Editor’s note: This story was first published on March 26, 2025.
We could see up to 10.8 million more HIV cases than anticipated in the next five years if planned cuts to international HIV funding take place.
This surge in infections in low- and middle-income countries would contribute up to 2.9 million more HIV-related deaths by 2030.
These disturbing figures come from a new modeling study published March 26 in the journal The Lancet HIV. The researchers wanted to analyze the potential impact of cuts to international funding for HIV/AIDS programs, which work to prevent both transmission and deaths related to the infection.
As of February 2025, the five top donors of this funding — the United States, United Kingdom, France, Germany and the Netherlands — have all announced significant cuts to foreign aid that threaten HIV programs worldwide. The study predicts how these cuts would impact low- and middle-income countries (LMICs), which since 2015 have relied on international sources for 40% of their HIV program funding.
“These findings are a sobering reminder that progress in the fight against HIV is not guaranteed — it is the result of sustained political will and investment,” said Dr. Ali Zumla, a professor of infectious diseases and international health at University College London who was not involved in the research.
But equally, “the projected surge in new infections and deaths is not an inevitability; it is a consequence of choices being made today,” Zumla told Live Science in an email. “If these funding cuts move forward, we risk unraveling decades of hard-won progress, leaving millions vulnerable and pushing global HIV goals further out of reach.”
Related: We could end the AIDS epidemic in less than a decade. Here’s how.
Unprecedented cuts to aid
As of 2023, five donors have supplied more than 90% of the international funding for HIV programs, with the United States providing over 72% of the total. Specific populations at high risk of HIV — including people who inject drugs, men who have sex with men, female sex workers and their clients, and transgender and gender diverse people — particularly rely on these international funding sources for access to HIV prevention and testing.
Much of the U.S. funding comes from the President’s Emergency Plan for AIDS Relief (PEPFAR), which is largely implemented by the Agency for International Development (USAID). However, PEPFAR and USAID were hit by an unprecedented funding pause and staffing reduction in January, following an executive order from President Donald Trump.
PEPFAR later received a temporary waiver to continue some services, including those for antiretroviral therapy (ART), the drugs that keep HIV from progressing to AIDS. These treatments must be taken consistently or the virus will rebound.
“The widespread rollout and uptake of antiretroviral therapy funded by international sources has been one of the most important factors reducing AIDS related deaths in lower income settings,” said Justin Parkhurst, an associate professor of global health policy at the London School of Economics and Political Science who was not involved in the study. ART also cuts the number of new infections by suppressing the virus in people living with HIV, thus preventing transmission, he told Live Science in an email.
“In the worst-case scenario, if PEPFAR funding were ceased entirely and no equivalent mechanism replaced it, surges in HIV incidence could potentially undo nearly all progress achieved since 2000.”
ten Brink, et al. (2025)
However, despite the waiver, PEPFAR’s services still haven’t resumed as normal, given the waiver didn’t trigger immediate funding to eligible programs and many clinics had already shuttered by the time it was issued. Even now, PEPFAR’s future after the waiver’s expiration remains uncertain.
Following the U.S., the next top four donors for international HIV funding are the U.K., France, Germany and the Netherlands. However, as of February 2025, each of these donors has also announced major cuts in foreign aid spending — “and more might follow,” the study authors wrote.
Based on the projected cuts being made by the top five donors, the researchers used a mathematical model to predict the rates of new HIV cases and deaths. They focused their model on 26 LMICs, which together receive 49% of international HIV aid, overall, and 54% of PEPFAR aid. They then used the data from these 26 countries to extrapolate to all LMICs worldwide.
Cuts could “undo nearly all progress achieved since 2000”
The researchers considered several scenarios in their model. The first — the “status quo” — served as a baseline, projecting the rates of cases and deaths if recent levels of HIV spending were maintained between 2025 and 2030, rather than cut. In this scenario, more than 1.8 million new infections and over 720,000 HIV-related deaths occurred in LMICs.
In the worst-case scenario the team considered, all PEPFAR funding was indefinitely stopped on Jan. 20, 2025, and no alternative funding sources emerged to fill that gap. Simultaneously, other, non-PEPFAR sources of international funding were also reduced. That scenario led to an estimated 10.8 million more cases and 2.9 million more deaths than the status quo.
