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1.
Clin Infect Dis ; 2022 Aug 27.
Article in English | MEDLINE | ID: covidwho-2232689

ABSTRACT

We screened 65 longitudinally-collected nasal swab samples from 31 children aged 0-16 years who were positive for SARS-CoV-2 omicron BA.1. By day 7 after onset of symptoms 48% of children remained positive by rapid antigen test. In a sample subset we found 100% correlation between antigen test results and virus culture.

2.
PLoS One ; 17(8): e0273482, 2022.
Article in English | MEDLINE | ID: covidwho-2021921

ABSTRACT

Few data are available on frequency of SARS-CoV-2 infection among very young children in low- to middle-income countries (LMIC), with the studies that are available biased towards higher income countries with low reported infection and seroconversion rates. Between February 2019 and March 2021, 388 dried blood spot (DBS) samples were obtained from 257 children less than 30 months of age as part of a prospective observational cohort study of pregnant women and their infants in Haiti; longitudinal samples were available for 107 children. In a subsequent retrospective analysis, DBS samples were tested by ELISA for antibody targeting the receptor binding domain of the SARS-CoV-2 S1 protein. Over the course of the study, 16·7% of the infants became seropositive. All seropositive samples were collected after March 19, 2020 (the date of the first reported COVID-19 case in Haiti) with the highest hazards measured in August 2020. Sampling date was the only covariate associated with the hazard of seroconversion. Our data provide an estimate of SARS-CoV-2 infection rates among very young children without prior SARS-CoV-2 exposure during the initial pandemic waves in Haiti, and demonstrate that these children mount a detectable serological response which is independent of patient age.


Subject(s)
COVID-19 , Antibodies, Viral , COVID-19/epidemiology , Child , Child, Preschool , Cohort Studies , Female , Haiti/epidemiology , Humans , Immunoglobulin G , Infant , Pregnancy , Prospective Studies , Retrospective Studies , SARS-CoV-2
4.
Clin Infect Dis ; 74(11): 2057-2060, 2022 06 10.
Article in English | MEDLINE | ID: covidwho-1700565

ABSTRACT

After an initial wave of coronavirus disease 2019 (COVID-19) in Haiti in summer 2020 (primarily lineage B.1), seropositivity for anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin G (IgG) was ~40%. Variant P.1 (gamma) was introduced in February 2021, with an initially limited introduction followed by exponential local dissemination within this unvaccinated population with prior exposure to earlier SARS-CoV-2 lineages.


Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19 Testing , Haiti/epidemiology , Humans , SARS-CoV-2/genetics
5.
Nature ; 600(7887): 133-137, 2021 12.
Article in English | MEDLINE | ID: covidwho-1521757

ABSTRACT

Coronaviruses have caused three major epidemics since 2003, including the ongoing SARS-CoV-2 pandemic. In each case, the emergence of coronavirus in our species has been associated with zoonotic transmissions from animal reservoirs1,2, underscoring how prone such pathogens are to spill over and adapt to new species. Among the four recognized genera of the family Coronaviridae, human infections reported so far have been limited to alphacoronaviruses and betacoronaviruses3-5. Here we identify porcine deltacoronavirus strains in plasma samples of three Haitian children with acute undifferentiated febrile illness. Genomic and evolutionary analyses reveal that human infections were the result of at least two independent zoonoses of distinct viral lineages that acquired the same mutational signature in the genes encoding Nsp15 and the spike glycoprotein. In particular, structural analysis predicts that one of the changes in the spike S1 subunit, which contains the receptor-binding domain, may affect the flexibility of the protein and its binding to the host cell receptor. Our findings highlight the potential for evolutionary change and adaptation leading to human infections by coronaviruses outside of the previously recognized human-associated coronavirus groups, particularly in settings where there may be close human-animal contact.


