The window for pre-bunking is open right now.
In South Africa, where a twice-yearly HIV prevention injection called lenacapavir holds the promise of dramatically reducing new infections, researchers at Wits University are confronting an older and more stubborn adversary than the virus itself: the misinformation that travels faster than any medicine. Drawing on the logic of vaccination, they are inoculating minds before false claims about organ failure and fatal harm can take root among the young women who stand to benefit most. The window is narrow, the stakes are generational, and the lesson from Covid-19 is unambiguous — a cure that communities fear is a cure that fails.
- Lenacapavir could nearly eliminate HIV transmission, but safety myths claiming it causes liver, kidney, and heart failure are already circulating among young South African women before the drug has even reached them.
- A visible injection nodule under the skin gives misinformation a rare and dangerous weapon — something that can be photographed, captioned, and shared, turning a minor side effect into apparent proof of harm.
- Wits researchers tested short, TikTok-style 'pre-bunking' videos that exposed false claims alongside explanations of manipulation tactics, and found they raised vaccine acceptance intentions by 13% even among those most resistant to health interventions.
- The intervention works best on the hardest-to-reach — people who already refused the Covid-19 vaccine — but two videos cannot substitute for the coordinated effort across health departments, NGOs, and community workers that real scale demands.
- The pre-bunking window is open now; once misinformation embeds itself in social networks and family conversations, correcting it becomes exponentially more difficult.
A twice-yearly injection called lenacapavir is arriving in South Africa with the potential to essentially eliminate HIV transmission — but researchers who study health behaviour know that a drug's efficacy means little if communities won't accept it. At Wits University's Health Economics and Epidemiology Research Office, a team has been mapping the false claims already forming around lenacapavir and future HIV vaccines. What they found upended their expectations: rather than conspiracy theories about population control, the misinformation most powerfully deterring young South African women centred on catastrophic physical harm — claims that the drug causes liver failure, kidney failure, heart failure, bone marrow damage, cancer.
The pattern echoes the Covid-19 rollout, when nearly 40 percent of the most resistant South Africans believed the vaccine could be fatal. The mechanism is grimly predictable: when millions are vaccinated in a short window, some die from unrelated causes, coincidences become stories, and stories become social media posts. Once a frightening claim lodges in someone's mind, factual correction struggles to displace it. Lenacapavir carries an additional vulnerability — it can leave a visible nodule under the skin, something that can be photographed and shared, making it nearly a perfect hook for false claims.
To get ahead of this, the Wits team tested psychological inoculation, or pre-bunking: exposing people to a weakened dose of misinformation in a controlled setting, using humour and clear explanation of manipulation tactics, before they encounter the real thing. Working with production company Reel Epics, they created 2.5-minute TikTok-style videos — scripts workshopped with young women from HIV service organisations, who told them bluntly to strip out the academic language or no one would watch past five seconds.
In a trial with over 2,000 women aged 18 to 29, the results were striking. Those who watched the pre-bunking videos actually increased their intentions to accept a future HIV vaccine after being shown misinformation, while those who saw only the misinformation reported intentions 13 percent lower. The effect held three weeks later, and worked best among people who had already refused the Covid-19 vaccine — precisely those most in need. The videos have since been adapted for lenacapavir and are freely available on social media, with a new study underway. But the researchers are clear-eyed: reaching women in communities where health conspiracy theories already run deep, women less connected to digital platforms, requires serious coordination across health departments, NGOs, and community health workers. The window for pre-bunking is open now — once misinformation goes viral, dislodging it becomes exponentially harder.
A new HIV prevention drug is arriving in South Africa with extraordinary promise: lenacapavir, an injection given twice a year that essentially eliminates the risk of infection. But the researchers who study how people actually use health products know that efficacy alone doesn't guarantee uptake. Misinformation does the real damage—it lives in the gap between what a medicine can do and what communities will actually accept.
At Wits University's Health Economics and Epidemiology Research Office, a team led by researchers studying health behaviour has been mapping the false claims already beginning to circulate about lenacapavir and future HIV vaccines. What they found surprised them. They expected conspiracy theories to dominate—claims about population control, about foreign governments engineering harm against Black women. Instead, the misinformation that most powerfully deters young South African women from accepting HIV prevention tools centres on catastrophic physical harm: that the drug will kill you, that it causes liver failure, kidney failure, heart failure, bone marrow damage, cancer. Safety fears, not conspiracy, topped the list.
