Kansas health officials have confirmed 23 measles cases, marking an outbreak for the state as infections in at least 17 states have led to the most cases in the U.S. in a single year since 2019. The Kansas outbreak is spread across 6 southwest counties, the state's Department of Health and Environment said Wednesday.

Kansas and Ohio health officials have confirmed several measles cases among mostly unvaccinated children and adults, as the total number of states reporting measles outbreaks reaches 18.

A measles outbreak in Kansas has more than doubled to nearly two dozen cases over the last week, according to state health officials, who said they identified a “possible link” between confirmed cases of the highly contagious illness and a larger outbreak in Texas and New Mexico.