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.

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

With nearly six months left in the year, the total number of cases so far in 2025 has surpassed every year since 1992