President Donald Trump's abrupt withdrawal from the World Health Organization and subsequent cuts to global health programs have created a public health emergency threatening millions of lives. The sudden halt to over $120bn in PEPFAR funding forced closure of HIV treatment services, with UN agencies projecting six million HIV-related deaths by 2030.

These policy changes represent an "extraordinary event" under International Health Regulations, constituting a public health risk through potential international disease spread. While measles has already crossed from the US to Mexico, the full impact remains as programs dependent on US funding shut down worldwide.

A PHEIC determination by WHO could prevent further erosion of global health cooperation despite other wealthy countries also cutting development assistance. The US government's claim of WHO withdrawal faces legal questions as membership fees remain unpaid, leaving the future of international health security in limbo.