarantine could be tested by polymerase chain reaction (PCR) on or after quarantine day 7. Those who had remained asymptomatic throughout quarantine and who received a negative SARS-CoV-2 PCR test result on or after day 7 could end quarantine. This policy was based on a report suggesting that symptom onset occurs within this time frame in approximately three quarters of COVID-19 cases (1) and on consultation of the Vermont Health Commissioner with the U.S. Surgeon General. VDH implemented this policy to minimize restrictions on state residents, recognizing that some reduction could occur in the prevention benefit of quarantine to contain the spread of SARS-CoV-2. State-run SARS-CoV-2 testing sites were made available to increase access to no-cost testing and facilitate implementation of this policy. During August 1-December 1, among persons seeking testing at a VDH SARS-CoV-2 testing site, 36% stated that their reason for seeking testing was to end quarantine early (VDH, unpublished data, December 7, 2020), indicating that persons were aware of and following the policy and using the testing services provided. To assess the effectiveness of this policy, VDH analyzed testing data for contacts of persons with a COVID-19 diagnosis. During May 8-November 16, VDH identified 8,798 exposed contacts of COVID-19 patients; 3,983 (45%) had sought testing within 14 days of their exposure, with day 0 defined as the date of last exposure noted in the case investigation record. Among these persons, 2,200 (55%) who received testing on days 7-10 were included in this analysis; 977 (44.9%) of these contacts had a specimen collected for testing on day 7. Among these, 34 (3%) had test results that were positive, 940 (96%) had results that were negative, and three (<1%) had results that were indeterminate (Table). Among the 34 contacts who received a positive SARS-CoV-2 PCR test result on day 7 after exposure, 12 (35%) were asymptomatic. The remaining 22 contacts with positive test results were symptomatic at the time of testing; approximately one half had developed symptoms on days 4-7 after exposure. Among the 940 contacts who received negative test results on specimens collected on day 7 after exposure, 154 (16%) had a subsequent test within the next 7 days (i.e., days 8-14); among these, 152 (99%) had tests that remained negative, and two (1%) had results that were indeterminate.


Subject(s)
Asymptomatic Diseases , /prevention & control , Contact Tracing , Quarantine/statistics & numerical data , Athletes , /epidemiology , Guideline Adherence/statistics & numerical data , Guidelines as Topic , Humans , Public Policy , Time Factors , Universities , Vermont/epidemiology , Young Adult
15.
PLoS One ; 16(1): e0246084, 2021.
Article in English | MEDLINE | ID: covidwho-1050493

ABSTRACT

The Nicaraguan COVID-19 situation is exceptional for Central America. The government restricts testing and testing supplies, and the true extent of the coronavirus crisis remains unknown. Dozens of deaths have been reported among health-care workers. However, statistics on the crisis' effect on health-care workers and their risk of being infected with SARS-CoV-2 are lacking. We aimed to estimate the prevalence of SARS-CoV-2 infection in health-care workers and to examine correlations with risk factors such as age, sex and comorbidities. Study participants (N = 402, median age 38.48 years) included physicians, nurses and medical assistants, from public and private hospitals, independent of symptom presentation. SARS-CoV-2 was detected on saliva samples using the loop-mediated isothermal amplification assay. A questionnaire was employed to determine subjects' COVID-19-associated symptoms and their vulnerability to complications from risk factors such as age, sex, professional role and comorbidities. The study was performed five weeks into the exponential growth period in Nicaragua. We discovered that 30.35% of health-care workers participating in our study had been infected with SARS-CoV-2. A large percentage (54.92%) of those who tested positive were asymptomatic and were still treating patients. Nearly 50% of health-care workers who tested positive were under 40, an astonishing 30.33% reported having at least one comorbidity. In our study, sex and age are important risk factors for the probability of testing positive for SARS-CoV-2 with significance being greatest among those between 30 and 40 years of age. In general, being male resulted in higher risk. Our data are the first non-governmental data obtained in Nicaragua. They shed light on several important aspects of COVID-19 in an underdeveloped nation whose government has implemented a herd-immunity strategy, while lacking an adequate healthcare system and sufficient PPE for health-care workers. These data are important for creating policies for containing the spread of SARS-CoV-2.


Subject(s)
/epidemiology , Health Personnel/statistics & numerical data , Adult , Aged , Asymptomatic Diseases/epidemiology , Coronavirus Infections/epidemiology , Coronavirus Infections/virology , Female , Humans , Infectious Disease Transmission, Patient-to-Professional/statistics & numerical data , Male , Middle Aged , Nicaragua/epidemiology , Prevalence , Risk Factors , Saliva/virology
16.
Lung ; 199(1): 7-12, 2021 02.
Article in English | MEDLINE | ID: covidwho-1047240

ABSTRACT

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infects both children and adults but epidemiological and clinical data demonstrate that children are less likely to have a severe disease course or die. Furthermore, asthmatic children show less severe disease manifestations when infected with SARS-CoV-2 comparing to adults. This review focuses on SARS-CoV-2 and childhood asthma interaction and aims at summarizing the current knowledge of the potential mechanisms that ameliorate disease symptomatology in asthmatic children.


