Strain Profile

Andes virus

Of the more than two dozen hantaviruses known to cause human disease, Andes virus stands alone for one reason: it is the only one repeatedly documented to spread from person to person, including among healthcare workers and within households.

At a glance

Reservoir
Long-tailed pygmy rice rat (Oligoryzomys longicaudatus)
Geography
Argentina, Chile, and parts of Patagonia
Disease
Hantavirus Pulmonary Syndrome (HPS)
Case fatality
Approximately 30–40%
Distinguishing feature
The only hantavirus with confirmed human-to-human transmission
First identified
1995, following an outbreak in El Bolsón, Argentina

Why person-to-person spread matters

The 1996 outbreak in southern Argentina is the canonical example: investigators traced cases among physicians and family members who had no rodent exposure. Genetic sequencing confirmed identical viral strains across linked cases. Subsequent outbreaks in Chile have reinforced the pattern.

The mechanism is thought to be respiratory droplets and close contact during the early symptomatic phase. The implication for clinicians is significant: suspected Andes virus cases require contact and droplet precautions in addition to the standard rodent exposure history.

Clinical course

Andes virus produces classic HPS with a febrile prodrome followed by rapid pulmonary edema and shock. Renal involvement is more common than with North American strains. Care is supportive; ECMO has been used successfully in referral centers in Santiago and Buenos Aires.