Measles has been spreading in the U.S. for a year, a milestone that could mean the virus can no longer be considered eliminated.

A growing measles outbreak in South Carolina has infected more than 600 people since October, with hundreds more being potentially exposed.

Tuesday marks one year since a measles outbreak started in West Texas, and there have been more new cases in the United States each week since.

The U.S. has held its measles-free status for more than 25 years. Experts say unrelenting outbreaks in the past year may change that

Just one year after the worst measles outbreak in the country began in West Texas, public health officials said the U.S. could lose its measles elimination status. Public health leaders from North Texas and Lubbock warn declining vaccination rates could increase risk of future measles outbreaks.

It’s unclear whether the United States can keep its designation as a country that officially eliminated the disease.

Wisconsin played a part in that, with a measles outbreak in Oconto County that stretched from August to October. The U.S. is on the verge of losing its measles-free status because of ongoing transmission. The decision will come in spring.

After a year of ongoing measles outbreaks that have sickened more than 2,400 people, the United States is poised to lose its status as a measles-free country.

Without citing evidence, Ken Paxton, said he is targeting a purported system that illegally incentivizes providers to recommend vaccines that are "not proven to be safe or necessary."

South Carolina reports over 500 measles cases, the largest US outbreak in 2026, with Spartanburg County most affected and hundreds quarantined.