Los Angeles County health officials have issued a public health alert after someone with an infectious case of measles visited Universal Studios Hollywood last month, potentially exposing numerous park-goers to the highly contagious virus.

The Los Angeles County Department of Public Health confirmed that anyone present at the theme park on Sunday, July 26, between 10 a.m. and 9 p.m., may have been exposed.

Officials are currently investigating other potential exposure sites. Individuals who visited during this timeframe are advised to monitor themselves for symptoms until August 16.

While those who have previously contracted measles or received the recommended measles-mumps-rubella (MMR) vaccine are generally protected, health officials still recommend vigilance for symptoms. Unvaccinated individuals or those with an unknown vaccination status face a significantly higher risk of infection.

“As measles cases increase, it is important that residents take steps to make sure they are fully protected,” Los Angeles County Health Officer Dr. Muntu Davis said in a statement. “The MMR vaccine is the safest and most reliable way to prevent measles and protect yourself, your family and your community.”

Health officials urged residents to review their vaccination records, particularly before traveling, and to contact a health care provider if they are pregnant, immunocompromised, have an infant younger than 12 months who may have been exposed or are otherwise at higher risk.

Anyone who develops symptoms including fever, cough, runny nose, red eyes or a rash should stay home, avoid school, work and public gatherings, and contact a health care provider before visiting a medical facility, officials said.

Measles spreads through the air when an infected person breathes, talks, coughs or sneezes, and the virus can remain in the air or on surfaces for several hours after the infected person has left an area. According to the department, two doses of the MMR vaccine are about 97 percent effective at preventing the disease.

As of July 31, 2,371 measles cases have been reported nationwide this year, according to county health officials. Most of the cases are linked to outbreaks that began in 2025 and 2026. Los Angeles County last reported a measles case on July 21.