Measles cases in the United States are the highest they’ve been since the country eliminated the disease in 2000. The U.S. has reported 1,277 cases since the start of the year, according to NBC News’ tally of state health department data.

The University of Texas and Austin Public Health created a measles simulator for school districts and private schools around the county to better understand their risks.

U.S. measles cases hit 1,277—the worst outbreak since the disease was declared eliminated in 2000, surpassing 2019's peak.

The Centers for Disease Control and Prevention says the U.S. is currently experiencing its worst measles outbreak in more than 30 years, according to the Associated Press. On Wednesday, the CDC said the 2025 case count has surpassed the 2019 count, when there were 1,274 cases for the year.

While measles symptoms typically resolve in a few weeks, the virus can cause pneumonia, making it difficult for patients, especially children, to get oxygen into their lungs. It may also lead to brain swelling, which can cause lasting damage, including blindness, deafness and intellectual disabilities.

The U.S. is having its worst year for measles spread in more than three decades, with a total of 1,288 cases nationally and another six months to go in 2025.