Mumps Outbreak Worsening in Midwest

Inadequate Vaccination May Be a Factor in Outbreak

From the WebMD Archives

April 20, 2006 -- The mumpsmumps outbreak in the U.S. presses on.

The numbers keep growing in the midst of the country's largest outbreak of mumps in more than 20 years, More than 1,000 cases have already been reported in eight states.

Mumps has mainly been seen in the Midwest, especially in Iowa, CDC director Julie Gerberding, MD, MPH, told reporters in a teleconference on April 19.

"We're not going to be surprised if there are more cases in more states, just given the nature of mumps and the way this outbreak is progressing," Gerberding said.

None of the cases has been fatal, though up to 20 people have been hospitalized. "Fortunately, it's usually not a serious disease," Gerberding said.

The CDC has committed to make 25,000 doses of the measlesmeasles-mumps-rubella (MMR) vaccine from its stockpile available to help Iowa's vaccination efforts. In addition, drug company Merck has donated to the CDC 25,000 doses of its MMR2 vaccine "that we will use as we see fit to help support the effort to immunize people in the affected areas," Gerberding said.

Latest Numbers on Mumps Outbreak

The web site of Iowa's public health department shows 975 reports of confirmed, probable, or suspected mumps cases in that state alone, through April 19.

In addition, "there are 350 cases reported from seven other states, which include Minnesota, Kansas, Illinois, Nebraska, Wisconsin, Missouri, [and] Oklahoma," Gerberding said, adding that "a handful of other states" may have cases that haven't been confirmed as probable or definite cases.

The mumps outbreak has mainly been seen in college-aged students, but mumps may spread as youths spend time with their families or in their communities, Gerberding said. "We will continue to see some extension of this outbreak into the community level and we need to be prepared for that," she said.

"This is an unstable situation right now. We're not able to reliably predict where this will go," Gerberding said. "We do know what's important about containment, and we are doing everything we can to support the state health officials who are responsible for executing those steps."


Complete Vaccination Recommended

"I have to emphasize that the best protection against mumpsmumps is the vaccine," Gerberding said.

"There's a lot of confusion right now about whether or not this outbreak is related to some problem with the vaccine. I really want to emphasize that while we are of course investigating the outbreak and we will learn more about the efficacy of the vaccine in this particular setting, we have absolutely no information to suggest that there's any problem with the vaccine.

"The problem here is with the lack of complete coverage of the vaccine," Gerberding said.

"Our vaccine program from mumps began in 1967 but just by nature there is a group of college-aged students who may be less likely to have received both doses of the mumps vaccine and are incompletely vaccinated. Therefore, they're susceptible when infection is introduced, and they have a very high chance of getting mumps under those environments."

Vaccine Not Perfect

"Although this is a very good vaccine, it's not perfect," Gerberding said. "About 10% of people who get both doses of the vaccine still remain susceptible to mumps."

Inadequate vaccination, less-than-perfect vaccine protection, crowded living conditions like college dorms, or close contact with family and friends on spring break or holidays could set off "a cascade of transmission that's going to take awhile to curtail and eventually stop," Gerberding said.

Since mumps has been rare in the U.S. for many years, doctors may need to brush up on the disease, which is caused by a virus, Gerberding said.

Headache, fever, tiredness, and swollen saliva glands are among the symptoms. But not everyone with mumps gets swollen glands, and people may not realize right away that they have mumps, giving the disease a chance to spread.

Rare Complications

With mumps, "people are usually ill for a week or so, but in some people, it can have serious complications," Gerberding says.

The CDC lists these severe (and rare) complications from mumps:

  • Inflammation of the brain and/or tissue covering the brain and spinal cord (encephalitisencephalitis/meningitismeningitis)
  • Inflammation of the testicles (orchitis)
  • Inflammation of the ovaries and/or breasts (oophoritis and mastitismastitis)
  • Spontaneous abortion
  • Deafness, usually permanent

Doctors should check with local health officials if they suspect mumps, and people should follow local recommendations about temporary isolation for people with mumps, Gerberding said.

As doctors become more aware of the mumps outbreak, they may be more likely to check for it, resulting in more reported cases, Gerberding also noted.

WebMD Health News Reviewed by Louise Chang, MD on April 20, 2006


SOURCES: Julie Gerberding, MD, MPH, director, CDC. Iowa Department of Public Health: "Iowa Mumps Update through Wednesday, April 19, 2006." CDC National Immunization Program: Mumps: Key Facts."
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