MIAMI — Two recent outbreaks of measles in the United States highlight the need for vaccination and vigilance for infections imported from overseas, including Europe.
“We need to be aware of the importations from Europe,” said Dr. Carol J. Baker. “Most people do not think of MMR as a travel vaccine. There is a lot of measles in Europe now.”
The Centers for Disease Control and Prevention reported both outbreaks in February 2008.
In one instance, 11 cases in San Diego County in January and February of this year were linked to a 7-year-old unvaccinated boy who was infected during a family trip to Switzerland (MMWR 2008;57:203-6).
None of the eight children he subsequently infected was vaccinated, including two siblings, two playmates from school, and four children exposed in a pediatrician's office (three were infants younger than the immunization age). Another three students at the school were secondarily infected.
About 10% of the children at his school, including those infected, were vaccine personal belief exemptors.
“If you have more and more vaccine exemptors, you will be, as a community, more susceptible to measles,” Dr. Baker said during a pediatric update sponsored by Miami Children's Hospital.
No vaccinated child exposed to the San Diego index case became infected.
Suspect measles infection for all patients who have traveled overseas and present with a fever and rash, Dr. Baker advised. In addition, “separate a suspected case from the waiting room…clean the room very well and wait a few hours [before reentering].”
An earlier outbreak of measles in August and September 2007 also was imported and associated with an unvaccinated youth. The index case was a 12-year-old boy from Japan who attended an International Youth event in Pennsylvania (MMWR 2008;57:169-73).
A multistate investigation identified seven additional measles infections in Pennsylvania, Michigan, and Texas, including six confirmed from the index case using genetic sequencing.
Estimated attendance at the event was 265,000 and included teams from Canada, Chinese Taipei, Curaçao, the Netherlands, Venezuela, Mexico, Saudi Arabia, and Japan. The coaches and boys, who were aged 10-13 years, were housed in the same compound during the event, according to the CDC report.
“If you hear one of your patients is going to one of these events, make sure they are vaccinated,” said Dr. Baker, professor of pediatrics and molecular neurology and microbiology at Baylor College of Medicine, Houston.
“This outbreak highlights the need to maintain the highest possible vaccination coverage in the United States, along with disease surveillance and outbreak-containment capabilities,” the CDC investigators wrote.
At press time, the CDC reported that from January through April 25, 2008, 64 reports of confirmed measles cases were received from nine states, in which outbreaks were ongoing in four (Arizona, Michigan, New York, and Wisconsin).
A total of 59 cases occurred in U.S. residents, and 54 were associated with the importation of measles from other countries. In all but one case, patients were unvaccinated or had unknown vaccination status. In all, 43 (67%) of the patients were less than 19 years of age and 32 (50%) were less than 4 years old.
'Most people do not think of MMR as a travel vaccine. There is a lot of measles in Europe right now.' DR. BAKER