More than 1,500 cases of mumps in New York and New Jersey have prompted the CDC to update the public on the outbreak in its Morbidity and Mortality Weekly Report.
According to the CDC, the outbreak appears to have originated with an 11-year-old boy who returned from a trip to the United Kingdom and then attended a summer camp for observant Jewish boys. The illness was transmitted to other attendees and staff members and has since spread as those people returned home. The CDC says 97 percent of the people with mumps “are members of the tradition-observant Jewish community.”
Child with mumps (Photo: Public Health Image Library)
The CDC’s report includes information about how many of the people found to have mumps have been vaccinated – 88 percent had received one dose and 75 percent had received two doses.
The CDC says that, since 1967, when the mumps vaccine was licensed, to the early 2000s, the number of reported cases has gone from 186,000 to less than 500 annually but points out that “the effectiveness of the mumps component of the MMR vaccine is lower than that of the measles and rubella components.”
“The CDC hypothesized that the relatively closed social world of the communities and the large family sizes within them have played a role in preventing the disease from spreading further,” according to a brief from the Center for Infectious Disease Research and Policy.
The Marin Independent Journal‘s Rob Rogers, reporting from a county where an above-average number of parents ask to exempt their children from vaccinations, finds that a sizable group of unvaccinated children can put the whole community at risk.
“Vaccines are very effective, but there is a small failure rate,” said Dr. Rob Schechter, chief of immunization at the state Department of Public Health. “When the whole population is highly immunized, the few vulnerable children are protected by the immunity of the community. But when there is a high rate of exemptions, diseases can spread even to people who are immunized.”
The effects of this high rate of exemptions, many of which are requested by younger parents who may not be familiar with the consequences of vaccine prevented diseases, are starting to show.
An outbreak of chicken pox affected more than 40 students at the Lagunitas and San Geronimo Valley elementary schools in 2007, where 17 and 57 percent of students had received personal belief exemptions from vaccination. In addition, the Lagunitas School District excluded about 70 students from the two schools for three weeks out of concern that they were at high risk of contagion. Many of them had never been vaccinated.
Rogers quotes sources on both sides of the vaccine debate, including public health professionals, parents and a chiropractor who said “Vaccination is based on the medical fallacy that our bodies are stupid … The truth is that the body has a nearly infinite capacity to protect itself against infection as well as other diseases. When I was a kid, everybody got measles, mumps or chicken pox, and nobody died.”
A panel of experts will be discussing this very topic at Health Journalism 2009 this week.