Hantavirus, Ivermectin, and the Dangers of the Internet

Back in March 2020, I did an interview with a CBS affiliate in Denver. While I was asked several questions about COVID-19 and pandemics in general, the interview was very short. To this day, I believe the most important piece of advice I shared didn’t make the cut: “Stay off the internet — it’s about to get really bad.” I’m about to, ironically, make the same point again 6 years later with a different virus scare.

The hantavirus outbreak is straight out of a horror movie written in the post-COVID pandemic world. Passengers mysteriously sickened on a cruise ship, some of whom died after disembarking. The cruise continues on without them. Then more passengers get sick. Finally, we find out that the mysterious illness can, in fact, be transmitted from person to person.

Once the news broke about the cruise ship hantavirus illnesses, deaths, and the prospect of person-to-person transmission, the internet did what it does best: spread rumors, speculation, and falsehoods. People started to panic that the next pandemic was here. Almost immediately claims also started circulating about ivermectin as a cure for hantavirus. For the record, this hantavirus outbreak won’t be responsible for the next pandemic, since human-to-human transmission is quite rare and requires prolonged close contact and exposure. But we’ve been here before with the panic and misinformation. Is May 2026 just March 2020 on steroids?

The Certainty Vacuum

People will consult the internet for a variety of reasons. Some are scared and looking for answers. Others are curious. And some see an opportunity — an opportunity to make a quick buck by claiming to sell the cure-all or a prevention tool for the new scary health event. This is also an opportunity to sow political doubt and mistrust, further advancing social discord. Indeed, the ghosts of the COVID-19 infodemic are back to haunt us again.

This exploitation is made possible by a “certainty vacuum.” While public health officials are still gathering data and using cautious, measured language, influencers fill the silence with definitive — and often dangerous — claims. In an attention economy, the internet rewards this projected confidence over nuanced expertise.

When people speak confidently about an evolving situation, that should raise alarm bells. Unless, of course, they have relevant expertise. In this case, listening to people who have studied hantavirus for years would be the kind of expertise to seek. Health influencers without that relevant expertise may have ulterior motives to stoke fear and panic.

We saw this playbook in action during the Los Angeles wildfires in 2025. Many influencers tried to capitalize on the quickly unfolding tragedy by focusing on the potential negative health effects. Multiple forms of “treatments” and “protection” remedies popped up in the form of supplements, essential oils, and more. The pattern is predictable: a crisis creates fear, fear creates a demand for immediate solutions, and influencers provide those solutions long before the evidence exists.

Hantavirus (specifically pulmonary syndrome) has a much higher mortality rate than either COVID or the wildfires. Scammers will try to prey on that heightened lethality. It’s what makes the danger feel more urgent, and it’s exactly what’s driving the “Ivermectin 2.0” wave. It’s all part of the misinformation playbook that physicians need to be aware of when interacting with patients.

Patient Communication

As you field questions about hantavirus, follow these steps for better information and communication with patients. And keep these in your back pocket for the next big health crisis too.

Encourage lateral reading. It’s important for patients to see what a variety of sources say about the same event. Remind them to remain skeptical of claims that are not reported across multiple sources and to stick to mainstream media sources, especially in the early hours, days, and weeks of an unfolding situation.

Use professional triangulation. If you look at pre-print servers, do so with extreme caution. While there are times that we must move forward with early-stage research and policy in uncertainty (e.g., COVID), ask if this is one of those times or if we can wait for consensus. Remember: peer review is a floor, not a ceiling, and in an emerging crisis, the speed of a study is often inversely proportional to its reliability.

Practice patience. While situations can quickly change, verifying facts takes time. Get comfortable with a potential prolonged timeline. It could take days, weeks, or longer. When discussing the data lag with patients, be sure to emphasize that what was true yesterday may be updated by tomorrow.

Educate patients about influencer overconfidence. Remind patients to be skeptical of influencers speaking confidently. In our attention economy, the internet rewards hot takes, but hot takes do not mean informed takes or expertise. Discuss how to prioritize both relevant expertise and facts.

Whether it’s smoke in the air or a virus on a cruise ship, the playbook for exploitation remains the same. To avoid falling for it, we must change how we consume information. I’ve argued that science communication needs to be a core competency in medical education and it’s for scenarios exactly like this. Addressing misinformation is not a secondary task in medicine; it’s now a necessary part of the job. If clinicians aren’t trained to communicate during the “gray space” of a crisis, they are essentially ceding the digital landscape to those who profit from panic.