On Oct. 1, 2026, the U.S. is enduring its worst year for measles since 1991. Since the beginning of last year, large outbreaks have been reported in several states, including Texas, Utah, South Carolina and, now, Pennsylvania.

The year’s cases have come in waves, with one earlier this year and another as summer
turned to fall. as of Oct. 1 the U.S. Centers for Disease Control and Prevention has reported 3,887 confirmed cases of the measles.

Measles cases have been reported across the country. Pennsylvania, South Carolina and Utah have seen the most. Only five states haven’t reported any cases.

Measles was declared eliminated in the United States in 2000, meaning the disease was no longer continuously spreading in the country. For years, the U.S. saw relatively few cases. Now, pockets of unvaccinated residents are allowing outbreaks – defined as three or more related cases – to spring up.

Children and teenagers account for most confirmed cases. The overwhelming majority of people who have contracted measles were either unvaccinated or had an unknown vaccination status. Public health officials agree that the best way to protect yourself from measles is getting a vaccine.