Participants
As previously reported 16,19,20, as soon as a resident developed COVID-19 in a NH, all residents and staff members were repeatedly tested using RT-PCR on nasopharyngeal swabs until no new cases were diagnosed. This was the procedure recommended by the Health Agency of our region, in accordance with the European Geriatric Medicine Society guidance 3.
All residents who had not had COVID-19 in the last 3 months, and who signed an informed consent, were offered a first jab of the BNT162b2 vaccine between January and March 2021. According to the national recommendations in NHs, a second jab, irrespective of prior COVID-19 history, was offered three weeks later. Residents and their family, relatives or legal representative were informed of the possibility to measure the antibody response after the first and second jabs and of the fact that the residents’ anonymised clinical and biological data would be used for research purposes. The study was approved by the Montpellier University Hospital institutional review board (IRB-MTP_2020_06_202000534 and IRB-MTP _2021_04_202000534).