Overview
- By mid-May national surveillance recorded 45 confirmed hantavirus cases in Argentina and 33 deaths, producing an unusually high case-fatality ratio for the 2025–2026 season.
- The province of Buenos Aires has been declared in outbreak with 18 confirmed cases, seven deaths and an epidemiological index of 1.67 that exceeds the 1.25 outbreak threshold.
- An international cluster tied to the cruise MV Hondius has been linked to the Andes variant, which is notable because it can transmit between people and prompted WHO-led follow-up of passengers.
- ANLIS‑Malbrán teams have set up mobile labs in Ushuaia and deployed roughly 200 rodent traps to collect samples, run on-site testing and sequence virus material to locate reservoirs and infection sites.
- Researchers in Chile report two fully human recombinant antibodies that protected hamsters in preclinical tests, but advancing to human trials is stalled by funding shortfalls estimated at several million dollars.