Since the start of 2025, several locations across North America have grappled with outbreaks of the infectious respiratory disease commonly known as measles.
Amid U.S. Health Secretary Robert F. Kennedy, Jr.’s anti-vaccine stance and rhetoric, and as more families choose to opt out of the MMR vaccine that for decades has been given to children during their first years of life, measles outbreaks are increasingly emerging in multiple parts of the country.
Last February, a six-year-old child unvaccinated against the airborne disease became the first recorded measles death in the U.S. since 2015. As of June 5, the Centers for Diseases Control and Prevention (CDC) recorded 1,168 confirmed measles cases in states including California, Florida, Georgia, Michigan, New Mexico, New York, Texas and Virginia.
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A measles outbreak has been traced to an international flight to Denver
The Western state of Colorado has seen a particularly large outbreak, with several cases stemming from a traveler coming in to Denver International Airport.
At least seven new cases in the state have been traced to an unvaccinated traveler who infected others on a Turkish Airlines flight arriving on May 14. After landing, the traveler was also found to have exposed visitors and staff at a local Trader Joe’s grocery store.
“Public health officials are notifying members of the public of additional areas for potential measles exposures, as a result of these confirmed cases,” the Colorado Department of Public Health and Environment advisory states. “The adults are unrelated, but were at Denver International Airport around the same time on Wednesday, May 14.”
Amid the outbreak in the state, the Centers for Diseases Control and Prevention (CDC) has also issued an advisory singling out the Denver Airport. As of June 5, the state has a total of 14 recorded measles cases.
Texas has by far the most with over 700 active cases, while New Mexico and Kansas each have more than 50.
Colorado is seeing one of the country’s largest measles outbreaks this spring.
Image source: Visions of America/Universal Images Group via Getty Images
‘Travelers can catch measles in many travel settings’
“Measles is an ongoing risk around the world, and more international travelers are getting infected,” the CDC advisory from May 28 reads. “Travelers can catch measles in many travel settings including travel hubs like airports and train stations, on public transportation like airplanes and trains, at tourist attractions, and at large, crowded events.”
More on travel:
New York is warning residents about domestic travelGovernment issues new travel advisory on popular beach destinationAnother country just issued a new visa requirement for visitors
A spokesperson for the CDC had previously told CBS that 62 of the measles cases recorded in 2025 could be traced to international travel, while both states and foreign nations have issued advisories about unvaccinated individuals traveling to areas where case numbers are high.
“All New Yorkers [are asked] to ensure they are fully vaccinated against measles before international travel or travel to an area in the U.S. experiencing an outbreak,” New York State Health Commissioner Dr. James McDonald said in a March 2025 statement. He reminded travelers that “in some cases measles is as close as a car ride away.”
“Before traveling, make sure you have your complete vaccination schedule,” Mexico’s health department said in a warning to its citizens. “[The] risk level of contracting measles is medium for people who go to Texas.”
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