Subject(s)
Coronavirus Infections/epidemiology , Coronavirus Infections/virology , Deltacoronavirus/isolation & purification , Swine/virology , Viral Zoonoses/epidemiology , Viral Zoonoses/virology , Amino Acid Sequence , Animals , Bayes Theorem , Child , Chlorocebus aethiops , Conserved Sequence , Coronavirus Infections/blood , Deltacoronavirus/classification , Deltacoronavirus/genetics , Deltacoronavirus/pathogenicity , Female , Haiti/epidemiology , Humans , Male , Models, Molecular , Mutation , Phylogeny , Vero Cells , Viral Zoonoses/blood
6.
Clin Infect Dis ; 75(1): e1184-e1187, 2022 Aug 24.
Article in English | MEDLINE | ID: covidwho-1493772

ABSTRACT

We isolated a novel coronavirus from a medical team member presenting with fever and malaise after travel to Haiti. The virus showed 99.4% similarity with a recombinant canine coronavirus recently identified in a pneumonia patient in Malaysia, suggesting that infection with this virus and/or recombinant variants occurs in multiple locations.


Subject(s)
COVID-19 , Coronavirus, Canine , Animals , Dogs , Haiti , Humans , SARS-CoV-2/genetics , Travel
7.
Endosc Int Open ; 9(8): E1276-E1282, 2021 Aug.
Article in English | MEDLINE | ID: covidwho-1376222

ABSTRACT

Background and study aims The clinical significance of SARS-CoV-2 RNA in the stool remains unclear. We aimed to determine whether SARS-CoV-2 is detected via real-time reverse transcriptase polymerase chain reaction (rRT-PCR) in the gastrointestinal tracts of patients scheduled for endoscopy and if the virus obtained from these clinical specimens could be isolated in culture. Patients and methods All patients underwent symptom screening and had negative nasopharyngeal testing for SARS-CoV-2 within 72 hours of their scheduled procedure. Study samples were collected via nasopharyngeal swab, rectal swab, and fluid from the upper gastrointestinal tract and/or colon based on their endoscopic procedure(s). Samples were tested for SARS-CoV-2 via rRT-PCR. SARS-CoV-2 positive specimens were isolated and cultured in Vero-E6 cells. Results 243 patients (mean age 63.1 years;54.3 % men) were enrolled from July 15, 2020 to September 2, 2020. SARS-CoV-2 testing was performed from 242 (99.6 %) nasopharyngeal, 243 (100 %) rectal, 183 (75.3 %) upper gastrointestinal tract and 73 (30 %) colon samples. SARS-CoV-2 RNA was detected in the nasopharynx and gastrointestinal specimens in one patient (0.4 %). After a 14-day incubation period, there was no evidence of virus growth in cells incubated with any of these specimens. Conclusions SARS-CoV-2 was rarely detected in the gastrointestinal tract of patients with negative nasopharyngeal testing prior to endoscopy. No live virus was detected by culture, further highlighting that presence of viral genome on its own is not sufficient proof of infectivity. PCR-based screening provides limited insight into virus infectivity and its results should be interpreted carefully as to avoid unnecessary delays in clinical care or inadvertent risk exposure.

8.
Int J Infect Dis ; 108: 212-216, 2021 Jul.
Article in English | MEDLINE | ID: covidwho-1364082

ABSTRACT

OBJECTIVE: To determine if viable virus could be isolated from the air within a car driven by a patient infected with SARS-CoV-2, and to assess the size range of the infectious particles. METHODS: We used a Sioutas personal cascade impactor sampler (PCIS) to screen for SARS-CoV-2 in a car driven by a COVID-19 patient. The patient, who had only mild illness without fever or cough and was not wearing a mask, drove the car for 15 min with the air conditioning turned on and windows closed. The PCIS was clipped to the sun-visor above the front passenger seat and was retrieved from the car two hours after completion of the drive. RESULTS: SARS-CoV-2 was detectable at all PCIS stages by PCR and was cultured from the section of the sampler collecting particles in the 0.25-0.50 µm size range. CONCLUSIONS: Our data highlight the potential risk of SARS-CoV-2 transmission by minimally symptomatic persons in the closed space inside of a car and suggest that a substantial component of that risk is via aerosolized virus.


