Seroprevalence of SARS-CoV-2 infection among residents and workers of long-term care facilities in Ribeirão Preto, Brazil: an epidemiological survey

OBJECTIVE: Residents and workers in long-term care facilities (LTCF) for older adults share the same space, and residents are more susceptible to COVID-19 complications. The aim of this study was to determine the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies as an indication of previous infection of both residents and workers in LTCFs, as well as associated factors. METHODS: This epidemiological survey was conducted in Ribeirão Preto, Brazil, a medium-sized city. Stratified sampling was performed, with data collected on demographics, health, LTCF protective measures, activities of daily living, and cognition. A serological test was carried out on all selected individuals. RESULTS: The mean resident and worker ages were 80.62 (SD, 9.66) and 37.41 (SD, 12.42) years, respectively. The serological test was positive in 13.33% of the residents, who had 2.91 (SD, 1.28) chronic diseases and used 5.65 (SD, 2.79) medications. Dementia screening was negative in only 11.1%, and only 20% were independent in activities of daily living. The serological test results were positive in 25.93% of the workers, although SARS-CoV-2 had been previously detected in only 6.9%. The LTCF did not perform systematic screening of worker respiratory symptoms. CONCLUSIONS: There was a higher seroprevalence of SARS-CoV-2 among LTCF workers than residents. Systematic screening of worker symptoms before each shift was not regularly performed. The high prevalence of cognitive changes among LTCF residents can impede adherence to personal protection measures.