Almost a dozen vaccines for adults are routinely recommended by the federal government to reduce the risk of serious disease. They guard people against:
Influenza. Adults over 50 should get a shot to protect against seasonal flu. The vaccine is also recommended for women who are pregnant, immune-compromised people, healthcare workers, people traveling in the tropics or on cruise ships, and people who have household members in those categories.
Caveats: Side effects are generally mild. The vaccine is made using chicken eggs, so people who are allergic to eggs shouldn't get a flu shot. Each year, manufacturers change the formula for the flu vaccine in an attempt to match it to widespread strains of the virus; some matches are better than others, so the shot's effectiveness varies from year to year. FluMist, a nasal spray that contains a live attenuated vaccine, was approved in 2003. It can cause mild flulike symptoms and is not recommended for women who are pregnant or people who are immune-compromised.
Pneumonia. The pneumococcal vaccine is aimed largely at people with risk factors—those over age 65 or with chronic illnesses such as diabetes, heart disease, cancer, or HIV. It's effective in reducing the risk of hospitalization and death in the elderly. People who get their first pneumococcal shot before age 65 should get a booster five years later.
Caveats: Reported side effects are mild, including tenderness at the shot site and mild fever.
Measles-mumps-rubella. Adults born before 1957 are considered immune to this trio of diseases, and most younger adults were vaccinated as children. But people born outside the United States should probably get a shot. That's particularly true for women, because rubella can cause birth defects. The Centers for Disease Control and Prevention also recommends that college students, healthcare workers, and international travelers get a booster. Measles remains much more common in other countries, particularly in Africa.
Caveats: This vaccine contains live virus and thus should not be used by pregnant women or immune-compromised people, including those with HIV and a low count of CD4 immune cells. Side effects include fever, rash, seizure, and temporary joint pain or stiffness.
Meningitis. First-year college students living in dormitories, international travelers, and healthcare workers are the main customers for the meningococcal vaccine, which combats bacterial meningitis. The vaccine has a piece of the bacterium instead of live bacteria and is considered safe.
Caveats: The vaccine doesn't protect against all strains of the Nesseria meningitidis bacterium. About half of recipients get mild side effects, such as a sore arm.
Hepatitis A. Hepatitis A is common in the developing world; the virus is spread in feces and causes flulike illness that can last for weeks or months. The vaccine is recommended for people traveling to less-developed areas overseas, as well as people with risk factors such as intravenous drug use and men who have sex with men.
Caveats: This is a killed-virus vaccine and is considered safe. Side effects include soreness at the injection site, headache, and tiredness.
Hepatitis B. Hepatitis B is a blood-borne virus that causes liver damage. The need for a vaccine is based on a person's risk factors: People who are on dialysis or have HIV or another sexually transmitted disease should be vaccinated. So should healthcare workers, people who use street drugs, men who have sex with men, and people in drug-abuse treatment or correctional institutions. It is more common overseas, particularly in Africa and Asia, so travelers should check with the CDC to see if they need the vaccine.
Caveats: This is a recombinant-DNA vaccine and is considered safe. Side effects include soreness at the injection site and fever. Three shots are recommended, but Gina Mootrey, associate director for adult immunizations at the CDC, says taking "two doses is better than no doses."