Distribuição e caracterização demográfica, vacinal e epidemiológica de casos de síndrome respiratória aguda grave associada à Covid-19

Abstract

Severe Acute Respiratory Infection (SARI) associated with SARS-CoV-2 infection remains an important cause of hospitalization and death in the post-emergency COVID-19 period, in a context of marked regional inequalities in Brazil. This study aimed to characterize cases and deaths from SARI associated with COVID-19 in Brazilian regions, considering demographic, clinical and vaccination aspects between 2023 and 2024. An analytical ecological study was conducted using secondary data from the national influenza surveillance information system and from COVID-19 notifications of the Ministry of Health. Incidence, mortality and lethality coefficients for SARI associated with COVID-19 were calculated, and log-binomial regression analysis was performed to estimate risk ratios for death according to sociodemographic, regional, vaccination and risk-factor variables. During the period, 428,684 SARI cases were reported, of which 59,957 (14%) were classified as SARI due to COVID-19, resulting in a national incidence of 3,575.6 cases of SARI associated with COVID-19 per 100,000 new COVID-19 cases. The highest mortality coefficients were observed in the Southeast and South regions, whereas lethality rates were higher in the Northeast and North. Among patients with SARI associated with COVID-19, mean age was 71,7-year-old among those who died, and male sex was associated with an increased risk of death. Higher education levels were associated with lower mortality, even after adjustment for sociodemographic variables, vaccination and comorbidities. It was also observed that 76.7% of cases had received COVID-19 vaccine and that vaccination was associated with an approximate 20% reduction in the risk of death, while influenza vaccination showed no statistically significant association. The findings indicate that COVID-19 continues to play a relevant role in the profile of SARI in Brazil and reinforce the need to maintain epidemiological surveillance and to implement regionally oriented vaccination and care strategies to reduce severe outcomes.