To analyze the epidemiology of a nationwide mumps epidemic in the Netherlands, we reviewed 1,557 notified mumps cases in persons who had disease onset during September 1, 2009-August 31, 2012. Seasonality peaked in spring and autumn. Most case-patients were males (59%), 18-25 years of age (67.9%), and vaccinated twice with measles- mumps-rubella vaccine (67.7%). Nearly half (46.6%) of cases occurred in university students or in persons with student contacts. Receipt of 2 doses of vaccine reduced the risk for orchitis, the most frequently reported complication (vaccine effectiveness [VE] 74%, 95% CI 57%-85%); complications overall (VE 76%, 95% CI 61%-86%); and hospitalization (VE 82%, 95% CI 53%-93%). Over time, the age distribution of case-patients changed, and proportionally more cases were reported from nonuniversity cities (p<0.001). Changes in age and geographic distribution over time may reflect increased immunity among students resulting from intense exposure to circulating mumps virus.

dx.doi.org/10.3201/eid2004.131681, hdl.handle.net/1765/82867
Emerging Infectious Diseases - (Open Access)
Erasmus MC: University Medical Center Rotterdam

Sane, J, Gouma, S, Koopmans, M.P.G, D.V.M., de Melker, H.E, Swaan, C, van Binnendijk, R.S, & Hahné, S.J. (2014). Epidemic of mumps among vaccinated persons, the Netherlands, 2009-2012. Emerging Infectious Diseases - (Open Access), 20(4), 643–648. doi:10.3201/eid2004.131681