The Centers for Disease Control and Prevention issued an alert Thursday warning of a rise in measles cases.

The CDC alert warned health providers about several outbreaks, mainly among unvaccinated children.

This comes as vaccination rates have drop across the U.S. A CDC report says the U.S. reached a record number of vaccine exemptions in schools last year.

Cases have surged across the word, according to the World Health Organization. There were 9 million documented cases of measles in 2022.