Everything had been leading to the meeting early last year in Zanzibar, a tropical archipelago off the east coast of Africa.
A hundred researchers, clinicians and other experts on HIV from across Africa and beyond were there to discuss big plans — the development of an innovative vaccine on the continent that could prevent the disease, which continues to infect and kill people disproportionately in sub-Saharan Africa.
And they had big money to do it. This group, called the BRILLIANT Consortium, had landed a $45 million grant from the U.S. Agency for International Development (USAID) in 2023.
"I mean, it's unprecedented," says Nonhlanhla Mkhize, a medical scientist with the National Institute for Communicable Diseases (NICD) in Johannesburg, "having a consortium that is made up of African scientists working toward an African problem in our labs here in Africa."
Year one of the five-year grant had been almost entirely virtual. Now, they were all here together in Zanzibar and ready to turn their expertise into action. All the presentations and discussions and arguments had coalesced around a solid plan to thwart the virus. The scientific advisory board endorsed the imminent launch of the vaccine trials.
"I remember the excitement was through the roof," says Mkhize. "We were at the beginning of something big."
But just as the meeting was about to wrap up, the mood darkened.
A new executive order signed by President Trump on the day of his inauguration, Jan. 20, 2025, had frozen all foreign aid pending a review. Soon, DOGE would begin its decimation of USAID — cutting programs, interrupting funding streams, letting people go, and generally sowing uncertainty within an agency that, for more than six decades, had provided global humanitarian aid and development assistance.
The disruptions were starting to ricochet around the world, including at that gathering in Zanzibar.
"I remember at the end of the meeting, a USAID colleague saying to me, 'I'm not sure if I'll see you again,'" says Penny Moore, a virologist at the University of the Witwatersrand in South Africa. "I completely underestimated how much it would gut the program."
Shortly afterward, the official stop work orders were issued.
"That was crushing because we were about to enroll our first participants within the trial," says Moore. "It takes months and months and months to gear up for a clinical trial. [But] you can shut it down almost immediately."
"I don't think any of us knew what was going to happen," says Dale Kitchin, a senior scientist at NICD. "There was generally a sense of alarm."
This story might have ended here.
"In many ways, we've kind of had our legs cut off even as we're beginning to run the sprint," says Linda-Gail Bekker, who directs the Desmond Tutu Health Foundation at the University of Cape Town, one of the collaborating partners under the USAID grant.
Instead, the team steeled their resolve. They knew the science was sound and the need was urgent. They insisted on finding a way forward.
There's no sugar-coating the problem
This was all happening, according to Moore, at a critical time in the fight against HIV. She doesn't believe that treatments alone — including the recent introduction of lenacapavir, a twice-yearly injectable — will be enough. "We need to get to the point where we are finally ahead of the virus, and I think that the only way we can do that is through a vaccine," she says.
Moore has been studying HIV for over 20 years, slowly piecing together a detailed portrait of the virus. Research on HIV by her and others has also taught scientists about how the human immune system functions more generally, which has facilitated advances against other ailments including COVID-19, RSV and cancer.
A good portion of Moore's work has been supported by the U.S. In her lab in Johannesburg, pieces of equipment, including refrigerators and centrifuges purchased with funds from USAID, have stickers from the agency plastered on them. Some contain the phrase: "from the American people."
The reason, says Moore, is "so that we remember who bought them for us."
In addition to the equipment, Moore's research has relied on a group of 117 South African women who have contributed their blood regularly to her lab for 20 years.
"The people who are donating these samples live in the communities most ravaged by HIV," she says. "And they donate because they hope to see an end to an epidemic that is really real for them."
The 20 years of samples are stored in a room arrayed with half a dozen large freezers. This is, essentially, Moore's career on ice. She cracks open the lid of one and pulls out a stack of frozen tubes.
"This is blood and cells and DNA," she says. "It's heavy and hard for me to lift. The amount we have learned from these freezers, it's just astonishing."
Those findings include answering questions that helped lead to the vaccine that Moore and her team were about to start testing under the USAID grant, like — why is HIV so skilled at evading our bodies' defenses?
"It's like an M&M, in that it's completely covered by sugars," Moore explains. "And sugars are essentially invisible to the immune system. So it's very difficult for the immune system to see the virus at all." While other viruses, including the one that causes COVID-19, deploy these sugary shields to a lesser extent, Moore says HIV is the most accomplished when it comes to hiding within and from the human body.
In addition, HIV is remarkably variable. The virus mutates frequently, making "every mistake it can every single day," says Moore. But not all mistakes are bad. "Very quickly, every mistake that survives turns into a swarm of viruses within one person, and they're all different from one another."
This allows the virus to evolve in different directions in different places, including within Africa. "The virus that they have in Kenya is not the same as the virus that we have in Botswana," she says. "It's not the same as the virus that they have in Senegal."
