Dear Doctor Column, May 15, 2006

Complete Vaccination Best Protection Against Mumps

Question:

My 3-year-old daughter was vaccinated for mumps when she was about a year old, but I’m concerned about the recent outbreak. I’ve heard even people who have been vaccinated are getting sick. What’s the best way to protect my family?

Answer:

Before the era of routine MMR (measles, mumps, and rubella) vaccination, almost all children got mumps, a viral infection that causes fever, headache, muscle aches, loss of appetite, and swollen salivary glands. Mumps gets its name from this characteristic swelling, which most often occurs in the parotid salivary glands, located in the cheek between the ear and jawline.

Although the infection is now rare, areas of the midwest are experiencing an unusual outbreak of mumps. The recent rash of cases began in December 2005 and has affected more than 1000 people — mostly older teens and young adults between 18 and 25 years, according to the latest Centers for Disease Control and Prevention (CDC) estimates. Most of these people live in Iowa, but the disease has spread to at least eight nearby states, including Illinois, Indiana, Kansas, Michigan, Minnesota, Missouri, Nebraska, and Wisconsin. There are usually fewer than 300 cases of mumps reported in the United States each year, making the current outbreak the largest in the last two decades.

CDC officials have emphasized that complete MMR vaccination remains the best protection against mumps. Complete vaccination means two doses of the vaccine, which provide maximum protection against these childhood infections. Like most children, your daughter received her first mumps vaccination when she was about a year old. Children typically get their second MMR vaccination when they are aged 4 to 6 years. However, your pediatrician can administer the second dose before age 4 — the only restriction is that 28 days must pass between the first and second dose.

Because the mumps outbreak is mainly affecting college-aged individuals and not young children, CDC is not currently recommending that children younger than 4 years get their second vaccination any earlier than usual. If cases of mumps start to appear in younger children, CDC may revise these recommendations.

The best thing you can do right now is to make sure you and your family are vaccinated. All family members older than 4 years should be fully vaccinated with both MMR doses. Check with your doctor to make sure everyone’s vaccinations are up to date. You can also discuss the advisability of earlier immunization for your daughter.

The MMR vaccine is effective against the strain of mumps now spreading through the midwest, however, as you noted, many of the people who have recently gotten mumps have been immunized. The reasons for this are not yet clear. The vaccine is not 100% effective — one dose prevents about 80% of cases, while two doses prevent about 90%. CDC suspects that less-than-100% vaccine protection coupled with inadequate vaccination may be factors in the current outbreak, noting that some college-aged individuals may not have received both doses of vaccine. Because they often live in crowded conditions, college students are susceptible to infectious diseases. Once infected, they can easily spread the illness to friends and family.

There is no specific treatment for mumps. With supportive care, most people recover without complications. Severe complications are rare, but can include:

• Inflammation of the brain and tissue covering the brain and spinal cord (encephalitis and meningitis)
• Inflammation of the testicles (orchitis)
• Inflammation of the ovaries or breasts (oophoritis and mastitis)
• Miscarriage, particularly in early pregnancy
• Deafness, which is usually permanent.

Like the common cold, mumps is usually spread when infected people cough or sneeze, exposing others to the mucus and droplets from their nose or throat. After exposure to the mumps virus, it can take 12 to 25 days for symptoms to appear. People with mumps are contagious for about 3 days before symptoms begin and can pass the illness to others for about 9 days after they start to feel sick.

People with mumps should not go to child care, school, or work for at least 9 days after symptoms appear. If you come in contact with someone you suspect has mumps, you should immediately check your immunization status with your doctor. Your doctor also can explain the signs and symptoms of mumps you need to look for. If symptoms develop, you should seek medical care right away.

To keep up with the latest news on the outbreak and CDC recommendations regarding MMR vaccination, go to www.cdc.gov/nip/diseases/mumps/default.htm.