Health officials have confirmed measles exposure incidents at two major airports, Hollywood Burbank Airport in California and Chicago O'Hare International Airport, as the United States experiences a significant increase in measles cases nationwide. Thousands of travelers may have been exposed to the highly infectious disease.
In the Los Angeles area, a traveler confirmed to have measles was present on Southwest Airlines Flight 4245, which arrived at Hollywood Burbank Airport on June 17. Passengers at Gate A4 between 8:45 a.m. and 9:45 a.m. that day may have been exposed. Further potential exposure occurred at Thrifty Rental Car Service at 2627 N. Hollywood Way in Burbank between 9:20 a.m. and 10:20 a.m. on June 17, and again from 10:25 a.m. to 11:25 a.m. on June 18.
Separately, the Chicago Department of Public Health reported that an international traveler confirmed with measles was at Chicago O'Hare International Airport on June 17. Individuals in Terminal 5 between 5:50 a.m. and 9:30 a.m. on that date may have been exposed. No details about the infected travelers, including their vaccination status or origin, have been released.
These airport alerts come as the U.S. grapples with a nationwide measles outbreak. This year, California has recorded 51 measles cases, and Illinois has reported fewer than 10. According to CDC data, the U.S. has documented 2,104 measles cases in 41 states as of the week ending June 14, a more than threefold increase compared to the same period last year. In 2025, the U.S. registered 2,285 measles cases. While 131 patients have been hospitalized, no deaths have been reported this year, although three fatalities occurred in the previous year.
Health officials are actively working to identify and notify individuals who may have been exposed. They are also emphasizing the importance of the measles, mumps, and rubella (MMR) vaccine. According to Dr. Muntu Davis, Los Angeles County Health Officer, "The MMR vaccine is the safest and most reliable way to prevent measles and protect yourself, your family and your community." Two doses of the MMR vaccine are highly effective, reducing the risk of infection by 97 percent. For unvaccinated individuals, nine out of ten exposed to the virus are likely to become infected.
Measles is a highly contagious viral illness characterized by fever, cough, a distinctive blotchy rash that begins on the face and spreads, and small white spots inside the mouth known as Koplik spots. The virus spreads through direct contact with infectious droplets or airborne transmission. Infected individuals are contagious from four days before the rash appears through four days after. Enclosed spaces like airports and airplanes are considered high-risk environments for transmission.
While measles can sometimes cause milder symptoms such as diarrhea and sore throat, it can lead to serious complications. Approximately six percent of otherwise healthy children develop pneumonia, a rate that is higher in malnourished children. Brain swelling, or encephalitis, occurs in about one in 1,000 cases and can be fatal in 15-20 percent of those affected, with approximately 20 percent suffering permanent neurological damage. Measles also significantly weakens the immune system, increasing susceptibility to other infections.
Before the widespread availability of the MMR vaccine in the 1960s, measles caused annual epidemics resulting in millions of deaths globally. By 2023, global deaths had fallen to approximately 107,000. Nationwide, 92.5 percent of kindergarteners are vaccinated against measles, which is below the 95 percent threshold recommended by the CDC for herd immunity.