Infants ages 6-11 months traveling to areas in the U.S. with measles outbreaks should follow the vaccination recommendations of the health department in their destination, federal officials said Tuesday.
The Centers for Disease Control and Prevention (CDC) updated its guidance as this year’s case count rose to 880, the highest since 1994 and since measles was declared eliminated in 2000.
“The United States remains in elimination, although the ongoing outbreaks in close-knit communities and increased global measles activity puts the U.S. at risk for losing elimination status,” Adria Lee, M.S.P.H., a member of the CDC’s measles epidemiology team, said during a CDC measles webinar Tuesday.
The median age of patients is 6 years. Rates are highest among children ages 12-15 months and 6-11 months.
The CDC and the Academy recommend children receive the first routine dose of measles, mumps and rubella (MMR) vaccine at 12-15 months and the second dose at 4-6 years. One dose of MMR is about 93% effective, and two doses are about 97% effective.
In outbreak settings with community-wide transmission in which infants are affected, health departments may recommend vaccinating 6- to 11-month-olds, but it would not count toward the two-dose series. The CDC updated its Manual for the Surveillance of Vaccine-Preventable Diseases to clarify that infants living in and traveling to these areas should follow the advice of the health department in the outbreak area.
“Benefit of early protection against measles during a period of increased transmission and exposure should be carefully weighed against the potential risk of decreased immune responses following subsequent doses of MMR in infants less than a year,” said Manisha Patel, M.D., M.S., measles surveillance team lead for the CDC.
Health departments in outbreak areas also may recommend a second dose of MMR at least 28 days after the first for children ages 1 through 4 years who are living in or visiting the area.
If children are traveling abroad, infants ages 6 months through 11 months should have one dose of MMR, and those 12 months and older should receive two doses at least 28 days apart, according to the CDC. About 6% of this year’s cases were internationally imported, most commonly from the Philippines, Ukraine and Israel.
Measles has symptoms like fever, cough, runny nose and watery eyes followed by a rash. It can result in complications like pneumonia, brain damage and deafness and can be fatal. This year, 9% of people with measles have been hospitalized.
About 90% of this year’s cases were unvaccinated, and 94% occurred in outbreak areas, according to Lee. Outbreaks are ongoing in Rock Island County, New York; New York City; Michigan; Georgia; Maryland; Pennsylvania; Washington and three California counties — Butte, Los Angeles and Sacramento.
Cases have been reported in 24 states — Arizona, California, Colorado, Connecticut, Florida, Georgia, Illinois, Indiana, Iowa, Kentucky, Maryland, Massachusetts, Michigan, Missouri, Nevada, New Hampshire, New Jersey, New York, Oklahoma, Oregon, Pennsylvania, Tennessee, Texas and Washington.