Texas authorities on Wednesday announced the first measles death in the state's outbreak of the highly contagious disease. The death, of a school-age child, is the first measles death in the U.S. since 2015,

The effectiveness of the vaccine, coupled with rising vaccination rates, led to such low rates of measles that it was declared eliminated in the U.S. in 2000. In recent years, though, the virus has made a resurgence, as childhood vaccination rates have dropped nationwide.