Overview
- The latest national bulletin reports 23 confirmed cases in 2025, a 17% increase over the 2020–2024 average, with nine deaths for a 39% case-fatality rate.
- Roughly 70% of infections are in the Central Region, led by Buenos Aires province and including CABA, Santa Fe and Entre Ríos, which also accounts for most deaths.
- Transmission is primarily from exposure to infected rodents or their excreta, while human-to-human spread is rare and documented only for the Patagonian Andes strain under close contact.
- Cases concentrate between September and April with peaks typically from November to January, prompting intensified surveillance and public communication ahead of high-risk months.
- With no effective antivirals, authorities urge prevention steps such as ventilating closed spaces, wet cleaning to avoid aerosolized dust, sealing rodent entry points, and seeking prompt care for compatible symptoms.