Transmission — Hantavirus
Primary route: aerosolised rodent excreta
The primary mode of hantavirus transmission to humans is inhalation of aerosolised rodent urine, droppings, or saliva. When contaminated dust is disturbed — by sweeping, cleaning, or simply entering an enclosed space — viral particles become airborne and can be inhaled deep into the lungs.
Rodent reservoirs by region
Different hantavirus strains are maintained by specific rodent hosts:
| Virus strain | Primary reservoir | Region | Syndrome |
|---|---|---|---|
| Sin Nombre | Deer mouse (Peromyscus maniculatus) | North America | HPS |
| New York | White-footed mouse (P. leucopus) | Eastern North America | HPS |
| Black Creek Canal | Rice rat (Oryzomys palustris) | Southeastern US | HPS |
| Bayou | Cotton rat (Sigmodon hispidus) | Southeastern US | HPS |
| Andes | Long-tailed pygmy rice rat (Oligoryzomys longicaudatus) | Chile, Argentina | HPS |
| Laguna Negra | Small vesper mouse (Calomys laucha) | Paraguay, Bolivia | HPS |
| Hantaan | Striped field mouse (Apodemus agrarius) | China, Korea, Russia | HFRS |
| Puumala | Bank vole (Myodes glareolus) | Scandinavia, Europe | HFRS (mild) |
| Dobrava-Belgrade | Yellow-necked mouse (A. flavicollis) | Balkans, Europe | HFRS |
| Seoul | Norway rat (Rattus norvegicus) | Worldwide | HFRS |
Person-to-person transmission: Andes virus
The Andes virus is the only hantavirus for which person-to-person (human-to-human, H2H) transmission has been documented. The first well-studied H2H cluster occurred in El Bolsón, Argentina in 1996, where a patient infected 5 contacts including physicians, with a 50% case fatality rate among secondary cases.
Case study: MV Hondius cluster (May 2026)
In May 2026, a confirmed Andes-strain hantavirus outbreak aboard the MV Hondius tourist vessel in the Drake Passage demonstrated potential maritime H2H transmission. Six confirmed cases resulted in four deaths (CFR 67%). The confined ship environment and close-quarters living conditions amplified the spread. This event represents the first documented hantavirus cluster in an Antarctic-adjacent maritime setting and underscores the importance of rapid isolation and contact tracing when Andes virus is suspected.
What does NOT transmit hantavirus
- Mosquitoes and ticks — hantaviruses are not arthropod-borne
- Casual contact — touching, hugging, or being near an infected person (except Andes virus close contact)
- Household pets — dogs and cats do not carry hantavirus
- Farm animals — livestock are not reservoirs
- Water or food — ingestion is not a documented route
Sources
- WHO. Hantavirus diseases. WHO Technical Report Series, 2023. https://www.who.int/health-topics/hantavirus
- CDC. Hantavirus: Transmission. https://www.cdc.gov/hantavirus/transmission/
- Ferres M, et al. Person-to-person transmission of Andes virus. NEJM 2007; 357:398-399. DOI
- Padula PJ, et al. Genetic diversity and distribution of hantaviruses in Argentina. J Virol 2000.