Dataset Information

High prevalence of SARS-CoV-2 antibodies in care homes affected by COVID-19: Prospective cohort study, England.

ABSTRACT:

Background

We investigated six London care homes experiencing a COVID-19 outbreak and found high rates of SARS-CoV-2 infection among residents and staff. Here we report follow-up investigations including antibody testing in the same care homes five weeks later.

Methods

Residents and staff in the initial investigation had a repeat nasal swab for SARS-CoV-2 RT-PCR and a blood test for SARS CoV-2 antibodies using ELISA based on SARS-CoV-2 native viral antigens derived from infected cells and virus neutralisation.

Findings

Of the 518 residents and staff in the initial investigation, 186/241 (77.2%) surviving residents and 208/254 (81.9%) staff underwent serological testing. Almost all SARS-CoV-2 RT-PCR positive residents and staff were seropositive five weeks later, whether symptomatic (residents 35/35, 100%; staff, 22/22, 100%) or asymptomatic (residents 32/33, 97.0%; staff 21/22, 95.5%). Symptomatic but SARS-CoV-2 RT-PCR negative residents and staff also had high seropositivity rates (residents 23/27, 85.2%; staff 18/21, 85.7%), as did asymptomatic RT-PCR negative individuals (residents 61/91, 67.0%; staff 95/143, 66.4%). Neutralising antibody was detected in 118/132 (89.4%) seropositive individuals and was not associated with age or symptoms. Ten residents (10/79 re-tested, 12.7%) remained RT-PCR positive but with higher RT-PCR cycle threshold values; 7/10 had serological testing and all were seropositive. New infections were detected in three residents and one staff.

Interpretation

RT-PCR provides a point prevalence of SARS-CoV-2 infection but significantly underestimates total exposure in outbreak settings. In care homes experiencing large COVID-19 outbreaks, most residents and staff had neutralising SARS-CoV-2 antibodies, which was not associated with age or symptoms.

Funding

PHE.

SUBMITTER: Ladhani SN

PROVIDER: S-EPMC7644437 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Publications

High prevalence of SARS-CoV-2 antibodies in care homes affected by COVID-19: Prospective cohort study, England.

Ladhani Shamez N SN Jeffery-Smith Anna A Patel Monika M Janarthanan Roshni R Fok Jonathan J Crawley-Boevey Emma E Vusirikala Amoolya A Fernandez Ruiz De Olano Elena E Perez Marina Sanchez MS Tang Suzanne S Dun-Campbell Kate K Evans Edward Wynne- EW Bell Anita A Patel Bharat B Amin-Chowdhury Zahin Z Aiano Felicity F Paranthaman Karthik K Ma Thomas T Saavedra-Campos Maria M Ellis Joanna J Chand Meera M Brown Kevin K Ramsay Mary E ME Hopkins Susan S Shetty Nandini N Chow J Yimmy JY Gopal Robin R Zambon Maria M

EClinicalMedicine 20201106

<h4>Background</h4>We investigated six London care homes experiencing a COVID-19 outbreak and found high rates of SARS-CoV-2 infection among residents and staff. Here we report follow-up investigations including antibody testing in the same care homes five weeks later.<h4>Methods</h4>Residents and staff in the initial investigation had a repeat nasal swab for SARS-CoV-2 RT-PCR and a blood test for SARS CoV-2 antibodies using ELISA based on SARS-CoV-2 native viral antigens derived from infected c ...[more]

PMID: 33173854

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Dataset Information

High prevalence of SARS-CoV-2 antibodies in care homes affected by COVID-19: Prospective cohort study, England.

Background

Methods

Findings

Interpretation

Funding

Publications

High prevalence of SARS-CoV-2 antibodies in care homes affected by COVID-19: Prospective cohort study, England.

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