Subject(s)
Asthma , /pathogenicity , Age Factors , Asthma/epidemiology , Asthma/immunology , Asymptomatic Diseases , /mortality , Child , Female , Host-Pathogen Interactions , Humans , Male , Prognosis , Protective Factors , Risk Factors , Severity of Illness Index
17.
Nature ; 589(7842): 363-370, 2021 01.
Article in English | MEDLINE | ID: covidwho-1039649

ABSTRACT

There have been several major outbreaks of emerging viral diseases, including Hendra, Nipah, Marburg and Ebola virus diseases, severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS)-as well as the current pandemic of coronavirus disease 2019 (COVID-19). Notably, all of these outbreaks have been linked to suspected zoonotic transmission of bat-borne viruses. Bats-the only flying mammal-display several additional features that are unique among mammals, such as a long lifespan relative to body size, a low rate of tumorigenesis and an exceptional ability to host viruses without presenting clinical disease. Here we discuss the mechanisms that underpin the host defence system and immune tolerance of bats, and their ramifications for human health and disease. Recent studies suggest that 64 million years of adaptive evolution have shaped the host defence system of bats to balance defence and tolerance, which has resulted in a unique ability to act as an ideal reservoir host for viruses. Lessons from the effective host defence of bats would help us to better understand viral evolution and to better predict, prevent and control future viral spillovers. Studying the mechanisms of immune tolerance in bats could lead to new approaches to improving human health. We strongly believe that it is time to focus on bats in research for the benefit of both bats and humankind.


Subject(s)
Chiroptera/immunology , Chiroptera/virology , Disease Reservoirs/veterinary , /transmission , Animals , Asymptomatic Diseases , Disease Reservoirs/virology , Evolution, Molecular , Humans , Immune Tolerance , /virology
18.
Nat Commun ; 12(1): 333, 2021 01 12.
Article in English | MEDLINE | ID: covidwho-1026820

ABSTRACT

COVID-19 is affecting healthcare resources worldwide, with lower and middle-income countries being particularly disadvantaged to mitigate the challenges imposed by the disease, including the availability of a sufficient number of infirmary/ICU hospital beds, ventilators, and medical supplies. Here, we use mathematical modelling to study the dynamics of COVID-19 in Bahia, a state in northeastern Brazil, considering the influences of asymptomatic/non-detected cases, hospitalizations, and mortality. The impacts of policies on the transmission rate were also examined. Our results underscore the difficulties in maintaining a fully operational health infrastructure amidst the pandemic. Lowering the transmission rate is paramount to this objective, but current local efforts, leading to a 36% decrease, remain insufficient to prevent systemic collapse at peak demand, which could be accomplished using periodic interventions. Non-detected cases contribute to a ∽55% increase in R0. Finally, we discuss our results in light of epidemiological data that became available after the initial analyses.


Subject(s)
/epidemiology , Models, Theoretical , Pandemics , Asymptomatic Diseases , Brazil/epidemiology , /transmission , Epidemiologic Methods , Hospitalization/statistics & numerical data , Humans , Intensive Care Units
19.
Vaccine ; 39(4): 667-677, 2021 01 22.
Article in English | MEDLINE | ID: covidwho-1023764

ABSTRACT

INTRODUCTION: Emerging evidence suggests young children are at greater risk of COVID-19 infection than initially predicted. However, a comprehensive understanding of epidemiology of COVID-19 infection in young children under five years, the most at-risk age-group for respiratory infections, remain unclear. We conducted a systematic review and meta-analysis of epidemiological and clinical characteristics of COVID-19 infection in children under five years. METHOD: Following the Preferred Reporting Items for Systematic Reviews and Meta-analyses , we searched several electronic databases (Pubmed, EMBASE, Web of Science, and Scopus) with no language restriction for published epidemiological studies and case-reports reporting laboratory-confirmed COVID-19 infection in children under five years until June 4, 2020. We assessed pooled prevalence for key demographics and clinical characteristics using Freeman-Tukey double arcsine random-effects model for studies except case-reports. We evaluated risk of bias separately for case-reports and other studies. RESULTS: We identified 1,964 articles, of which, 65 articles were eligible for systematic review that represented 1,214 children younger than five years with laboratory-confirmed COVID-19 infection. The pooled estimates showed that 50% young COVID-19 cases were infants (95% CI: 36% - 63%, 27 studies); 53% were male (95% CI: 41% - 65%, 24 studies); 43% were asymptomatic (95% CI: 15% - 73%, 9 studies) and 7% (95% CI: 0% - 30%, 5 studies) had severe disease that required intensive-care-unit admission. Of 139 newborns from COVID-19 infected mothers, five (3.6%) were COVID-19 positive. There was only one death recorded. DISCUSSION: This systematic review reports the largest number of children younger than five years with COVID-19 infection till date. Our meta-analysis shows nearly half of young COVID-19 cases were asymptomatic and half were infants, highlighting the need for ongoing surveillance to better understand the epidemiology, clinical pattern, and transmission of COVID-19 to develop effective preventive strategies against COVID-19 disease in young paediatric population.


Subject(s)
/epidemiology , Infectious Disease Transmission, Vertical/statistics & numerical data , /pathogenicity , Adult , Asymptomatic Diseases , /virology , Child, Preschool , Epidemiological Monitoring , Female , Humans , Incidence , Infant , Infant, Newborn , Intensive Care Units , Male , Mothers , Publication Bias/statistics & numerical data , Severity of Illness Index
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