[Evolution of COVID-19 at nursing homes from the second wave to vaccination. Description of a coordination program...

Nursing homes have suffered in a particularly pronounced way from the effects of COVID-19 so it is very convenient to know the evolution in them of the disease and the impact of SARS-CoV2 vaccination The objective of this study was to analyze COVID-19 pandemic evolution from the start of the second wave to the end of the vaccination campaign at the nursing homes. A coordination program between Primary Care and Geriatrics and Public Health services was activated.

2,668 seniors were followed at 39 nursing homes. Data from new cases, active cases, mortality and place of treatment of COVID-19 were collected. A descriptive analysis was performed with the measurement of the absolute number of positive SARS-CoV-2 cases and the frequency distribution.

Between August 7^th 2020 and February 26^th 2021, 30 outbreaks occurred at 21 nursing homes. 300 people tested positive for SARS-CoV-2 (11% of total residents). The daily average of active cases was 27,166 were hospitalized (55%). 66 patients died (22% of those infected), 54 of them (78%) at the hospital. 1,984 PCR tests were performed. The temporary profile of new cases did not follow a distribution "in waves" as in the community. Thirty-seven days after the start of the second dose of vaccination, there were no active cases until March 1^st, when new cases were under study for possible vaccine leakage.

The incidence of COVID-19 at nursing homes after the first wave of the pandemic has apparently been lower. The transmission in these centers has followed a different distribution than at community. Mass vaccination has achieved the practical disappearance of the disease.