The Centers for Disease Control and Prevention (CDC) is urging Americans to make sure they’re protected against measles before traveling overseas this summer.
People who aren’t fully vaccinated — including individuals who can’t get the vaccine due to specific health reasons — should avoid international travel, the CDC recommends.
“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 said in the statement. “Infected travelers can bring the disease back to their home communities where it can spread rapidly among people who are not immune.”
Air Travel Is Especially Risky When It Comes to Measles
Airplanes pose a particular risk, especially on long international flights, says George Rutherford, MD, a professor emeritus at the University of California San Francisco who studies the prevention of infectious diseases.
“Measles risk is clearly higher on aircraft because of the closed space and air rebreathing,” Dr. Rutherford says.
Getting through the airport also poses an exposure risk, says Peter Hotez MD, PhD, a professor and co-director of the Texas Children’s Hospital Center for Vaccine Development and dean of the National School of Tropical Medicine at Baylor College of Medicine in Houston.
“Measles is a hardy respiratory virus and can stay suspended in the air for up to two hours or more,” Dr. Hotez says. “Potentially, this could include crowded air spaces such as airports or planes, themselves.”
Vaccination Is the Best Protection
While newborns can’t yet get the measles-mumps-rubella (MMR) vaccine, the CDC said infants 6 to 11 months old should get one dose of this vaccine before international travel.
Anyone 12 months or older should have two doses of the vaccine at least 28 days apart before an international trip, the CDC said, unless they have immunity for one of the following reasons:
- Written documentation of previous vaccination
- Lab test showing evidence of immunity
- Lab test confirmation of measles infection
- Birth in the United States before 1957
Infants who do get a dose of the measles vaccine before their first birthday will still need two more doses, one at between 12 and 15 months and another 28 days later, the CDC said.
Some Vaccinated People May Need Booster Shots
People born before 1957 shouldn’t need booster shots because nearly everyone that old got measles during childhood, before the first vaccine was approved (in 1963), according to Yale.
But there are other adults who may need a booster:
The modern MMW vaccine is what’s known as a live vaccine, meaning it contains a small, weakened dose of the virus, according to Yale. This trains a healthy immune system to recognize the measles, mumps, or rubella viruses if one tries to invade the body, and attack it, preventing infection.
People Vaccinated Between 1968 and 1989 These individuals got the newer live vaccine, but may still need a booster shot because it was common to get only a single dose during that period, per Yale.
People Who Are Unsure About Their Vaccination Status Anyone who isn’t sure when they were vaccinated, which type of vaccine they got, or how many doses they got may want to consider a booster shot now, according to Yale.
Who Is at Highest Risk of Measles?
“The unvaccinated remain at the highest risk of acquiring measles,” Hotez says. “This includes infants not old enough to receive their first MMR vaccine dose.”
What About Wearing a Mask on a Plane?
Masks can help reduce measles risk during international travel but they’re not foolproof, Rutherford says. “Vaccination is far and away the best preventive measure,” Rutherford says. “Do not lose sight of that”
If you choose to wear a mask for added protection, you should choose a N95 or KN95 mask, Hotez advises.
“A N95 or KN95 tight-fitting mask during air travel could reduce the likelihood of acquiring measles as well as other respiratory pathogens, and hand washing is always a good idea, too,” Hotez says. “But keeping up with your MMR immunizations remains the most effective means to prevent measles.”