This pattern mirrors what researchers observed during the Covid-19 vaccine rollout. Nearly 40 percent of the most resistant people in South Africa believed the vaccine could be fatal. The mechanism is simple and relentless: when millions of people are vaccinated in a short window, some will die from unrelated causes. Those coincidences become stories. Stories become social media posts. Posts circulate among friends and family. And once a vivid, frightening claim lodges in someone's mind, a later correction struggles to displace it. Human brains process emotional narratives far more powerfully than factual rebuttals.
Lenacapavir faces particular vulnerabilities. Many people will confuse it with a vaccine—after all, it's an injection you take to prevent disease. But it works entirely differently. A vaccine trains your immune system to produce antibodies; lenacapavir blocks HIV from entering cells and only works while someone continues taking it. Misinformation about vaccines in general could layer onto misinformation about lenacapavir itself, compounding the problem. There is another risk that genuinely concerns researchers: the injection can leave a visible nodule or bump under the skin. Most drug side effects are invisible. This one can be photographed, captioned, shared. A visible lump is nearly a perfect hook for false claims.
To counter this threat before it spreads, the Wits team tested an approach called psychological inoculation, or pre-bunking. The concept mirrors medical vaccination itself: expose people to a weakened dose of misinformation in a controlled context—using humour, clear explanation of manipulation tactics—before they encounter the real thing in the wild. The goal is to build cognitive antibodies, mental tools that help people recognize and resist false information.
Working with the production company Reel Epics, researchers created 2.5-minute videos in TikTok style featuring false claims alongside explanations of why they were false. Crucially, they workshopped the scripts with young women from HIV service organizations, who told them bluntly that their first drafts needed to be "de-Harvardised"—stripped of academic language or nobody would watch past five seconds.
In a trial with over 2,000 young South African women aged 18 to 29, the results were striking. Those who watched the pre-bunking videos actually increased their intentions to accept a future HIV vaccine after being shown misinformation. By contrast, those who saw only the misinformation without the inoculation video reported intentions 13 percent lower. Participants who saw the videos were also less likely to say they would share the misinformation if they encountered it online. The effect persisted three weeks later. Most importantly, the videos worked best among people who had already refused the Covid-19 vaccine—precisely the group most vulnerable to misinformation and most in need of support.
The team has already adapted the videos for lenacapavir itself, using the same format and persuasion framework. Organizations promoting the drug are now sharing them on social media, freely available for anyone to use. A new study is underway, focused specifically on lenacapavir misinformation and reaching a more economically diverse sample. But the researchers are clear-eyed about the limits of their approach. Two well-designed videos cannot solve a misinformation crisis alone. Scaling this intervention to reach women in communities where health conspiracy theories already have deep roots, women less connected to digital platforms, women whose decisions are shaped by what they hear in their immediate networks—that requires serious investment and coordination across the health department, NGOs, and community health workers. The window for pre-bunking is open now, before false claims become entrenched. Once misinformation goes viral, the work of dislodging it becomes exponentially harder.
Notable Quotes
Our first scripts needed to be 'de-Harvardised'—stripped of academic language before anyone would watch them past the first five seconds.— Young women from HIV service organizations, during video development workshops
Misinformation doesn't arrive after a product launches. It grows in the space between excitement and access, between announcement and take-up.— Wits researchers on the timing of pre-bunking intervention
The Hearth Conversation Another angle on the story
Why does safety fear beat out conspiracy theory? I would have guessed the opposite.
Because safety fears feel personal and immediate. A conspiracy theory requires you to believe in a hidden agenda. A safety fear just requires you to imagine your own body failing. When someone tells you a drug causes heart failure, you don't need to believe in a plot—you just need to picture yourself in a hospital bed.
And the visible nodule—you seem genuinely worried about that.
I am. Most side effects are invisible, so they stay abstract. A lump under your skin is concrete. It can be photographed. Once images start circulating with captions like "look what this does to you," the clinical reality doesn't matter anymore. The image is the message.
The videos worked best on people who refused the Covid vaccine. That seems backwards.
It's not. Those people are already skeptical of health authorities and official narratives. They're the hardest to reach through traditional channels. But if you meet them with a video that acknowledges the misinformation exists, explains how it manipulates you, and does it in a way that respects their intelligence—suddenly you're not lecturing them. You're giving them tools to think for themselves.
What happens if the videos don't scale?
Then you have a drug that works but that people won't take. The gap between what a medicine can do and what communities actually do with it is where epidemics are lost. That's not a failure of the drug. It's a failure of the information environment.