Background: COVID-19 has presented itself as one of the most important health concerns of 2020. The geriatric population is arguably hit the hardest by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The ”Prior Infection with SARS-COV-2” (PICOV) study investigates both residents and staff members from nursing homes. The primary aim of the study is to compare the time to occurrence of an influenza-like illness (ILI) or acute respiratory infection (ARI) between participants with a confirmed past SARS-CoV-2 infection and those without an infection. This paper details the study design, sampling scheme, biological measurements, and population characteristics at baseline.
Methods: In 26 Belgian nursing homes, all eligible residents and staff members with or without a past SARS-CoV-2 infection (ratio 40/60) were invited to participate. Consent was obtained from 1,375 participants and 1,226 completed the baseline questionnaire. Prevalence of symptoms during a prior SARS-CoV-2 infection was compared between residents and staff members with χ2 statistics.
Results: Nursing home residents (both with and without a prior SARS-CoV-2 infection) systematically reported fewer symptoms than staff members. Moreover, results from prior nasopharyngeal RT-qPCR and baseline serology show that antibody development after a SARS-CoV-2 infection differs between residents and staff members.
Conclusions: We can postulate that disease development and symptoms is different between a geriatric and younger population. Therefore, the occurrence and severity of a future ILI and/or ARI might vary from resident to staff.