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

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.

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

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

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

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. However, the newly appointed principal deputy director at the Centers for Disease Control and Prevention,

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.