Former President Bill Clinton joined United Nations officials Thursday to formally open an online effort to enlist American air travelers in an effort to fight diseases in the developing world, the Associated Press reports.

Through the MassiveGood program, travelers can donate $2 or more when buying flight tickets online. Several major ticket distributors and sellers such as Travelocity will offer the giving option, but it will not be available directly from an airline’s Web site.

The money will be used to supply low-cost HIV/AIDS, malaria, and tuberculosis medications and improve maternal and children’s health. It will be administered by the Millennium Foundation, which raises money for U.N. health programs, and Unitaid, a World Health Organization-affiliated entity for purchasing drugs.