RSV is one of the main causes of respiratory infections in children and has been recognized as an important pathogen in older adults, leading to increased hospitalization rates among those over 65 years of age. To describe the epidemiological situation of Severe Acute Respiratory Syndrome (SARS) cases caused by RSV in the State of São Paulo (SP), Brazil, from 01/01/2025 to 06/21/2025. Ecological study using SIVEP-Gripe data through the 25th Epidemiological Week (EW) of 2025 in SP. In the period analyzed, 7,008 SARS cases due to RSV and 101 deaths were recorded, with EW 18 standing out with 635 cases. A higher proportion of cases occurred in children up to 4 years of age (93.7%), especially infants under 1 year (70.2%). Regarding deaths, there was predominance among individuals 60 years or older (52.27%), followed by infants under 1 year (31.8%). The most frequently reported signs and symptoms were cough (22.8%), respiratory distress (19.9%), fever (16.6%), and oxygen saturation <95% (15.2%). The most frequent risk conditions were cardiovascular diseases (27.4%), asthma (18.8%), and diabetes mellitus (12%). ICU was used in 28% of total cases (mean length of stay 9.4 days), of whom 80% required ventilatory support, and 25% required invasive ventilatory support. The highest incidence rates per 100,000 person-years, by Regional Health Department (RHD), were found in São José do Rio Preto (145.9) and Campinas (126.4). Regarding mortality rate (per 100,000 person-years), São José do Rio Preto (2.6) and Sorocaba (1.6) reported the highest figures. In the state of São Paulo, the RSV season ran from EW 13 to 25. It was observed that the most affected were young children and older adults. Measures such as respiratory etiquette, RSV vaccination, and timely use of monoclonal antibodies in eligible groups represent a key strategy for prevention and control of the virus, especially to protect the most vulnerable groups.
Alves et al. (Sun,) studied this question.