Mumps Epidemic Spreads; More Vaccine Is Promised

Published: April 20, 2006

IOWA CITY, April 19 In the largest mumps outbreak in the United States in more than 20 years, almost 1,000 people have contracted the disease in the Midwest, the Centers for Disease Control and Prevention in Atlanta announced Wednesday.

The epidemic began in Iowa, where the State Department of Public Health has reported 815 suspected or confirmed cases. It has spread to at least seven other states.

So far, no one has died from the disease, a flu like viral infection that causes swelling of the neck and chin and usually lasts 5 to 10 days. Twenty people have been hospitalized, said Dr. Julie L. Gerberding, director of the Centers for Disease Control.

Because of the effectiveness of the vaccine for measles, mumps and rubella, introduced in 1967, most people think of the mumps as a childhood illness that had been eradicated in the United States. But the current outbreak is challenging those assumptions.

About half of the cases in Iowa involve college-age students, most of whom have been vaccinated, said the state epidemiologist, Dr. Patricia Quinlisk. Federal and state health investigators have not pinpointed the origin of the epidemic, but the first cases were identified in December on a college campus in either Iowa City or Dubuque. State officials said they would not name the campus because such information was medically privileged.

Dr. Gerberding said the disease had spread quickly because of the dense concentration of students in affected cities and because the vaccine is not perfect. It has about an 80 percent efficacy rate for people who have been inoculated with one dose, and a rate of about 90 percent for people who have received the recommended two doses.

"We have absolutely no information to suggest that there's a problem with the vaccine," Dr. Gerberding said. "What's going on here is basically a number of people who haven't received both doses, coupled together with people who have received the vaccine but are susceptible anyway, living in crowded conditions like college dormitories or mixing up with other students at spring break or during holidays, and setting up a cascade of transmission that's going to take a while to curtail."

In recent years there have been 250 to 300 mumps cases annually in the United States, said Dr. Jane Seward, acting deputy director of the division of viral diseases for the C.D.C. The last significant outbreak was in 1989, when Kansas had 269 cases. This time, the states with the most cases, after Iowa, are Kansas, Illinois and Nebraska.

Chase Hardin, 19, a freshman at the University of Iowa, in Iowa City, had a stiff neck in early March, but did not think anything of it until "it looked like someone had stuck an orange in the side of my neck."

"I had no clue that I could get that," said Mr. Hardin, who was vaccinated as a child. "I thought it was something of the past."

Christine F. Cassa, a University of Iowa freshman, got the mumps a few weeks ago, along with four or five other students on her dormitory floor. She said she had heard of about a dozen cases in her 900-student dormitory, Burge Hall.

"The dorms are so like close quarters," Ms. Cassa said. "You're around so many people, and you don't think about what you're touching and what you're drinking, and people share a lot of stuff."

Since December, the university's student health service has confirmed 55 cases, said Lisa James, associate director of student health.

Because of the wide range of symptoms, from achy limbs to swelling, officials did not initially consider mumps a possibility.

"Now we're testing a lot of students, even with mild symptoms, especially if the students say they've been in contact with someone who's had it," Ms. James said. Students who have symptoms are told to isolate themselves for at least five days.

Officials say it could be worse. "We're seeing really very low attack rates," Dr. Seward said. "If we didn't have the high two-dose coverage, we'd be seeing thousands of cases, or tens of thousands of cases."

Dr. Gerberding said the main step the C.D.C. was taking was to provide an additional 50,000 doses of the mumps vaccine, half donated by Merck.

The Iowa Public Health Department is trying to contain the outbreak through public education and inoculation.

"It's hard to say what comes next," said Dr. Quinlisk, the state epidemiologist. "When mumps was around, it tended to be a winter and spring disease, and it tended to go down in the summer. We'll be waiting to see if Mother Nature gives us a little help."