Public health officials in Los Angeles County are investigating a potential measles exposure after an infected individual spent 11 hours at Universal Studios Hollywood on July 26. The person visited the park from 10 a.m. to 9 p.m., potentially exposing other visitors to the highly contagious viral disease.

Authorities urged anyone who was at the amusement park on that day to verify their immunity to measles and monitor themselves for symptoms for up to 21 days following exposure, with the last day of potential symptom onset being August 16. Measles symptoms often begin with fever, cough, runny nose, and red, watery eyes, followed by a characteristic rash that typically starts on the face and spreads to the rest of the body within three to five days.

The Los Angeles County Public Health Department noted that measles can be transmitted through the air when an infected individual breathes, talks, coughs, or sneezes. The virus can linger in the air and on surfaces for several hours even after the infected person has left the area. Notably, individuals are contagious for up to four days before the rash appears and remain so for four days after the rash’s onset.

Health officials emphasized the importance of vaccination, recommending the MMR (measles, mumps, and rubella) vaccine as the most effective protection against the disease. The vaccine is administered in two doses and is considered highly effective in preventing measles and its complications.

The warning comes amid a rise in measles cases across California, with the number of cases having doubled compared to the previous year. The California Department of Public Health reported three localized outbreaks in 2026, all of which have since been contained.

Certain groups are at higher risk of severe illness from measles, including unvaccinated infants under 12 months, pregnant individuals, and those with weakened immune systems. These individuals are advised to contact their healthcare providers promptly if they visited Universal Studios on the specified date and begin to show symptoms. Health officials recommended that anyone who develops symptoms avoid public places such as schools, workplaces, and gatherings and contact a healthcare professional by phone before seeking in-person care, to prevent further spread.

Public health officer Muntu Davis highlighted the ongoing risks associated with increased travel and attendance at crowded events during the summer months, urging people to ensure they are protected against infectious diseases through vaccination.