As of March 27, the United States issues report 483 confirmed measles cases and two deaths. The Centers for Disease Control and Prevention (CDC) has already identified three major outbreaks in 2025. With cases increasing, the World Health Organization (WHO) has issued a travel advisory, urging travelers to ensure their measles vaccinations are up to date before visiting the US.
WHO advised international travelers to verify their immunization status before departure, particularly if traveling to affected areas in the US. The agency also recommended that unvaccinated individuals exposed to measles or showing symptoms consult local health authorities before traveling abroad. However, warning issues stated that no additional travel restrictions are necessary at this time.
To manage the spread of imported cases, WHO emphasized the importance of maintaining vaccine stockpiles, including measles-rubella (MR) and MMR vaccines, along with syringes and other supplies. It also stressed the need for vaccination services for international travelers, particularly those traveling to outbreak-affected regions, displaced populations, and other vulnerable groups.
The outbreak has spread across 20 US jurisdictions, including Alaska, California, Florida, Georgia, Kansas, Kentucky, Maryland, Michigan, Minnesota, New Jersey, New Mexico, New York City, New York State, Ohio, Pennsylvania, Rhode Island, Tennessee, Texas, Vermont, and Washington. Texas remains the hardest-hit state, with 400 reported cases as of March 28.
The CDC has highlighted international travel as a key factor in measles transmission. “Unvaccinated individuals traveling abroad bring the disease into the United States,” the agency stated, noting that two-thirds of these travelers are American. Upon their return, they risk spreading measles to others who are not immunized, potentially triggering outbreaks.