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This suggests that “the number of new infections in 2026 could return to 2010 levels, and by 2030 the number of new infections could surpass historical estimates,” the study authors wrote. “In the worst-case scenario, if PEPFAR funding were ceased entirely and no equivalent mechanism replaced it, surges in HIV incidence could potentially undo nearly all progress achieved since 2000.”
This worst-case scenario would hit sub-Saharan Africa (SSA) particularly hard — out of eight SSA countries included in the analysis, six receive over 40% of their HIV funding through PEPFAR. Children in the region could see a nearly three-fold increase in HIV infections, the authors predicted.
And outside of SSA, other vulnerable populations, such as sex workers, would be much harder hit by such cuts than the general population, showing up to a six-fold higher increase in cases than other demographics, the data suggested.
The team also looked at a less extreme scenario, modeling what would happen if new funding sources filled the gap left by PEPFAR. In this scenario, they assumed that the gap could be partially filled by 2026 and then fully filled by 2027. If that mitigation were to happen, the number of extra cases drops to 4.4 million and the extra deaths to 770,000 over the course of five years.
So while filling the gap left by PEPFAR would help substantially, that sudden loss of funding would still have devastating impacts, the study suggests.
“Modelling reveals the potential for severe consequences following abrupt stopping, with no notice, of international support aimed at stopping AIDS as a global public health threat,” Dr. Catherine Hankins, a professor of global and public health at McGill University in Canada who was not involved in the study, told Live Science in an email.
Cuts could be felt for decades to come
According to the study authors, even if the PEPFAR gap could be filled within two years, the ripple effects would be felt for decades to come. They estimated that it would take 20 to 30 extra years of 2024-level funding to end AIDS as a public health threat.
Ambitious goals set by UNAIDS have aimed to end the threat by 2030. And historic HIV trends suggested that many of the LMICs featured in the new paper could have hit their targets by about 2036, if funding continued at past levels, the authors wrote.
“This study indicates that an abrupt termination of programmes has serious risks to human life,” Parkhurst said. “Even for those who believe the US or other governments should reduce foreign aid spending in this area, there can be planning around how to do so without producing serious harm to millions of people around the world who have come to rely on the treatment.”
The study suggests that, if that abrupt stop could be avoided, many lives could be spared.
The researchers looked at what would happen if PEPFAR was reinstated or “equivalently recovered” and estimated that there could be 70,000 to 1.73 million extra cases and 5,000 to 61,000 extra deaths, compared to status quo. Those estimates assume that other international funding will still be reduced, but that countries will be able to make up for some of the lost funds domestically.
The new study has some limitations, as “there is inherent uncertainty in global modelling,” said study co-first author Rowan Martin-Hughes, a senior research officer at the Burnet Institute in Australia.
The “most important” limitation is that there is uncertainty in the HIV fiscal space, although the authors covered some of that unpredictability by looking at a range of possible outcomes, Martin-Hughes told Live Science in an email. There are also gaps in the global reporting of financial data that could affect their model, and the 26 featured countries might not be fully representative of the overall impacts of funding cuts, he added.
However, “overall, we think most sources of uncertainty are likely to result in underestimating rather than overestimating the real effects of immediate and severe funding cuts to HIV programmes globally, especially in the sub-Saharan African region,” he said.
In light of the impending cuts, “it is paramount now to track AIDS mortality and HIV incidence while urgently reversing the cuts, mitigating the effects, and creating new funding strategies to prevent further suffering,” Hankins said.
Martin-Hughes agreed.
“Governments, donors, and stakeholders must collaborate on feasible mitigation strategies to preserve HIV prevention, testing, and treatment services to avoid a resurgence in the HIV epidemic,” he said. “In doing so, the global community can secure both the immediate and long-term stability of resilient health systems so integral to saving lives through HIV epidemic control.”
Global investment, especially from the U.S., has put targets for the elimination of HIV transmission within reach, he said. “But all of that progress is vulnerable, and could be wiped out within a few years if there are dramatic and unmanaged cuts to HIV services.”
