Evaluating the impact of two decades of USAID interventions and projecting the effects of defunding on mortality up to 2030: a retrospective impact evaluation and forecasting analysis.

backgroundThe US Agency for International Development (USAID) is the largest funding agency for humanitarian and development aid worldwide. The aim of this study is to comprehensively evaluate the effect of all USAID funding on adult and child mortality over the past two decades and forecast the future effect of its defunding.

methodsIn this retrospective impact evaluation integrated with forecasting analysis, we used panel data from 133 countries and territories- including all low-income and middle-income countries (LMICs)-with USAID support ranging from none to very high. First, we used fixed-effects multivariable Poisson models with robust SEs adjusted for demographic, socioeconomic, and health-care factors to estimate the impact of USAID funding on all-age and all-cause mortality from 2001 to 2021. Second, we evaluated its effects by age-specific, sex-specific, and cause-specific groups. Third, we did several sensitivity and triangulation analyses. Lastly, we integrated the retrospective evaluation with validated dynamic microsimulation models to estimate effects up to 2030.

findingsHigher levels of USAID funding-primarily directed toward LMICs, particularly African countries-were associated with a 15% reduction in age-standardised all-cause mortality (risk ratio [RR] 0·85, 95% CI 0·78-0·93) and a 32% reduction in under-five mortality (RR 0·68, 0·57-0·80). This finding indicates that 91 839 663 (95% CI 85 690 135-98 291 626) all-age deaths, including 30 391 980 (26 023 132-35 482 636) in children younger than 5 years, were prevented by USAID funding over the 21-year study period. USAID funding was associated with a 65% reduction (RR 0·35, 0·29-0·42) in mortality from HIV/AIDS (representing 25·5 million deaths), 51% (RR 0·49, 0·39-0·61) from malaria (8·0 million deaths), and 50% (RR 0·50, 0·40-0·62) from neglected tropical diseases (8·9 million deaths). Significant decreases were also observed in mortality from tuberculosis, nutritional deficiencies, diarrhoeal diseases, lower respiratory infections, and maternal and perinatal conditions. Forecasting models predicted that the current steep funding cuts could result in more than 14 051 750 (uncertainty interval 8 475 990-19 662 191) additional all-age deaths, including 4 537 157 (3 124 796-5 910 791) in children younger than age 5 years, by 2030.

interpretationUSAID funding has significantly contributed to the reduction in adult and child mortality across low-income and middle-income countries over the past two decades. Our estimates show that, unless the abrupt funding cuts announced and implemented in the first half of 2025 are reversed, a staggering number of avoidable deaths could occur by 2030.

fundingThe Spanish Ministry of Science and Innovation, UK Medical Research Council, and EU Horizon Europe.