CDC measles alert urges MMR vaccine for youngest international travelers

baby on a plane


Amid rising measles cases internationally and in the United States, the Centers for Disease Control and Prevention (CDC) today issued an alert to health providers urging them to ensure that children as young as 6 months old receive the measles, mumps, and rubella (MMR) vaccine before traveling internationally.

In its latest weekly update, the CDC reported 13 more measles cases from 17 jurisdictions, raising the total so far this year to 58. The number of 2024 cases so far now equals the number reported for all of 2023.

Most US cases linked to international travel

In its Health Alert Network notice, 54 of 58 cases this year have links to international travel, the CDC said, which most of them involving children ages 12 months and older who hadn't received MMR vaccination. "Many countries, including travel destinations such as Austria, the Philippines, Romania, and the United Kingdom, are experiencing measles outbreaks," the CDC said.

Typically, children in the United States receive their first MMR dose at 12 to 15 months, with a second dose given at 4 through 6 years of age. The CDC said, however, that children ages 6 to 11 months who are traveling internationally should receive one MMR dose before departure, with two more doses given when they are 12 to 15 months old.

The CDC recommends that all travelers who don't have evidence of immunity to measles—no matter what age—be vaccinated before traveling internationally.

Declining coverage in US kindergarteners

Earlier this year the CDC warned of a global rise in case due to gaps in vaccination coverage, and today it provided more details about gaps in US coverage.

The MMR vaccine is thought to provide herd immunity when more than 95% of people in a community are vaccinated. However, vaccination coverage in kindergarteners declined from 95.2% in the 2019-20 school year to 93.1% in the 2022-23 school year, putting 250,000 kindergarteners at risk of contracting the virus each year over the past 3 years.

Thirty-six states and the District of Columbia had vaccination rates below 95% during the last school year, and, of those states, 5% of kindergarteners had medical or nonmedical exemptions.

Because most US communities have high population immunity, the risk of widespread measles transmission is low, though pockets of low coverage leave some locations at higher risk of outbreaks. A good portion of US cases this year came from an ongoing outbreak at a migrant shelter in Chicago and at an elementary school in Broward County, Florida.

Ohio reports 2nd case in Montgomery County

In related developments, Ohio health officials on March 15 announced a second case in Montgomery County and warned of potential exposures at a Disney on Ice performance in Cincinnati on March 8.

Dayton and Montgomery Public Health also warned of potential exposure at a health center in Dayton on March 13.

The county reported its first case in the middle of February, which involved a Miami County resident who may have exposed people at a grocery store in Englewood, which is in Montgomery County.

This week's top reads