Just over 1500 cases of mumps have been reported in New York and New Jersey between June and January, almost exclusively in a tradition-observant Jewish community and primarily among teenage boys. Nineteen hospitalizations were reported and no deaths have occured. 88% had received at least 1 dose of mumps-containing vaccine, and 75% had received 2 doses.
Beginning on January 19, 2010, in Orange County, New York, public health officials began offering a third dose of MMR vaccine in three schools despite documentation of the highest level of 2-dose coverage among students in the area, the fact that the federal Advisory Committee on Immunization Practices doesn't recommend it, and no data exists on the effectiveness of a third dose in either reducing the risk for mumps or altering the course of an outbreak.
The story from the CDC maintains "Although mumps vaccination alone was not sufficient to prevent this outbreak, maintaining high measles, mumps, and rubella (MMR) vaccination coverage remains the most effective way to prevent outbreaks and limit their size when they occur," and suggests the data they get from a third shot can be used to guide future options for similar outbreaks.
However, much like the other diseases where incidence rate was already declining when the vaccine was introduced, the number of cases per week has dropped from a peak of 160 in mid-November to less than 20 before the introduction of the third vaccine.
P High, MHS, Ocean County Health Dept, EF Handschur, MPH, OS Eze, MD, B Montana, MD, C Robertson, MD, C Tan, MD, New Jersey Dept of Health and Senior Svcs. JB Rosen, MD, KP Cummings, MPH, MK Doll, MPH, JR Zucker, MD, CM Zimmerman, MD, New York City Dept of Health and Mental Hygiene; T Dolinsky, Rockland County Dept of Health; S Goodell, MPH, B Valure, Orange County Health Dept; C Schulte, D Blog, MD, E Rausch-Phung, MD, P Smith, MD, New York State Dept of Health. A Barskey, MPH, G Wallace, MD, P Kutty, MD, H McLean, PhD, K Gallagher, DSc, R Harpaz, MD, GL Armstrong, MD, L Lowe, MS, R McNall, PhD, J Rota, MPH, P Rota, PhD, C Hickman, PhD, WJ Bellini, PhD, Div of Viral Diseases, National Center for Immunization and Respiratory Diseases. I Ogbuanu MD, A Apostolou, PhD, EIS officers, CDC. (2010). "Update: Mumps Outbreak --- New York and New Jersey, June 2009--January 2010." Morbidity and Mortality Weekly Report February 12, 2010 / 59(05);125-129