Nationwide surveillance system to evaluate hospital-acquired COVID-19 in Brazilian hospitals

Although the risk of SARS-CoV-2 transmission within hospitals has been well recognized, there is a paucity of data on its occurrence. Our aim was to report the incidence of hospital-acquired (HA) COVID-19 at Brazilian hospitals. We investigated the incidence of HA COVID-19 in Brazilian hospitals using data from a national surveillance system, from August 2020 through September 2021. Definitions of HA COVID-19 were: (1) symptom onset >14 days after hospital admission plus a positive SARS-CoV-2 RNA or antigen test; (2) symptom onset on days 8–14 after admission, plus a positive SARS-CoV-2 RNA or antigen test positive, plus documented high-risk exposure. We performed descriptive analyses and reported HA COVID-19 rates using pooled mean and percentile distribution. A total of 48,634 cases of HA COVID-19 were reported from 1428 hospitals. Incidence ranged from 0.16/1000 patient-days at neonatal intensive care units (ICUs) to 5.8/1000 patient-days at adult ICUs. The highest incidence of HA COVID-19 was during the months March to July 2021, similar to that which was observed for community-acquired COVID-19. This report provides a national view of the burden of HA COVID-19. The highest incidence of HA COVID-19 similar that which was observed for community-acquired COVID-19. We believe that this reflects the difficulty of implementing preventive measures. Further studies evaluating risk factors for the hospital transmission of SARS-Cov-2 should clarify strategies to minimize the risk of HA COVID-19 and may be applicable to other respiratory diseases. Furthermore, the implementation of a national system to evaluate HA COVID-19 has the potential to shine a light on this problem and lead to interventions in each hospital.