According to the MMWR, "Among patients aged 7–18 years, the age group with the majority of cases and for whom 2 doses of MMR vaccine is recommended, 93% had received at least 1 dose, and 85% had received 2 doses."
A study released Thursday by the U.S. Centers for Disease Control and Prevention tracked an ongoing outbreak of mumps, largely confined to an orthodox Hasidic Jewish group. The outbreak started among boys attending a religious summer camp in New York State and continued when the youngsters returned to their homes in New York and New Jersey. Currently some 1,521 cases have been reported, with more individuals coming down with the disease.
"The outbreak has been ongoing since the end of June," said study co-author and CDC epidemiologist Kathleen Gallagher. "Ninety-seven percent of cases are among this Jewish community."
Most of the people who have become sick had received the mumps, measles and rubella vaccine (MMR), according to the report. In fact, 88 percent had received at least one dose of the vaccine and 75 percent had received two doses.Outbreaks of mumps are not all that unusual, Gallagher said. "We have had outbreaks of mumps in communities that have had two doses before," she said.