Oropouche fever in Minas Gerais, Brazil, 2024: Epidemiological characterization, spatial distribution, and clinical implications.

Abstract

Background: Oropouche fever (OF), caused by the Oropouche virus (OROV), has historically been endemic to the Amazon region; however, it is now emerging in other Brazilian states. This study describes the sociodemographic, clinical, and spatial characteristics of OROV cases identified in Minas Gerais in 2024 and contributes to the understanding of its transmission dynamics in non-endemic regions.

Methods: This descriptive epidemiological study used the official surveillance data from the State Health Department of Minas Gerais (SES/MG). The confirmed cases were those with laboratory-confirmed OROV infection by RT-PCR at the Ezequiel Dias Foundation (FUNED). Demographic, geographic, and clinical data were analyzed using descriptive statistics. Exploratory comparisons by sex and age were performed.

Results: A total of 278 confirmed autochthonous cases were reported across 10 municipalities, primarily in rural and peri-urban areas. Women accounted for 55.0% of the cases, with the highest incidence among adults aged 20-59 years. Two temporal peaks were observed at epidemiological weeks 15 and 50, corresponding to distinct clusters in Joanésia and Piau, respectively. Symptom recurrence occurred in 25.5% of the cases. Headache, myalgia, gastrointestinal symptoms, dysgeusia, pruritus, and skin lesions were more common in women than in men. Hypertension and diabetes mellitus were the most common comorbidities. More than half the participants reported the presence of domestic animals nearby.

Conclusions: This study confirmed the geographic expansion of OROV in southeastern Brazil and identified distinct temporal and spatial transmission patterns. These findings underscore the importance of strengthened arbovirus surveillance, improved laboratory capacity, and integrated vector control strategies.