Chickenpox: Not Just Kid's Stuff

Q: I’m 43 and have never had or been exposed to chickenpox. My doctor ran a blood test to determine this. What is involved with the vaccine she wants to give me? And why is my lack of exposure to the virus such a big concern at my age?

A: It’s a good thing your doctor checked because chickenpox can strike adults who have not been exposed to, had or been vaccinated against this disease. Adults who do come down with chickenpox tend to have more persistent and bothersome symptoms than kids do. Although rare, chickenpox has a higher rate of complications in adults, including pneumonia (one in 400 adults), inflammation of the brain (encephalitis) and skin infections. If contracted by pregnant women, the disease also has the potential for causing birth defects. Fortunately, there is a well-tolerated vaccine (two doses given four to eight weeks apart) that will greatly decrease the risk for getting chickenpox.

Even though most people have had chickenpox (varicella) by the age of 15, you fell into the rare category of adult who not only hasn't had the disease, but doesn't seem to have any antibody protection against it from previous exposure to those who did. This is unusual because chickenpox is a very contagious disease that’s caused by the varicella-zoster virus. It can be spread by contact with chickenpox blisters or through the air by fine droplets given off when the infected person coughs or sneezes.

After a non-protected person is exposed, symptoms usually develop within 10-21 days. These include irritability, fever, sore throat, dry cough, fatigue and a rash that produces an average of 300 blisters over the body (usually starts on the scalp and back). These blisters last an average of five to seven days and then tend to dry up, crust over, and gradually fade away over a two- to three-week period.

While the symptoms I just mentioned are not considered severe, complications leading to hospitalization and even death can occur, especially among adults who lack antibodies to fight off the disease.

Since your doctor confirmed you do not have detectable antibody levels that would kill the virus if you were exposed, she has recommended the chickenpox vaccine. This immunization is 70 percent to 90 percent effective in preventing this illness, as well as 95 percent effective in reducing your risk for a serious form of the disease. According the National Foundation for Infectious Diseases, this vaccine is recommended for "all susceptible children and adults,” especially those in the following groups:

• Health-care workers
• Household contacts of immunocompromised persons
• International travelers
• Military personnel
• Non-pregnant women of childbearing age
• Teachers and daycare workers
• Inmates and staff of correctional institutions
• Residents and staff in other institutional settings.

As for the vaccine's side effects, the most common are pain, mild fever, swelling and redness at the injection site. Serious reactions are extremely rare. However, there are certain people who should not receive the shot. They include pregnant women, those with weakened immune systems (HIV, cancer, etc.) or those being treated with immune-suppressant medications.

Find More on MSN Health & Fitness:

• Reality Check: Chickenpox
• Control the Itching
• Shingles in Seniors

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Robert Danoff, D.O., M.S., is a family physician and program director of The Family Practice Residency, as well as the combined Family Practice/Emergency Medicine Residency programs at Frankford Hospitals, Jefferson Health System, Philadelphia, Pa. He is the medical correspondent for CN8, The Comcast Network, a regular contributor to Discovery Health Online and a contributing writer to The New York Times Special Features. (Read his full bio.)