Cuts to foreign aid could result in millions of HIV deaths and soaring rates of global infections, modeling study finds

A new modeling study published in The Lancet HIV journal highlights the alarming potential impact of significant reductions in international funding for HIV prevention and treatment programs.

The research estimates that, globally, between 4.4 to 10.8 million additional new HIV infections and 770,000 to 2.9 million HIV-related deaths in children and adults could occur between 2025 and 2030 if funding cuts proposed by the top five donor countries, including the U.S. and the UK, are not mitigated.

The most affected populations will likely be in sub-Saharan Africa, and marginalized groups who are already at a higher risk of acquiring HIV, such as people who inject drugs, sex workers, and men who have sex with men, as well as children.

Since 2015, international donors have contributed approximately 40% of all HIV funding in low-and-middle-income countries (LMICs), making their support crucial to global efforts to treat and prevent HIV. The U.S., UK, France, Germany, and the Netherlands together account for over 90% of international funding.

However, these countries have all recently announced plans to implement significant cuts to foreign aid, leading to a projected 24% reduction in global international HIV funding by 2026. In addition, the U.S. government, which is the largest contributor to foreign aid, providing nearly 73% of support, paused all foreign aid funding (with limited exceptions) on 20 January 2025 to allow for a 90-day review and evaluation.

Foreign aid programs, such as the US President’s Emergency Plan for AIDS Relief (PEPFAR), provide HIV treatment and prevention services, including funding health clinics that supply antiretroviral therapy (ART) to treat HIV and prevent its spread, HIV testing, and necessary laboratory services.

These programs also provide health services that go beyond HIV treatment and prevention and can include health systems strengthening, health care worker training, and combining HIV services with other health services, including tuberculosis treatment and prevention, and maternal and child health programs to improve overall health outcomes.

“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,” said co-lead study author Dr. Debra ten Brink of the Burnet Institute (Australia).

“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.”

To understand the potential impact of foreign aid funding reductions, the authors used a 26-country mathematical model, to estimate the effects of anticipated international aid reductions, including the immediate cessation of support from PEPFAR in all countries currently dependent on foreign aid to support programs to diagnose and prevent HIV.

When extrapolating across all LMICs, if funding reductions continue as planned, they found there could be between 4.4 million to 10.8 million additional new HIV infections by 2030, representing a 1.3 to 6-fold increase in new infections for people at higher risk of acquiring to HIV, compared to if funding levels remained consistent. These cuts could also cause between 770,000 to 2.9 million HIV-related deaths in children and adults by 2030.

“There could be an even greater impact in sub-Saharan Africa, where broader prevention efforts, such as distributing condoms and offering pre-exposure prophylaxis (PrEP—a medication that reduces the risk of getting HIV) are at first risk to be discontinued,” added co-lead study author Dr. Rowan Martin-Hughes of the Burnet Institute (Australia).

“This is in addition to disruptions in testing and treatment programs that could cause a surge in new HIV infections, especially in some of the areas where the greatest gains have been made, such as preventing mother-to-child transmission of HIV and pediatric HIV deaths.”

From 2010 to 2023, many countries that currently receive PEPFAR or other foreign aid support have made significant progress in treating and preventing HIV, with an average 8.3% yearly decrease in new infections and a 10.3% decrease in HIV-related deaths. If this trend continues, many countries would be on track to meet global targets to eliminate HIV/AIDS as a public health threat by around 2036.

However, by 2026, if foreign aid is greatly reduced or if PEPFAR funding is ceased entirely without an equivalent replacement, new infections, and deaths could rise back to levels not seen since 2010 and potentially undo all progress made since 2000.

Even if support for HIV treatment is restored after 12 to 24 months, the study suggests that the number of new HIV infections could stabilize at levels similar to those seen in 2020, which the authors note still represents a setback that could require an additional 20 to 30 years of investment to end HIV/AIDS as a public health threat.

“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. Long-term strategic planning is required for countries to transition from internationally supported to domestically financed programs. Our study highlights how important international collaboration and investment have been in maintaining progress against HIV,” said study author Dr. Nick Scott of the Burnet Institute (Australia).

The authors note some important limitations to their study, including that the foreign aid funding space is unpredictable, and it is unknown whether reductions in international aid will continue to escalate, how PEPFAR will continue, or whether a variety of mitigation efforts and more domestic financing will be introduced. Additionally, the analysis was performed for 26 countries and then extrapolated to all LMICs; therefore, it may not be fully representative of all regions or of all PEPFAR-funded countries.

Finally, the authors note that these results are likely an underestimate of the real impacts of immediate and severe funding cuts to HIV programs globally, especially in the sub-Saharan African region where disruptions to the supply chain, health workforce, and overall health systems could result in much broader health impacts beyond HIV. The wide range in the estimates reflects these various uncertainties.

Future research, including optimization of reduced budgets, could inform countries as to which HIV prevention, testing, and treatment interventions should be prioritized for maximum impact.

