Cutting the budget of the President's Malaria Initiative (PMI) by 44%, as the U.S. Congress has proposed, would lead to an estimated 67 million additional cases of malaria over the next four years, according to a mathematical model published this week in PLOS Medicine by Peter Winskill of Imperial College London, UK, and colleagues.

The PMI, established in 2005 and funded by the US Agency for International Development (USAID), has provided ongoing support to malaria control programs in 19 African countries and is the largest bilateral funder of malaria prevention and treatment. In May 2017, Congress published a budget justification document which included a 44% proposed reduction to PMI funding for 2018. In the new study, the researchers inputted data on PMI funding and epidemiology into an established model of Plasmodium falciparum malaria to project the impact of reductions in funding.

If funding is maintained, PMI-funded interventions are estimated to avert 162 million more cases (95% CrI: 116 million, 194 million) of malaria and save 692,589 (95% CrI: 392,694, 955,653) lives between 2017 and 2020 compared to no PMI support. If a 44% reduction in funding occurs, the model revealed that this loss of direct aid could result in an additional 67 million (95% CrI: 49 million, 82 million) cases of malaria and 290,649 deaths (95% CrI: 167,208, 395,263) between 2017 and 2020 compared to maintaining current levels of funding.

"Our results provide a conservative estimate of the overall impact of PMI funding as we do not capture the impact of all PMI-associated activities," the authors say. "PMI's ongoing support... in counties of high burden or strategic importance is vital in order to avoid a rapid erosion of the progress made in the last 15 years on the road towards malaria eradication."