Mumps cases in 2016 have reached a decade-long high, according to data released by the Centers for Disease Control and Prevention (CDC) this week.
As of Dec. 3, 2016, 46 states and the District of Columbia in the United States have reported 4,258 mumps cases to the CDC. In 2010 there were 2,612 mumps cases reported, while there were only 229 reported in 2012. In 1967, the year the U.S. mumps vaccination began, there had been about 186,000 mumps cases reported each year, but the actual number was likely higher due to underreporting, according to the CDC.
In 2016, officials reported more than 100 cases in each of the following states: Arizona, Iowa, Indiana, Illinois, Massachusetts, New York and Oklahoma.
Being in a crowded environment like living in a dormitory or playing on a sports team can increase the risk of mumps outbreaks, as can sharing utensils or cups, or exchanging saliva. But getting vaccinated can also minimize the size, duration and spread of mumps, according to the CDC.
The MMR vaccine— of which the CDC recommends two doses beginning when children are 12 to 15 months old— prevents most cases of mumps and other potentially serious complications from the disease. Two doses are 88 percent effective at protecting against mumps, while one dose is 78 percent effective, according to the CDC.