The CDC says that even if travel is less than 2 weeks away, unvaccinated individuals should still receive a dose of the measles, mumps, and rubella vaccine for protection against the disease.
Cases of measles in the US often originate from international travel, with about 2 out of 3 unvaccinated people contracting the infection in other countries. Although the disease was considered to be eliminated in 2000, people can continue to bring it into the US if they are not vaccinated and are infected during travel.1,2
The CDC recommends that to be protected against measles, individuals should plan to be fully vaccinated for measles, mumps, and rubella (MMR) at least 2 weeks prior to departure. One dose of the MMR vaccine can provide approximately 93% protection, whereas 2 doses can provide 97% protection. Following international travel, the CDC urges individuals to monitor their health for 3 weeks after returning.1
Additionally, the CDC notes that infants who are younger than 12 months should get an early MMR dose at 6 through 11 months, with another dose at 12 through 15 months and a final dose between the ages of 4 and 6. For children older than 12 months and teenagers and adults with no evidence of immunity, the CDC recommends that they are vaccinated immediately and receive their second dose 28 days following the initial dose. Acceptable evidence of immunity against measles includes written documentation of adequate vaccination, laboratory evidence or confirmation of immunity or measles, or birth in the US before 1957.1
Children who are aged 5 years and younger, adults over the age of 20 years, pregnant women, and those who are immunocompromised are more likely to have complications from measles infection, such as diarrhea and vomiting, ear infection, pneumonia, pregnancy problems (eg, premature or babies with low birthweight), bronchitis, laryngitis, and croup.2
"Measles is a viral infection that is highly contagious if you're not immune to it," says Nipunie Rajapakse, MD, MPH, pediatric infectious diseases physician, Mayo Clinic Children's Center, in a news release. "It’s generally characterized by fever, cough, runny nose and a pretty characteristic rash that can involve much of the skin surface."2
A study with results published in Vaccines in April 2024 found that global measles cases continue to rise following disruptions in routine immunization programs during the COVID-19 pandemic. The disruptions have consequences, according to the authors. Factors contributing to the disruption of vaccination include behavioral and social drivers, such as how people think and feel about vaccines, social processes, motivation to vaccinate, and physical barriers to vaccination; however, the authors found that the drivers of measles vaccine uptake are not the same as those common for other childhood vaccines.3
"Measles is one of the most contagious infectious diseases out there. If you're in the same airspace as someone with measles, if they were there 2 hours ago and you're not immune to it, you can still contract measles, even without ever coming in face-to-face contact with that person,” explained Rajapakse in the news release. “That's why the vaccination is so important. It gives you baseline immunity.”2
The study authors recommend the following approaches to approve MMR vaccination uptake: health departments should invest in and encourage a learning health systems approach to collect data to inform decision-making as well as evidence-based care; the establishment of surveillance on the social and behavioral drivers of measles vaccine uptake over time; evidence-based interventions that target and address specific barriers; and the assessment of perceived vaccine accessibility, affordability, and availability, even in settings where vaccinations are free.3
"Measles used to be a relatively common childhood illness. Since we've introduced very effective immunization, measles is quite rare to see here in the US," said Rajapakse in the news release. "It can infect the brain, for example, resulting in something called encephalitis. It can cause severe pneumonia. We're trying to avoid these complications by vaccinating children before they get sick with it."2