In response to a significant resurgence of measles across the United States, the Centers for Disease Control and Prevention (CDC) has escalated its public health advisory. The warning focuses on air travel, following confirmed cases of transmission aboard commercial flights.
The alert comes as measles cases rise not only across the US but also in neighbouring countries such as Mexico and Canada. The situation has prompted updated guidance on vaccinations and travel behaviour as health authorities aim to curb further outbreaks.
Increased Transmission During Air Travel and Airport Exposure
The CDC has identified airports, airplanes, and other travel hubs as key points of exposure, reflecting the highly transmissible nature of the measles virus.
According to CDC data, 62 individuals reported to be contagious travelled by air within or into the US since the beginning of the year. After investigating 50 of these cases, officials confirmed in-flight transmission in at least one instance.
“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,” the CDC stated in its most recent update.
Several incidents have prompted public alerts, particularly after infectious individuals passed through major airports such as Newark, Chicago, Seattle, and Denver.
These exposures are more difficult to trace once passengers disperse. Local and state health departments are leading investigations, particularly as more infections are detected among domestic travellers. The CDC has dropped its list of high-risk countries, instead underlining a more general warning: measles remains “an ongoing risk around the world.”
Vaccination Guidance Updated Amid Largest Outbreak Since 2019
The number of confirmed measles cases in the United States has reached at least 1,088 so far this year, according to CDC data. This marks the largest outbreak since 2019. Around 90% of current cases are linked to domestic outbreaks, not international travel, with states such as Texas, Iowa, and Nebraska recently reporting new infections.
The agency has replaced its earlier recommendation that travellers “consider making alternative travel plans” if unvaccinated. It now advises people to “consider postponing their trip” altogether. In addition, new guidance encourages doctors to offer extra vaccinations to domestic travellers where appropriate.
Measles symptoms include rash, runny nose, and fever, but the virus can lead to serious complications such as lung infections, brain swelling (encephalitis), and death. Vulnerable populations—particularly young children and pregnant women—remain at the highest risk of severe outcomes.
