U.S. health authorities have revised their travel guidance on measles, now recommending that all Americans traveling abroad be vaccinated against the virus, regardless of where they’re headed.
While measles-mumps-rubella (MMR) vaccination is already advised for U.S. residents, the Centers for Disease Control and Prevention (CDC) had previously focused on immunization primarily for those traveling to countries with active outbreaks. That changed last week when the CDC broadened its recommendation to cover all international travel destinations.
Ashley Darcy-Mahoney, a professor and researcher at George Washington University’s School of Nursing, described the change as a major update. She highlighted a recent measles outbreak in Colorado that began with a passenger arriving on an international flight to Denver. The revised travel advisory, she said, acknowledges the increasing risk of exposure not just in outbreak zones, but also during the journey itself—including on airplanes and in airports.
“We’re seeing a shift from localized outbreaks to transmission happening during transit,” Darcy-Mahoney explained, noting that the CDC appears to be responding to this evolving risk.
Under the updated guidance, the CDC recommends two MMR vaccine doses for everyone in the U.S. aged 1 and older. For infants aged 6 to 11 months who are traveling internationally, one early dose is advised.
So far this year, the U.S. has recorded over 1,000 cases of measles, highlighting the importance of vaccination amid rising concerns about global travel-related transmission.