ArticleThe Lancet regional health. Europe2021
Infection and transmission of SARS-CoV-2 in London care homes reporting no cases or outbreaks of COVID-19: Prospective observational cohort study, England 2020.
Article in The Lancet regional health. Europe, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 22 papers, 2 of them syntheses that pooled it.
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Who cites it
22 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Occurrence and transmission potential of asymptomatic and presymptomatic SARS-CoV-2 infections: Update of a living systematic review and meta-analysis.PLoS medicine · 2022Pooled it
- Transmission of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) from pre and asymptomatic infected individuals: a systematic review.Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases · 2022Pooled it
- Mass testing for discovery and control of COVID-19 outbreaks in adult social care: an observational study and cost-effectiveness analysis of 14 805 care homes in England.BMJ public health · 2025Article
- The potential of genomic epidemiology: capitalizing on its practical use for impact in the healthcare setting.Frontiers in public health · 2025Article
- Investigation of hospital discharge cases and SARS-CoV-2 introduction into Lothian care homes.The Journal of hospital infection · 2023Article
- SARS-CoV-2 in Nursing Homes: Analysis of Routine Surveillance Data in Four European Countries.Aging and disease · 2023Article
- Protection from infection and reinfection due to the Omicron BA.1 variant in care homes.Frontiers in immunology · 2023Article
- Evaluating the impact of testing strategies for the detection of nosocomial COVID-19 in English hospitals through data-driven modeling.Frontiers in medicine · 2023Article
- Article
- COVID-19 in French nursing homes during the second pandemic wave: a mixed-methods cross-sectional study.BMJ open · 2022Article
- Associations of air pollution with COVID-19 positivity, hospitalisations, and mortality: Observational evidence from UK Biobank.Environmental pollution (Barking, Essex : 1987) · 2022Article
- Mapping of SARS-CoV-2 IgM and IgG in gingival crevicular fluid: Antibody dynamics and linkage to severity of COVID-19 in hospital inpatients.The Journal of infection · 2022Article
- Guilt, tears and burnout-Impact of UK care home restrictions on the mental well-being of staff, families and residents.Journal of advanced nursing · 2022Article
- Serological profile of first SARS-CoV-2 reinfection cases detected within the SIREN study.The Journal of infection · 2022Article
- SARS-CoV-2-specific memory B cells can persist in the elderly who have lost detectable neutralizing antibodies.The Journal of clinical investigation · 2022Article
- Reinfection with new variants of SARS-CoV-2 after natural infection: a prospective observational cohort in 13 care homes in England.The lancet. Healthy longevity · 2021Observational
- Antibody persistence and neutralising activity in primary school students and staff: Prospective active surveillance, June to December 2020, England.EClinicalMedicine · 2021Article
- Seroprevalence of SARS-CoV-2 antibodies in university students: Cross-sectional study, December 2020, England.The Journal of infection · 2021Article
- Seroprevalence of SARS-CoV-2 among Blood Donors and Changes after Introduction of Public Health and Social Measures, London, UK.Emerging infectious diseases · 2021Article
- The challenge of asymptomatic SARS-CoV-2 transmission in care homes.The Lancet regional health. Europe · 2021Article
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Authors and funding
29 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundCare homes have been disproportionately affected by the COVID-19 pandemic. We investigated the potential role of asymptomatic infection and silent transmission in London care homes that reported no cases of COVID-19 during the first wave of the pandemic.
methodsFive care homes with no cases and two care homes reporting a single case of COVID-19 (non-outbreak homes) were investigated with nasal swabbing for SARS-CoV-2 RT-PCR and serology for SARS-CoV-2 antibodies five weeks later. Whole genome sequencing (WGS) was performed on RT-PCR positive samples. Serology results were compared with those of six care homes with recognised outbreaks.
findingsAcross seven non-outbreak homes, 718 (387 staff, 331 residents) individuals had a nasal swab and 651 (386 staff, 265 residents) had follow-up serology. Sixteen individuals (13 residents, 3 staff) in five care homes with no reported cases were RT-PCR positive (care home positivity rates, 0 to 7.6%) compared to 13 individuals (3.0 and 10.8% positivity) in two homes reporting a single case.Seropositivity across these seven homes varied between 10.7-56.5%, with four exceeding community seroprevalence in London (14.8%). Seropositivity rates for staff and residents correlated significantly (r
interpretationWe found high rates of asymptomatic infection and transmission even in care homes with no COVID-19 cases. The higher seropositivity rates compared to RT-PCR positivity highlights the true extent of the silent outbreak.
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