Factors Associated with the Clinical Outcome of Severe Acute Respiratory Syndrome Due to COVID-19 in Brazil, 2024

Severe acute respiratory syndrome (SARS), caused by the COVID-19 virus, continues to pose a significant public health challenge in Brazil, particularly in 2024, with high mortality rates among vulnerable groups. This study aimed to describe the sociodemographic, clinical and vaccination profiles of SARS cases due to COVID-19 in Brazil in 2024, as well as analysing factors associated with clinical outcomes such as death, admission to the intensive care unit (ICU) and the need for ventilatory support. A total of 30,529 reported cases were analysed. On average, the interval between the last vaccine dose and symptom onset was 30.31 months (SD = 6.77), while the interval between symptom onset and clinical outcome was 13.26 days (SD = 16.55), revealing significant variability. The results showed higher mortality rates among men (23.7%) than women (19.1%) (p < 0.0001). Mortality increased progressively with age, reaching 24.4% in individuals aged 60 years or older, whereas rates were below 2% in children under 10 years of age. The highest proportions of deaths were observed regionally in the Northeast (26.8%) and North (22.6%), in contrast to the Midwest (17.7%) (p < 0.0001). Men were also more likely to require ICU admission (38.1% vs. 33.6%) and ventilation (62.9% vs. 60.5%). A time interval of over 24 months since the last vaccine dose was associated with higher mortality (21.9% vs. 20.6%; p = 0.0005). These results highlight the importance of ongoing surveillance and updating the vaccination schedule, particularly for more vulnerable populations.