This diversity was a big reason why Moore was so excited to be working with colleagues from different African countries under the USAID grant. It would have allowed the testing of vaccine candidates on a range of flavors of the virus in different populations on the continent.
As for the vaccine itself, its origins began with a key insight that came out of Moore's lab, in part. A few years after becoming infected with HIV, a small fraction of the people donating blood developed something called broadly neutralizing antibodies.
These are "the kinds of antibodies that can recognize and neutralize a virus regardless of where that virus comes from," says Moore. "And in many cases, up to 90% of global viruses could be stopped by one antibody."
Broadly neutralizing antibodies are weird looking. "They're all freaks of nature," allows Moore. Some have really long arms. Some have super short arms. Their oddness gives them a way of dealing with that sugary exterior to get to the virus hiding within, which Moore likens to the chocolatey interior of the M&M.
When these rare antibodies appear naturally, they usually emerge too late to be of assistance to the person living with HIV. "The virus has already spread too much and they actually don't have such an effect," says Nigel Garrett, the chief scientific officer at the Desmond Tutu Health Foundation.
"So we need to bring it forward before someone gets infected — catch the virus before it enters the bloodstream," he adds, explaining the vaccine development strategy. "That is a journey. You have to prime the immune system, you have to then shepherd the immune system along and then you have to polish it to ensure the [production of] the right antibody against the circulating HIV viruses."
But because the antibodies are so strange, it's very difficult to coax the body to produce them in response to a vaccine. This is what the USAID grant was intended to do — set up a series of trials that could flexibly and quickly work out the best way to encourage the immune system to create legions of these special antibodies.
"We know what we're trying to do," Moore says. "I'm not saying we're around the corner. It's a tough virus, but I feel like we're closer than we have ever been, and that's why I'm so frustrated."
Finding a way forward again
After the cancelation of the USAID grant, everyone was just reeling.
"There were a lot of hugs and there were a lot of tears and there was a lot of swearing on my part," says Moore.
No one wanted to scrap the vaccine project. "A devastating thing, a funding cut, yes, but we will always find a way to come back fighting," says Sheetal Kassim, the Senior Research Officer with the Desmond Tutu Health Foundation. "We are fighters."
So the South African researchers on the team came up with an alternate plan.
They realized they'd have to scale back — make it a South Africa initiative only and reduce the scope of the trials. But they believed in the promise of what they had proposed, and they knew there was no time to waste. "It's important to keep the momentum going until we get to a stage where we have the epidemic under control," says Garrett.
For Amelia Mfiki, the community liaison officer for the vaccine trials, the bottoming out of the USAID funding was a wakeup call.
"This is a great opportunity for South Africa to prove that we can do things in South Africa for South Africa with South African financing," she says. "We still need support from other countries, but we shouldn't be depending solely on them."
Still, there were many late nights and a lot of unease. "We were frantically writing grants to everybody who would have us — literally, any funder in any country on whether they might be willing to support the program," says Moore.
Ultimately, the project secured funding from the South African Medical Research Council and the Gates Foundation (which provides financial support to NPR). It's about a twentieth of the original USAID grant and none of it is from the U.S. government.
The State Department did not respond to a request for comment about the withdrawal of funding for the trial and the possibility of future funding of such endeavors.
Now, after nearly a year of delays, screening of participants for the pared-down trials has begun.
On the outskirts of Cape Town, a factory building stands tall in Philippi Village, an impoverished township where HIV is rampant.
"It's important to do the work not in these communities — but with these communities — because these are the communities that are most affected by HIV," explains Kassim. This is "where the disease burden is highest."
The factory has been converted into a multi-use space. Mfiki makes her way to a room where 20 or so young women are waiting. "I will explain to them the criteria and who should join the trial," she says. "And this is the community that we recruit on and look for potential participants in."
The women listen attentively to Mfiki as she speaks. She knows that over the years, their participation and that of others from their community has been critical for trialing treatments for HIV — which now includes vaccine candidates.
"Communities and participants are equal partners to the researchers and to the research itself," she says. That's because without participants, there can be no trials and progress against HIV will stall out.
Nandipha Mongo is one of the women attending today's meeting. She was part of another HIV trial recently, so she's not eligible to join the new vaccine trial. Still, Mongo, who's 25 years old, says she was very glad to be involved with this research.
"I'm over the moon, man!," she says proudly, acknowledging that she's making "a big difference."
Mongo's community struggles with gender-based violence and unplanned pregnancies. HIV is forever stalking them. "Most of us are scared of getting HIV," she admits.
For her, a vaccine against the virus would mean one thing — "living free," she says.
The first shots of the new trial start going into participants' arms next week.
This story was supported by a grant from the Pulitzer Center.
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