Notes From the Field: Measles Transmission Associated With International Air Travel—Massachusetts and New York, July—August 2010 FREE

MMWR. 2010;59:1073

On July 8, 2010, the Massachusetts Department of Public Health (MDPH) notified CDC of a case of laboratory-confirmed measles in an unvaccinated airline passenger aged 23 months.¹ The child had arrived hours earlier on a flight from Switzerland and was contagious during the flight. After obtaining the flight manifest, CDC shared locating information with relevant state health departments; of 31 passengers considered exposed (i.e., seated within two rows and any infant seated anywhere on the airplane), 29 (94%) were notified.

On July 28, the New York State Department of Health (NYSDOH) notified CDC and MDPH that one of the airline contacts had developed laboratory-confirmed measles. The ill traveler came to the United States as a chaperone for students from Europe and Asia attending an educational program. During July 20-23 (while contagious and before being isolated), he exposed 270 students and counselors in Massachusetts and New York. Member of this group were scheduled to return to their home countries from July 30 through August 6. Because exposed, susceptible persons who are incubating measles might be infectious 5-21 days after initial exposure, the surveillance period was determined to be until August 14.^2- 3 CDC Quarantine Stations in Boston and New York worked with NYSDOH and MDPH to assess the immune status of contacts before permitting them to fly. Presumptive evidence of immunity to measles was defined as (1) documentation of at least 1 dose of measles-containing vaccine or (2) serologic evidence of immunity.

Of the 270 persons considered exposed, 268 (99%) were cleared to fly as scheduled: 242 provided documentation of vaccination and 26 had serologic evidence of immunity. Two persons lacked evidence of immunity and voluntarily postponed their departures until the end of the surveillance period. CDC requested that the airlines waive any fees for changing flights. No febrile rash illnesses have been reported among exposed persons.

To prevent the spread of measles, international travelers are encouraged to have evidence of measles immunity. Persons with measles or those who might be incubating measles should avoid travel aboard commercial airlines until they are no longer infectious. Organizations hosting international students should consider asking participants to provide documentation of adequate vaccination.

N Cocoros, MPH, R Hernandez, MPH, N Harrington, Massachusetts Dept of Public Health; E Rausch-Phung, MD, CR Schulte, D Blog, MD, New York State Dept of Health. K Gallagher, DSc, Div of Viral Diseases, National Center for Immunization and Respiratory Diseases; A Klevos, MPH, C Kim, MD, N Marano, DVM, F Alvarado-Ramy, MD, Div of Global Migration and Quarantine, National Center for Emerging and Zoonotic Infectious Diseases, CDC.

The findings in this report are based, in part, on contributions by the Westchester County Dept of Health, New York.