The freeze on U.S. foreign aid ordered by President Donald Trump has effectively halted one of the world's most successful responses to a disease.

Zimbabwe: Florence Makumene clutched a plastic container of HIV medication, fearing it could be her last. The 53-year-old Zimbabwean, who tested positive in 2016, has survived thanks to the U.S.-funded President’s Emergency Plan for AIDS Relief (PEPFAR).

South African lab technician Nozipho Mlotshwa was waiting for the test results for a potential HIV vaccine, which has eluded scientists for decades, when the order came from USAID to stop work.