Measles outbreak associated with an international youth sporting event in the United States, 2007.
BACKGROUND
Despite elimination of endemic measles in the United States (US), outbreaks associated with imported measles continue to occur. In 2007, the initiation of a multistate measles outbreak was associated with an imported case occurring in a participant at an international youth sporting event held in Pennsylvania.


METHODS
Case finding and contact tracing were conducted. Control measures included isolating ill persons and administering postexposure prophylaxis to exposed persons without documented measles immunity. Laboratory evaluation of suspected cases and contacts included measles serologic testing, viral culture, detection of viral RNA by reverse-transcription polymerase chain reaction, and viral genotyping.


RESULTS
The index case occurred in a child from Japan aged 12 years. Contact tracing among 1250 persons in 8 states identified 7 measles cases; 5 (71%) cases occurred among persons without documented measles vaccination. Epidemiologic and laboratory investigation supported a single chain of transmission, linking the outbreak to contemporaneous measles virus genotype D5 transmission in Japan. Of the 471 event participants, 193 (41%) lacked documentation of presumed measles immunity, 94 (49%) of 193 were US-resident adults, 19 (10%) were non-US-resident adults (aged >18 years), and 80 (41%) were non-US-resident children.


CONCLUSIONS
Measles outbreaks associated with imported disease are likely to continue in the US. Participants in international events, international travelers, and persons with routine exposure to such travelers might be at greater risk of measles. To reduce the impact of imported cases, high measles, mumps, and rubella vaccine coverage rates should be maintained throughout the US, and support should continue for global measles control and elimination.
Chen
Tai-Ho
TH
Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, GA.
Kutty
Preeta
P
Lowe
Luis E
LE
Hunt
Elizabeth A
EA
Blostein
Joel
J
Espinoza
Rita
R
Dykewicz
Clare A
CA
Redd
Susan
S
Rota
Jennifer S
JS
Rota
Paul A
PA
Lute
James R
JR
Lurie
Perrianne
P
Nguyen
Michael D
MD
Moll
Mària
M
Reef
Susan E
SE
Sinclair
Julie R
JR
Bellini
William J
WJ
Seward
Jane F
JF
Ostroff
Stephen M
SM
D000328:Adult; D002648:Child; D016358:Contact Tracing; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D038622:Internationality; D007564:Japan; D008297:Male; D008457:Measles / Q000453:epidemiology*; D008459:Measles virus / Q000235:genetics / Q000302:isolation & purification*; D022542:Measles-Mumps-Rubella Vaccine / Q000008:administration & dosage; D008875:Middle Aged; D010356:Patient Isolation; D012367:RNA, Viral / Q000097:blood / Q000235:genetics; D014195:Travel; D014481:United States / Q000453:epidemiology; D055815:Young Adult
D022542:Measles-Mumps-Rubella Vaccine; D012367:RNA, Viral