Hantavirus Outbreak: Misinformation Spreading Faster Than the Virus

Public health experts are sounding the alarm about the rapid spread of hantavirus misinformation, which now follows a predictable pattern that emerged during the COVID-19 pandemic.

Within hours of reports about a hantavirus outbreak linked to the expedition cruise ship MV Hondius, social media was flooded with false claims and conspiracy theories. Dr. Katrine Wallace, an epidemiologist at the University of Illinois Chicago School of Public Health, first learned about the misinformation through her social media followers who began sending her screenshots.

“One was from the account of a Texas doctor who became well known during COVID for promoting ivermectin. She was already telling followers that ivermectin would work against hantavirus, too,” Wallace explains. Her inbox quickly filled with messages from worried parents and people who had already been advised by family members that ivermectin was the solution.

The actual outbreak is serious but limited in scope. Eight cases have been linked to the MV Hondius cruise ship, with three fatalities reported so far. The strain involved, Andes hantavirus, is the only hantavirus known to spread person-to-person, though it generally requires prolonged close contact. The World Health Organization currently assesses the broader public health risk as low.

Medical experts emphasize that no specific antiviral treatment exists for hantavirus, with supportive care being the standard approach. Contrary to circulating claims, ivermectin has not been proven effective against hantavirus.

However, the facts of the outbreak quickly became secondary to the spread of misinformation. Within a day, social media accounts were claiming the outbreak had been caused by COVID vaccines. Former Rep. Marjorie Taylor Greene amplified the conspiracy, suggesting pharmaceutical companies “manipulate the virus, make the vaccine, and then make the profits.” Other accounts warned against a nonexistent hantavirus vaccine or labeled the outbreak as either a pharmaceutical scheme or a Chinese bioweapon.

“The claims contradict one another constantly. That doesn’t slow them down at all,” Wallace observes.

Health misinformation no longer appears as random rumors but functions more like an infrastructure—a network of influencers, conspiracy accounts, partisan personalities, and monetized content creators who rapidly attach themselves to any new health scare. The cycle follows a predictable pattern: identify a new disease, distrust official explanations, assume a cover-up, mention alternative treatments like ivermectin, suggest hidden profit motives, and repeat.

During COVID, this process sometimes took weeks to build momentum. Now it happens within hours. Scientists on social media were even joking about imminent conspiracy claims before the first major misinformation posts had appeared.

One particularly troubling example circulating involved a social media prediction from 2022 stating: “Corona ended, 2026: Hantavirus.” This was being framed as evidence the outbreak had been planned years in advance, despite the fact that conspiracy accounts make countless predictions, with most being wrong and forgotten.

What concerns public health experts most is the psychological impact of these repeated cycles on the public. Recent Pew Research data found that half of Americans under 50 now get health and wellness information from influencers and podcasts, many of whom present themselves as medical experts despite lacking relevant credentials.

“When a future outbreak with real pandemic potential eventually emerges, and one will, millions of people will encounter it inside an information environment already primed to distrust public health guidance before it even arrives,” Wallace warns. “The narratives are prewritten now. The audience already knows the cues.”

The most alarming aspect isn’t simply that misinformation exists—it’s that society has started treating this toxic information environment as normal, potentially undermining future public health responses when they’re needed most.