CLINICAL-EPIDEMIOLOGICAL PROFILE OF ACUTE RESPIRATORY INFECTIONS TRIGGERED BY RESPIRATORY SYNCYTIAL VIRUS (RSV) OCCURRING IN NORTHERN BRAZIL BETWEEN NOVEMBER 2024 AND MAY 2025

Respiratory syncytial virus (RSV) is a pathogen widely disseminated in the population and is one of the main causes of acute lower respiratory tract infections in infants and older adults. RSV infection has a major public health impact, contributing to increased hospitalizations during seasonal periods. This study aims to describe clinical and epidemiological aspects of acute respiratory infection (ARI) cases associated with RSV in states in the Northern Region (Acre, Amapá, and Roraima) occurring between November 2024 and May 2025. From November 2024 to May 2025, 115 RSV-positive respiratory secretion samples from the states of AC, AM, and RR were analyzed. Samples underwent real-time RT-PCR typing to identify subgroups A and B. Epidemiological data were also assessed, such as sex, age group, seasonality, and clinical outcome (hospitalized—severe acute respiratory syndrome [SARS] vs non-hospitalized—influenza-like illness [ILI]). Of the 115 samples analyzed, 103 (89.56%) were from the state of Acre. Regarding sex distribution, 58 (50.43%) cases were male and 57 (49.56%) female. The most affected age group was infants under one year of age, with 79 (68.69%) cases, reflecting their greater vulnerability to infection. Regarding clinical outcome, 96 (83.47%) patients required hospitalization, evidencing the association of RSV with severe cases, especially in infants. As for subgroup, of the 115 RSV-positive samples, 114 were submitted for typing; among these, 68 (59.65%) were classified as RSV A and 46 (40.35%) as RSV B. A higher incidence was observed between epidemiological weeks 13 and 19, corresponding to late March and early May, consistent with the seasonal pattern observed in previous years in the Northern Region. Our findings corroborate the relevance of RSV as an agent of severe respiratory infections, especially in children under one year of age, who showed the highest hospitalization rate. The predominance of subgroup A is consistent with available literature. Given the data presented, it is essential to strengthen surveillance actions focused on ARI cases triggered by RSV. These strategies are crucial to reduce disease burden, prevent hospitalizations, and minimize the impact of RSV, especially in the pediatric population.