Is hantavirus contagious?

Most hantaviruses are not contagious between people. Transmission is overwhelmingly zoonotic — humans become infected by inhaling aerosolised rodent urine, droppings or saliva, by direct contact with rodent excreta, or rarely through a rodent bite.

The single well-documented exception is Andes virus (ANDV) in southern South America. Person-to-person transmission of ANDV has been confirmed in Argentina and Chile through household, sexual, and healthcare contact, and a recent cluster aboard the MV Hondius cruise ship is consistent with shipborne human-to-human spread. Estimated secondary attack rates among close contacts are on the order of 1–2%.

For all other species — Sin Nombre, Hantaan, Puumala, Seoul, Dobrava, Choclo, Laguna Negra — there is no convincing evidence of human-to-human transmission. Standard precautions are sufficient for healthcare workers caring for non-ANDV hantavirus patients; suspected ANDV cases should be isolated with droplet and contact precautions until ruled out (CDC/PAHO guidance).

If you have been in close indoor contact with someone diagnosed with ANDV, contact your local public-health authority — not because of high risk, but because monitoring is straightforward and effective.