Funding cuts by countries that make major contributions to foreign aid may cause surges in global HIV.
Cuts could cause an additional 4.43-10.75 million new HIV infections worldwide by 2030.
Sub-Saharan Africa may experience the biggest effect.
Funding cuts by five countries that provided over 90% of total international HIV funding as of 2023 may lead to millions more HIV deaths and new HIV infections globally over the next 5 years, a modelling study showed.
The U.S. paused all aid as of Jan. 20, 2025, and proposed reductions in aid from the U.K., France, Germany, and the Netherlands may lead to a projected 24% reduction in HIV funding to low- and middle-income countries (LMICs) by 2026.
Increases in new HIV infections and HIV-related deaths resulting from these cuts -- including the discontinuation of President's Emergency Fund for AIDS Relief (PEPFAR) -- will be substantial in those countries receiving international funding, according to Debra ten Brink, MD, MPH, of the Burnet Institute in Melbourne, Australia, and colleagues.
Between 2025 and 2030, these cuts could cause an additional 4.43-10.75 million new HIV infections worldwide and an increase of 770,000 to 2.9 million in HIV-related deaths in children and adults, they wrote in The Lancet HIV.
"The United States has historically been the largest contributor to global efforts to treat and prevent HIV, but the current cuts to PEPFAR and USAID-supported programs have already disrupted access to essential HIV services including for antiretroviral therapy and HIV prevention and testing. Looking ahead, if other donor countries reduce funding, decades of progress to treat and prevent HIV could be unraveled," ten Brink said in a news release.
"It is imperative to secure sustainable financing and avoid a resurgence of the HIV epidemic which could have devastating consequences, not just in regions such as sub-Saharan Africa, but globally," she added.
In an accompanying editorial, Euphemia Lindelwe Sibanda, PhD, of the Center for Sexual Health and HIV/AIDS Research in Harare, Zimbabwe, and Andrew Phillips, PhD, of the University College London in England, suggested possible short- and long-term adaptations and adjustments to mitigate funding cuts.
Measures could include a more robust supply chain for drugs, more efforts to prevent product loss or waste, the use of long-acting injectable drugs for treatment, and increased domestic funding for HIV response, Sibanda and Phillips wrote.
The study by ten Brink and colleagues projects "sobering increases in new HIV infections and deaths," they stated. "It is important for programs to implement both short-term and long-term interventions for preventing these grave outcomes and reversal of gains made since the year 2000."
The researchers used a 26-country validated mathematical model (Optima HIV) to project the incidence of mortality across 2025-2030 for various scenarios, including best- and worst-case scenarios. They also estimated additional effects on treatment and facility-based testing caused by immediate discontinuation of support from PEPFAR.
They found that as soon as 2026, if foreign aid is reduced or PEPFAR is stopped completely with unsuccessful efforts to mitigate the losses, the number of new HIV infections and HIV-related deaths may return to levels not seen since 2010.
"Our research indicates a high resurgence of new HIV infections and deaths in low- and middle-income countries, but as we saw in the beginning of the HIV epidemic, this is likely to become a global issue," ten Brink told MedPage Today. "In resource-constrained settings, clinicians may see limited access to antiretroviral therapy, prevention programs, and disruption of testing services. Globally, this could mean clinicians will be seeing more new cases of HIV in their practice worldwide, potentially as late presentations as well, due to delayed testing."
The greatest impact could be in sub-Saharan Africa and in vulnerable populations including intravenous drug users, sex workers, men who have sex with men, and children.
"Sub-Saharan Africa is home to a significant proportion of the global HIV burden, and has made great progress in reducing new HIV infections by more than 50% since 2010. The region is heavily reliant on international funding, particularly from PEPFAR. The study found that without mitigation, discontinuation of PEPFAR support could result in 10 million additional infections and almost 3 million deaths by 2030, undoing decades of progress in the region," ten Brink explained.
"There is an urgent need for innovative, country-led financing strategies and an integration of HIV services into broader health systems; however, this can't happen overnight," co-author Nick Scott, PhD, also of the Burnet Institute, added.
"Long-term strategic planning is required for countries to transition from internationally supported to domestically financed programs," he said. "Our study highlights how important international collaboration and investment have been in maintaining progress against HIV."
Study limitations included the unpredictability of foreign aid funding and the possibility of increased mitigation efforts and increased domestic funding, the researchers said. The results may not be generalizable to all countries, and it's possible the real impacts of immediate and severe funding cuts were underestimated.
Disclosures
Country models used in this project were financially supported by the Gates Foundation, the Global Fund to Fight AIDS, Tuberculosis, and Malaria, UNAIDS, the World Bank, and World Health Organization.
ten Brink and colleagues reported no disclosures.
Sibanda and Phillips also reported no disclosures.
Primary Source
The Lancet HIV
Source Reference: ten Brink D, et al "Impact of an international HIV funding crisis on HIV infections and mortality in low-income and middle-income countries: a modelling study" Lancet HIV 2025; DOI: 10.1016/ S2352-3018(25)00074-8.
Secondary Source
The Lancet HIV
Source Reference: Sibanda EL, Phillips AN "Modelling study shows staggering impact of HIV funding cuts" Lancet HIV 2025; DOI: 10.1016/ S2352-3018(25)00076-1.