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.

A child who wasn’t vaccinated died in a measles outbreak in rural West Texas, officials there said Wednesday, the first U.S. death from the highly contagious respiratory disease since 2015.

Covenant Children's Hospital in Lubbock, Texas, has confirmed the first death in the state from measles occurred at its facilities. Here is what we know.