Subject(s)
COVID-19 , SARS-CoV-2 , Aerosols , Automobiles , Cough , Humans
11.
Microbiol Resour Announc ; 10(8)2021 Feb 25.
Article in English | MEDLINE | ID: covidwho-1105406

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain UF-8, with an in-frame 12-nucleotide deletion within open reading frame 3a (ORF3a), was isolated from a 78-year-old COVID-19 patient in March 2020.

12.
PLoS One ; 16(1): e0245352, 2021.
Article in English | MEDLINE | ID: covidwho-1029173

ABSTRACT

In February and March, 2020, environmental surface swab samples were collected from the handle of the main entry door of a major university building in Florida, as part of a pilot surveillance project screening for influenza. Samples were taken at the end of regular classroom hours, between the dates of February 1-5 and February 19-March 4, 2020. Influenza A(H1N1)pdm09 virus was isolated from the door handle on four of the 19 days sampled. Both SARS-CoV-2 and A(H1N1)pdm09 virus were detected in a sample collected on February 21, 2020. Based on sequence analysis, the Florida SARS-CoV-2 strain (designated UF-11) was identical to strains being identified in Washington state during the same time period, while the earliest similar sequences were sampled in China/Hubei between Dec 30th 2019 and Jan 5th 2020. The first human case of COVID-19 was not officially reported in Florida until March 1st. In an analysis of sequences from COVID-19 patients in this region of Florida, there was only limited evidence of subsequent dissemination of the UF-11 strain. Identical or highly similar strains, possibly related through a common transmission chain, were detected with increasing frequency in Washington state between end of February and beginning of March. Our data provide further documentation of the rapid early spread of SARS-CoV-2 and underscore the likelihood that closely related strains were cryptically circulating in multiple U.S. communities before the first "official" cases were recognized.


Subject(s)
Environmental Monitoring , Influenza A Virus, H1N1 Subtype/isolation & purification , SARS-CoV-2/isolation & purification , Universities/statistics & numerical data , Florida , Humans , Phylogeny , SARS-CoV-2/classification , Surface Properties , Time Factors
13.
Aerosol Air Qual Res ; 20(6): 1167-1171, 2020 Jun.
Article in English | MEDLINE | ID: covidwho-1022116

ABSTRACT

The progression of COVID-19 worldwide can be tracked by identifying mutations within the genomic sequence of SARS-CoV-2 that occur as a function of time. Such efforts currently rely on sequencing the genome of SARS-CoV-2 in patient specimens (direct sequencing) or of virus isolated from patient specimens in cell cultures. A pilot SARS-CoV-2 air sampling study conducted at a clinic within a university student health care center detected the virus vRNA, with an estimated concentration of 0.87 virus genomes L-1 air. To determine whether the virus detected was viable ('live'), attempts were made to isolate the virus in cell cultures. Virus-induced cytopathic effects (CPE) were observed within two days post-inoculation of Vero E6 cells with collection media from air samples; however, rtRT-PCR tests for SARS-CoV-2 vRNA from cell culture were negative. Instead, three other fast-growing human respiratory viruses were isolated and subsequently identified, illustrating the challenge in isolating SARS-CoV-2 when multiple viruses are present in a test sample. The complete SAR-CoV-2 genomic sequence was nevertheless determined by Sanger sequencing and most closely resembles SARS-CoV-2 genomes previously described in Georgia, USA. Results of this study illustrate the feasibility of tracking progression of the COVID-19 pandemic using environmental aerosol samples instead of human specimens. Collection of a positive sample from a distance more than 2 m away from the nearest patient traffic implies the virus was in an aerosol.