A new modeling study published in The Lancet HIV journal highlights the alarming potential impact of significant reductions in international funding for HIV prevention and treatment programs.

The research estimates that, globally, between 4.4 to 10.8 million additional new HIV infections and 770,000 to 2.9 million HIV-related deaths in children and adults could occur between 2025 and 2030 if funding cuts proposed by the top five donor countries, including the U.S. and the UK, are not mitigated.

The most affected populations will likely be in sub-Saharan Africa, and marginalized groups who are already at a higher risk of acquiring HIV, such as people who inject drugs, sex workers, and men who have sex with men, as well as children.

Since 2015, international donors have contributed approximately 40% of all HIV funding in low-and-middle-income countries (LMICs), making their support crucial to global efforts to treat and prevent HIV. The U.S., UK, France, Germany, and the Netherlands together account for over 90% of international funding.

However, these countries have all recently announced plans to implement significant cuts to foreign aid, leading to a projected 24% reduction in global international HIV funding by 2026. In addition, the U.S. government, which is the largest contributor to foreign aid, providing nearly 73% of support, paused all foreign aid funding (with limited exceptions) on 20 January 2025 to allow for a 90-day review and evaluation.

Foreign aid programs, such as the US President’s Emergency Plan for AIDS Relief (PEPFAR), provide HIV treatment and prevention services, including funding health clinics that supply antiretroviral therapy (ART) to treat HIV and prevent its spread, HIV testing, and necessary laboratory services.

These programs also provide health services that go beyond HIV treatment and prevention and can include health systems strengthening, health care worker training, and combining HIV services with other health services, including tuberculosis treatment and prevention, and maternal and child health programs to improve overall health outcomes.

“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,” said co-lead study author Dr. Debra ten Brink of the Burnet Institute (Australia).

“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.”

To understand the potential impact of foreign aid funding reductions, the authors used a 26-country mathematical model, to estimate the effects of anticipated international aid reductions, including the immediate cessation of support from PEPFAR in all countries currently dependent on foreign aid to support programs to diagnose and prevent HIV.

When extrapolating across all LMICs, if funding reductions continue as planned, they found there could be between 4.4 million to 10.8 million additional new HIV infections by 2030, representing a 1.3 to 6-fold increase in new infections for people at higher risk of acquiring to HIV, compared to if funding levels remained consistent. These cuts could also cause between 770,000 to 2.9 million HIV-related deaths in children and adults by 2030.

“There could be an even greater impact in sub-Saharan Africa, where broader prevention efforts, such as distributing condoms and offering pre-exposure prophylaxis (PrEP—a medication that reduces the risk of getting HIV) are at first risk to be discontinued,” added co-lead study author Dr. Rowan Martin-Hughes of the Burnet Institute (Australia).

“This is in addition to disruptions in testing and treatment programs that could cause a surge in new HIV infections, especially in some of the areas where the greatest gains have been made, such as preventing mother-to-child transmission of HIV and pediatric HIV deaths.”

From 2010 to 2023, many countries that currently receive PEPFAR or other foreign aid support have made significant progress in treating and preventing HIV, with an average 8.3% yearly decrease in new infections and a 10.3% decrease in HIV-related deaths. If this trend continues, many countries would be on track to meet global targets to eliminate HIV/AIDS as a public health threat by around 2036.

However, by 2026, if foreign aid is greatly reduced or if PEPFAR funding is ceased entirely without an equivalent replacement, new infections, and deaths could rise back to levels not seen since 2010 and potentially undo all progress made since 2000.

Even if support for HIV treatment is restored after 12 to 24 months, the study suggests that the number of new HIV infections could stabilize at levels similar to those seen in 2020, which the authors note still represents a setback that could require an additional 20 to 30 years of investment to end HIV/AIDS as a public health threat.

“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. Long-term strategic planning is required for countries to transition from internationally supported to domestically financed programs. Our study highlights how important international collaboration and investment have been in maintaining progress against HIV,” said study author Dr. Nick Scott of the Burnet Institute (Australia).

The authors note some important limitations to their study, including that the foreign aid funding space is unpredictable, and it is unknown whether reductions in international aid will continue to escalate, how PEPFAR will continue, or whether a variety of mitigation efforts and more domestic financing will be introduced. Additionally, the analysis was performed for 26 countries and then extrapolated to all LMICs; therefore, it may not be fully representative of all regions or of all PEPFAR-funded countries.

Finally, the authors note that these results are likely an underestimate of the real impacts of immediate and severe funding cuts to HIV programs globally, especially in the sub-Saharan African region where disruptions to the supply chain, health workforce, and overall health systems could result in much broader health impacts beyond HIV. The wide range in the estimates reflects these various uncertainties.

Future research, including optimization of reduced budgets, could inform countries as to which HIV prevention, testing, and treatment interventions should be prioritized for maximum impact.