TUCSON, AZ (Tucson News Now) - The United States is being hit with the worst mumps outbreak in a decade, with the number of cases at 2,879 from January through early November.
There have been six cases in Arizona from the first of the year through late November.
Three of them were in Pima County, but the Pima County Health Department said they all were probable cases, not confirmed cases.
The contagious disease is caused by a virus spread through saliva and mucus.
There's a vaccine for this disease.
The CDC said six states have reported more than 100 cases this year.
They are Arkansas, Iowa, Indiana, Illinois, Massachusetts and Oklahoma.
Many of the cases have been on college campuses.
University of Arizona Director of Health Promotion and Preventive Services David Salafsky said there are no reported mumps cases on the UA campus.
The UA requires that students show proof of immunization before they can enroll in classes.
Mumps has flu-like symptoms and occasionally causes the swelling of salivary glands.
The causes the "chipmunk cheek" look some patients get.
Mumps is not considered life-threatening, but it can have lasting side-effects.
The experts said people who have had the mumps have protection.
The vaccine is considered close to 100 percent effective.
Dr. Sean Elliott, the Medical Director, Infection Prevention at Banner-UMC said in during an outbreak, those who have not been vaccinated are most at risk.
"It's known that in an outbreak setting, three percent of vaccinated individuals could get the mumps," Elliott said. "That's not a huge number versus 50 to 70 percent of un-vaccinated individuals. So in an outbreak setting you know who's going to get hit the hardest: The un-vaccinated. There's really no health benefit though to re-vaccinating a fully immunized person for the mumps."
Elliott said college campuses can get hit harder than other areas because of students' lifestyles that include close proximity to each other, lack of sleep, bad eating habits and different hygiene habits.
Arizona and Pima County health officials say they'll continue monitoring for the disease, but Elliott said there is no cause for concern in this state.
"Right now there are no notices, no alerts, no warnings on the campus at the University of Arizona, in Pima County, in Arizona, which is reassuring. That's wonderful. Doesn't mean that we stop looking, however," Elliott said.
To learn more about mumps and the vaccine, click HERE.
To learn more about the outbreak, click HERE.