Individuals born before 1957 are believed to be immune because they were exposed, but we're not sure about the status of those born between 1957 and the time the vaccine came into widespread use, in the mid-1970s.
The CDC has advised that the vaccine be offered to these individuals living in affected areas.
Suspected cases should be reported immediately to local public health officials, and those individuals should be isolated for 9 days after symptom onset. It is possible the CDC will make further recommendations after this column goes to press.
MMR vaccine has a good safety profile, but adult women may develop a transient arthritis/arthralgia following vaccination. Studies show that 12%–26% of adult female vaccine recipients, compared with 0%–3% of children, will have arthralgia; the rate in adolescent girls falls somewhere in between.
The majority of cases are mild and don't interfere with normal activity.
More information and updates are available from the CDC at www.cdc.gov/nip/diseases/mumps/mumps-outbreak.htm
CDC/NIP/Barbara Rice