Risk factors for mumps at a university with a large mumps outbreak.
OBJECTIVE
Routine measles-mumps-rubella (MMR) vaccine use has greatly decreased the incidence of mumps in the U.S. However, a resurgence of mumps occurred in 2006. We investigated the large outbreak at a university and assessed risk factors for disease.


METHODS
We described the outbreak and conducted a case-control study. We interviewed case students (identified from student health service and health department records) and control students (selected from a randomly ordered administrative list) and assessed their vaccination status. We compared case students with > or = 2 MMR doses and control students with > or = 2 MMR doses in univariate and multivariate analyses.


RESULTS
The mean age of the 174 case students was 20.9 years; 65% were women. Ninety-seven case students and 147 control students were enrolled in the study. Two-dose MMR coverage was 99% among case and control students with complete records. Only 33% of case students reported exposure to someone with mumps. Case students were more likely than control students to be aged 18 to 19 years (vs. aged 22 years, adjusted odds ratio [AOR] = 5.55; 95% confidence interval [CI] 2.09, 14.74), to report exposure to mumps (AOR=2.31, 95% CI 1.13, 4.73), and to have worked/volunteered on campus (AOR=2.91, 95% CI 1.33, 6.33). Also, women in dormitories had increased odds of mumps compared with men in dormitories.


CONCLUSIONS
High two-dose MMR coverage was not sufficient to prevent the outbreak. Further study is needed to better understand the effects of dormitory residency and gender on mumps transmission. Clinicians should be vigilant for mumps in young adults presenting with parotitis regardless of immunization history.
Huang
Angela S
AS
Epidemic Intelligence Service, Office of Workforce and Career Development, Centers for Disease Control and Prevention, Atlanta, GA, USA.
Cortese
Margaret M
MM
Curns
Aaron T
AT
Bitsko
Rebecca H
RH
Jordan
Hannah T
HT
Soud
Fatma
F
Villalon-Gomez
Jose
J
Denning
Patricia M
PM
Ens
Kim A
KA
Hanson
Gail R
GR
Dayan
Gustavo H
GH
D000293:Adolescent; D016022:Case-Control Studies; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D007615:Kansas / Q000453:epidemiology; D008297:Male; D009107:Mumps / Q000453:epidemiology / Q000209:etiology*; D012112:Residential Facilities; D012307:Risk Factors; D013334:Students; D014495:Universities; D055815:Young Adult