Look at it this way: If the purpose of the vaccine were to make people sick, then in this case it was very effective!
New York (CNN) — More than 1,000 people in New Jersey and New York, many of them adolescent Orthodox Jews, have been sickened with mumps since August, health authorities said Monday.
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Anyone fully vaccinated from mumps receives two doses of the vaccine, according to the CDC. Of the New Jersey cases, 77 percent were vaccinated, Terjesen said.
But the vaccine is not 100 percent effective, according to the CDC. At two doses, the vaccine is 76 to 95 percent effective, the CDC says on its Web site.
Read more at CNN.