Misinformation Definitions, Sources Continue to Evolve: K. "Vish" Viswanath, PhD

K. "Vish" Viswanath, PhD, a professor of population sciences at Dana-Farber Cancer Institute and a professor of health communication at Harvard T.H. Chan School of Public Health, discusses the definition and sources of misinformation in an interview at the American Association for Cancer Research Annual Meeting 2025.

He expanded on these points during his presentation, "Science for Everyone: Countering Misinformation and Building Public Trust," delivered yesterday as part of the session, "Using Communication Effectively to Foster Trust in Science, Cultivate Engagement, and Improve Clinical Trial Participation."

This transcript has been lightly edited; captions were auto-generated.

Transcript

For context, how do you define health misinformation? How has it evolved in recent years, especially with the rise of digital platforms?

Health misinformation is not new. In fact, if you go back to the history of media, some of the earliest misinformation examples come from health. We used to call them snake oil salesmen because they would sell snake oil, literally, as a panacea for all kinds of ills. It's a long history, but over time, it has evolved.

It has evolved in a way because of the complex information ecosystems that we are in. From pamphlets and rags, virtually, newspapers, as we used to call them, to now a complex system of both electronic media, social media, internet, as well as interpersonal channels, as we call them: friends, family members, colleagues, coworkers, etc.

Then, what is misinformation? The way we define misinformation is information or claims about science or health that are in variance from the scientific consensus on that topic at that time. What claims are considered misinformation will change over time, as science itself will evolve. We are recognizing the fact that the definition of what is misinformation could potentially change as science evolves.

What are the most common sources of misinformation? Are there certain health topics, conditions, or disease states that are targeted more frequently?

It might surprise the audience that misinformation can be spread both intentionally and unintentionally. When you say common sources, we have to say, unintentionally, it could be spread by scientists when they simplify a story. It could be spread by press offices when they write a press release because, in a press release, you do not write all the limitations of the study. It could be [spread] by other well-intentioned actors who are trying to help other people, right?

But it could be spread intentionally and deliberately by governments, or government spokespeople; by certain interest groups who are interested in, say, the modern-day version of snake oil; or people who have ideological, religious, or other motivations, or even monetary motivations, to intentionally spread misinformation.

As for what topics are appealing, any topic. There are a wide variety of topics out there. Certainly vaccines; I'm sure you're hearing, the listeners are hearing, a lot about vaccines. Vaccines are a good, when I say good, I mean a fertile topic for spreading misinformation. Cancer is another area because of the complexity.

It [misinformation] is most likely to emerge on topics where the science is not settled yet. COVID-19 is a good example, which was an evolving scientific subject that was very ripe for misinformation.