Vaccine Misinformation Outpaces Efforts to Counter It

Misinformation about vaccines has proliferated on social media where it has led to rising levels of vaccine hesitancy at a faster rate than interventions are addressing it, according to a study led by a researcher at Columbia University Mailman School of Public Health. Some interventions to counter vaccine misinformation on social media have been beneficial, but very few test their effect on real-world behaviors. The findings are published in the peer-reviewed journal BMJ.

Researchers reviewed existing research on the links between social media misinformation (false, inaccurate information promoted as factual) and vaccination rates, as well as the effectiveness of social media countermeasures. They present a roadmap for researchers and policymakers to produce more effective countermeasures.

Anti-vaccine misinformation is as old as vaccines themselves, but anti-vaccine campaigns have proliferated in recent years on social media—particularly since the start of the COVID-19 pandemic. This misinformation targets all kinds of vaccines, including childhood vaccines, COVID-19, flu, HPV, and more. While vaccine hesitancy can stem from many sources, including mass media and political rhetoric, as well as genuine safety concerns, there is ample evidence that a proliferation of anti-vaccine messages on social media increased vaccine hesitancy and lowered vaccination rates over the same period that social media networks expanded. The return of measles after aggressive antivaccine campaigns prompted the World Health Organization to list vaccine hesitancy among the greatest threats to global health.

Campaigns to promote vaccine uptake and reduce hesitancy take various approaches, such as debunking (fact-checking specific claims after they have reached social media users) and “prebunking,” in which users are taught about how “fake news” works before exposure. Other intervention types include warning (“inoculating”) people about manipulation tactics, and using accuracy prompts to trigger people to consider the truthfulness of material they are about to share on social media platforms, without stopping them from posting.

The new study presents findings from studies of several types of these campaigns, targeting a variety of groups and types of vaccines. Their effectiveness were mixed. Key takeaways:

• The high volume of misinformation appearing online can override more reliable sources, limiting the effectiveness of high-quality information campaigns.
• Simply banning misinformation on social media can backfire and actually drive people to seek out even less moderated sources of information. Similarly, debunking efforts have mixed results; they can counter misinformation but also can deepen false beliefs.
• Successful messaging typically affirms cultural values (e.g., autonomy of choice, protection of loved ones, common beliefs) and addresses their reasons for hesitancy—not only facts about vaccine benefits and harms.
• Trust is a crucial component of successful campaigns. Trusted voices (influencers) include community health workers, faith leaders, and members of the U.S. military.
• Content labeling and corrective actions by social media platforms have produced some positive effects, but they should be more proactive in addressing misinformation.

Lead author Kai Ruggeri, PhD, professor of health policy and management at Columbia Mailman School, and his co-authors argue that a crucial step towards developing more effective interventions is the close monitoring of public perceptions and opinions about vaccination. Behavioral researchers must partner with social media companies to analyze large quantities of “social listening data” in real time. (Unfortunately, these partnerships face a headwind of social media platforms’ declining interest in vaccine misinformation countermeasures since the height of the pandemic—none more so than X, formerlly Twitter.) Also important are partnerships between researchers, health care clinics, and public health agencies, to understand the effects of interventions on vaccinations.

Promoting vaccination takes a strong investment in public health, both online and off, including in-person outreach by community health workers and faith leaders, and a broad network of vaccination locations. However, the authors say, it is crucial to address the proliferation of misinformation about vaccines where it is happening—on social media.

“Social media platforms are the epicenter of misinformation. They also need to be part of the solution,” says Ruggeri. “Misinformation is not new and its noxious consequences are not insurmountable, but its effect on vaccine hesitancy through social media is an urgent global threat to public health.”

Study co-authors represent six continents and an accomplished team with members who include Samantha Vanderslott, an associate professor with the Oxford Vaccine Group, Centre for Clinical Vaccinology and Tropical Medicine, Churchill Hospital, NIHR Oxford Biomedical Research Centre; Mosoka P. Fallah, program manager, Saving Lives and Livelihoods, Africa Center for Disease Control, Addis Ababa, Ethiopia, and one of the “Ebola Doctors” named as Time’s Persons of the Year in 2014; and Ralph Hertwig, celebrated behavioral scientist and professor at the Max Planck Institute for Human Development, Berlin.  A full list of authors is available in the journal article linked above.

The authors report no competing interests.