Analysis of 472,688 severe cases of COVID-19 in Brazil showed lower mortality in those vaccinated against influenza

Objective: To analyze the severe cases of COVID-19 in Brazil in 2020 and compare those vaccinated and unvaccinated against influenza in invasive ventilation, admission in Intensive Care Unit (ICU), and deaths. Method: Cross-sectional study with public data from the OpenDataSUS platform confirmed severe cases for COVID-19 in Brazil in the year 2020. Data were analyzed by SPSS, from the chi-square test of independence and binary logistic regression. Results: The population was 472,688 cases and 177,640 deaths, with lethality of 37.58% in severe cases. The test of independence was highly significant in vaccinated survivors (<0.0001), and regression showed an almost twofold odds ratio for invasive ventilation, ICU admission, and death in unvaccinated cases. Conclusion: We recommend mass influenza vaccination as an adjuvant in combating the COVID-19 pandemic in Brazil.