How Does It Spread?

A man goes to a birthday party, sits next to someone with hantavirus, catches it, gives it to his wife, and dies. His wife then infects 10 more people at his wake. Another guest at that same birthday party has no interaction with the index patient except to say “hello” as they cross paths, but that person gets sick too.One index patient, 33 subsequent infections, 11 deaths, four waves of transmission.This is from a meticulously documented hantavirus outbreak in Argentina in late 2018 and early 2019, published in the New England Journal of Medicine (NEJM). Nearly the exact same Andes strain of hantavirus caused the recent outbreak on the Dutch cruise ship MV Hondius. Yet from the moment this latest outbreak hit the news last month, public-health officials have been claiming that this virus is spread through “prolonged close contact.” The evidence is not nearly so reassuring.In any outbreak, the single most important question is: How does it spread? The answer informs the guidance for everything else, including how to stay safe, which protective measures to put in place, and who should be notified during contact tracing. Get it wrong and everything else breaks down.[Read: ‘This is not going to be the next COVID’]We made this mistake at the start of the coronavirus pandemic, and the cost was high. Health officials thought the virus spread on surfaces (“fomite transmission”) and through large droplets that dissipate quickly and can’t travel six feet. That’s why we spent a full year cleaning elevator buttons and putting stickers on floors telling people where to stand. But these interventions did little to halt the spread of a disease that in fact traveled through small particles that lingered dangerously in poorly ventilated and enclosed spaces.We’re now getting it wrong again. “This is not a respiratory disease,” Mike Waltz, the U.S. Ambassador to the United Nations, said about the hantavirus in an ABC News interview on Sunday, adding, “It’s very rare to see it transmi