14.
Int J Infect Dis ; 100: 476-482, 2020 Nov.
Article in English | MEDLINE | ID: covidwho-959836

ABSTRACT

OBJECTIVES: Because the detection of SARS-CoV-2 RNA in aerosols but failure to isolate viable (infectious) virus are commonly reported, there is substantial controversy whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can be transmitted through aerosols. This conundrum occurs because common air samplers can inactivate virions through their harsh collection processes. We sought to resolve the question whether viable SARS-CoV-2 can occur in aerosols using VIVAS air samplers that operate on a gentle water vapor condensation principle. METHODS: Air samples collected in the hospital room of two coronavirus disease-2019 (COVID-19) patients, one ready for discharge and the other newly admitted, were subjected to RT-qPCR and virus culture. The genomes of the SARS-CoV-2 collected from the air and isolated in cell culture were sequenced. RESULTS: Viable SARS-CoV-2 was isolated from air samples collected 2 to 4.8 m away from the patients. The genome sequence of the SARS-CoV-2 strain isolated from the material collected by the air samplers was identical to that isolated from the newly admitted patient. Estimates of viable viral concentrations ranged from 6 to 74 TCID50 units/L of air. CONCLUSIONS: Patients with respiratory manifestations of COVID-19 produce aerosols in the absence of aerosol-generating procedures that contain viable SARS-CoV-2, and these aerosols may serve as a source of transmission of the virus.


Subject(s)
Air Microbiology , Betacoronavirus/isolation & purification , Coronavirus Infections/virology , Pneumonia, Viral/virology , Aerosols , COVID-19 , Coronavirus Infections/transmission , Hospitals , Humans , Pandemics , Pneumonia, Viral/transmission , SARS-CoV-2
15.
medRxiv ; 2020 Aug 04.
Article in English | MEDLINE | ID: covidwho-721072

ABSTRACT

Background - There currently is substantial controversy about the role played by SARS-CoV-2 in aerosols in disease transmission, due in part to detections of viral RNA but failures to isolate viable virus from clinically generated aerosols. Methods - Air samples were collected in the room of two COVID-19 patients, one of whom had an active respiratory infection with a nasopharyngeal (NP) swab positive for SARS-CoV-2 by RT-qPCR. By using VIVAS air samplers that operate on a gentle water-vapor condensation principle, material was collected from room air and subjected to RT-qPCR and virus culture. The genomes of the SARS-CoV-2 collected from the air and of virus isolated in cell culture from air sampling and from a NP swab from a newly admitted patient in the room were sequenced. Findings - Viable virus was isolated from air samples collected 2 to 4.8m away from the patients. The genome sequence of the SARS-CoV-2 strain isolated from the material collected by the air samplers was identical to that isolated from the NP swab from the patient with an active infection. Estimates of viable viral concentrations ranged from 6 to 74 TCID50 units/L of air. Interpretation - Patients with respiratory manifestations of COVID-19 produce aerosols in the absence of aerosol-generating procedures that contain viable SARS-CoV-2, and these aerosols may serve as a source of transmission of the virus.

16.
Aerosol and Air Quality Research ; 20(6):1167-1171, 2020.
Article | WHO COVID | ID: covidwho-601949

ABSTRACT

The progression of COVID-19 worldwide can be tracked by identifying mutations within the genomic sequence of SARS-CoV-2 that occur as a function of time. Such efforts currently rely on sequencing the genome of SARS-CoV-2 in patient specimens (direct sequencing) or of virus isolated from patient specimens in cell cultures. A pilot SARS-CoV-2 air sampling study conducted at a clinic within a university student health care center detected the virus vRNA, with an estimated concentration of 0.87 virus genomes L-1 air. To determine whether the virus detected was viable ('live'), attempts were made to isolate the virus in cell cultures. Virus-induced cytopathic effects (CPE) were observed within two days post-inoculation of Vero E6 cells with collection media from air samples;however, rtRT-PCR tests for SARS-CoV-2 vRNA from cell culture were negative. Instead, three other fast-growing human respiratory viruses were isolated and subsequently identified. illustrating the challenge in isolating SARS-CoV-2 when multiple viruses are present in a test sample. The complete SAR-CoV-2 genomic sequence was nevertheless determined by Sanger sequencing and most closely resembles SARS-CoV-2 genomes previously described in Georgia, USA. Results of this study illustrate the feasibility of tracking progression of the COVID-19 pandemic using environmental aerosol samples instead of human specimens. Collection of a positive sample from a distance more than 2 m away from the nearest patient traffic implies the virus was in an aerosol.

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