Andes Virus: Person-to-Person Spread, Symptoms & Reservoir

Andes virus can cause HPS, a severe respiratory disease. Its unusual feature is documented limited spread between people after close contact with a symptomatic person.

That difference changes public-health operations: contact tracing, isolation, and monitoring are more important than they would be for most hantaviruses.

The primary natural reservoir of Andes virus is the long-tailed pygmy rice rat (Oligoryzomys longicaudatus), a wild rodent of southern South America — chiefly Argentina and Chile. People are usually infected by inhaling virus from infected rodent urine, droppings, or saliva.

This differs from North American hantavirus, where the deer mouse (Peromyscus maniculatus) carries Sin Nombre virus. UKHSA has noted that the South American rodents linked to Andes virus are not found in the UK, which is part of why the general-population risk outside the cluster is low.

Andes virus and Sin Nombre virus both cause hantavirus pulmonary syndrome (HPS), but they differ in important ways.

The person-to-person row is the key distinction: Andes virus is the only hantavirus with documented human-to-human transmission, which is why the MV Hondius cluster is monitored so closely.

WHO reported that confirmed MV Hondius cases were identified as Andes virus. The tracker currently records 11 confirmed cases, 2 probable cases, 0 inconclusive case, and 3 deaths.

Because symptoms can appear up to 42 days after exposure, contacts are monitored through 2026-06-21 in this dataset.

CDC lists signs and symptoms of HPS due to Andes virus as appearing 4 to 42 days after exposure. That is why MV Hondius contacts can remain under monitoring even when they feel well at first.

If symptoms appear during that window, the practical next step is not to use this page for self-triage. Contact the clinician or public-health authority managing the exposure.