Profile of Brazilian inpatients with COVID-19 vaccine breakthrough infection and risk factors for unfavorable outcome.

Abstract

Objective. To characterize the epidemiological and clinical profile of individuals more likely to become infected with SARS-CoV-2 after the fully vaccination schedule in order to profile priority groups to receive a booster dose in situations of vaccine doses shortage as well as for maintenance of personal protective care. Methods. This cross-sectional study used data from hospitalized COVID-19 patients aged ≥18 years, who had been fully vaccinated and had a SARS-CoV-2 infection positive diagnosis collected from the SIVEP-Gripe database (Influenza Epidemiological Surveillance Information System) from January 18, 2021 to September

15, 2021. Demographic data, clinical symptoms and preexisting medical conditions (comorbidities) were ana- lyzed. The primary outcome was in-hospital death.

Results. The majority of hospitalized patients with vaccine breakthrough infection were ≥60 years old, male, with critical or severe COVID-19. The fatality rate was extremely high (50.27%) and more pronounced in elderly

groups. The most prevalent symptoms were cough, dyspnea, respiratory distress, and low blood oxygen sat- uration. The most frequent comorbidities were heart disease and diabetes. High fatality rates were observed

among patients admitted to the intensive care units (72.88%) and those who required invasive mechanical

ventilation (87.82%). The main risk factors for an unfavorable outcome were older age, respiratory compro- mise, inactivated virus vaccine immunization, and preexisting medical conditions.

Conclusions. We characterized the profile of hospitalized Brazilian patients with COVID-19 vaccine break- through infection and the risk factors for an unfavorable outcome. These data allow to identify priority groups

to receive a booster dose and to continue using personal protection.