At least 153 students from two schools in Spartanburg County, South Carolina, are under a 21-day quarantine due to potential exposure to measles, according to state health officials. The students affected were not vaccinated against the disease.

The schools involved are Global Academy of South Carolina and Fairforest Elementary. This outbreak has resulted in at least eight confirmed cases of measles, contributing to a total of 11 cases reported in South Carolina this year.

Nationwide, the United States has seen at least 1,563 measles cases in 2023, marking the highest number since 1992, according to the latest data from the Centers for Disease Control and Prevention. This year has also recorded 44 measles outbreaks, a significant increase from the 16 outbreaks reported in the previous year.

The rise in measles cases coincides with a decline in vaccination rates for the measles, mumps, and rubella (MMR) vaccine across the country. Prior to the COVID-19 pandemic, over 95% of kindergarteners received the MMR vaccine. However, that percentage has dropped to 92.5% in the most recent school year. This decline has left an estimated 286,000 kindergarteners without adequate protection against measles.