A study of universal SARS-CoV-2 RNA testing of residents and staff in a large group of care homes in South London

Marossy, Agnes; Rakowicz, Stefan; Bhan, Angela; Noon, Sarah; Rees, Amanda; Virk, Manjinder; Nazafi, Ayazali; Hay, Evie; de Thomasson, Louise; Windle, Christina; Zuckerman, Mark

BACKGROUND: Care homes have experienced a high number of COVID-19 related deaths of residents since the onset of the pandemic. However, up to May 2020, there has been a lack of information about the extent of SARS-CoV-2 infection in residents and staff in care homes and limited testing in this setting. RESULTS: Overall, the point prevalence of SARS-CoV-2 infection was 6.5% with a higher rate in residents (9.0%) than in staff (4.7%). A key finding was the high proportion of asymptomatic infection detected in staff (69%) and residents (51%) with evidence of under-detection of symptoms by care home staff. CONCLUSIONS: The high proportion of asymptomatic infection combined with under detection of symptoms by care home staff indicates that offering a test to all residents and staff in care homes with rapid reporting of results would assist accurate identification of infected individuals, facilitating prompt infection prevention and control action. METHODS: Combined nose and throat swab testing for SARS-CoV-2 RNA was carried out in 2455 residents and staff across 37 care homes in the London Borough of Bromley across a three-week period. Results were reported within 24 hours of sample delivery and data were collected on the presence or absence of symptoms.