FILE - In this May 17, 2019, file photo, a measles vaccination is seen at the Knox County Health Department in Mount Vernon, Ohio. Sri Lanka and Maldives have become the first two countries in the World Health Organization's South-East Asia region to eliminate both measles and rubella ahead of a 2023 target, the U.N. health agency announced Wednesday. (AP Photo/Paul Vernon, File)

FILE - In this May 15, 2019, file photo, a dose of the measles, mumps and rubella vaccine is displayed at the Neighborcare Health clinics at Vashon Island High School in Vashon Island, Wash. Sri Lanka and Maldives have become the first two countries in the World Health Organization's South-East Asia region to eliminate both measles and rubella ahead of a 2023 target, the U.N. health agency announced Wednesday. (AP Photo/Elaine Thompson, File)