Introduction

Reviews

Preventing Disease with Vaccines

Timothy B. McCall, M.D.

Many serious diseases, including polio, measles and tetanus can be prevented by vaccination. In 1989, the a federally-appointed panel of experts, the U.S. Preventive Services Task Force, published a series of guidelines on preventive medicine. The experts evaluated the scientific evidence for and against various preventive measures and made recommendations about which ones were appropriate. The following table lists their advice on vaccines for adults.

Vaccines Recommended for Adults by the U.S. Preventive Services Task Force

• Tetanus and Diphtheria Booster—recommended every 10 years
• Influenza (“flu shots”)--yearly after age 65 or if you have a chronic illness
• Pneumococcal (pneumonia vaccine)--once at age 65 or if you have a chronic illness

Most adults at risk never receive the vaccines of proven value. For example, about 40,000 people, mostly older ones, die of pneumococcal diseases like pneumonia every year yet only about 14 percent of those at risk get the vaccine. 20,000 people die of influenza annually. To put these numbers in perspective, less than 1,000 children die annually in the United States of diseases preventable by vaccinations.

When deciding whether or not to be vaccinated, consider that for recommended vaccines, the risk of the disease the vaccine prevents is usually higher than the risk of the vaccine. Vaccines do have side effects, as the infamous 1976 swine flu vaccine demonstrated, but the diseases they prevent usually pose a greater risk.

Consider the example of flu shots. Influenza is a serious viral infection that causes severe headaches, high fevers and awful body aches. It shouldn’t be confused with the “flu” which many people use as a synonym for the much milder common cold. Young, healthy influenza victims often end up in bed for a week. For those weakened by chronic disease or old age, influenza can kill.

In my experience, however, many patient refuse flu shots out of fear of side effects. Several have told me they got sick in a prior year following their flu shot and thought it was related to the vaccine. But it may have just been a coincidence.

Take a look at this study: To test how common side effects of flu shots are, researchers from three hospitals in Minnesota compared the reactions of elderly patients given either real flu shots or fake shots containing salt-water. Except for minor arm soreness at the injection site, there were no differences in the side effects reported by the two groups. The researchers concluded that most symptoms people attribute to flu shots were due either to illnesses that coincidentally occurred at the same time or to people’s increased awareness of their body in the period immediately following a flu shot.

Some vaccines not recommended for the general public, are appropriate for people at increased risk of particular infections. German measles, also known as rubella, is of particular concern for woman in the childbearing years because it can cause severe birth defects. Young women who might become pregnant who have not had the rubella vaccine should have a blood test done. If the test shows no protective antibodies, they should have the vaccine and avoid pregnancy for three months.

One of the newest vaccines is for hepatitis B. IV drug users, sexually-active gay men and anyone exposed to blood, such as health care workers and dialysis patients, should get this safe and effective vaccine. Sexual partners of people with hepatitis B should also get it. Although hepatitis B causes fewer deaths than AIDS—around 5,000 per year in the United States—it is almost 10 times as easy to catch.

I have written in earlier columns about the need to be open with your doctor about your sexuality and drug habits. Vaccines are another reason to do so because the information could affect which ones are recommended to you. Only about 10% of people at risk for hepatitis B have been vaccinated.

By getting vaccinated you not only protect yourself from infection, you protect others who might have caught the infection from you. People who decline vaccines due to the perceived risk benefit from the risk others have taken.

I am generally healthy and not at high risk if I get influenza. Some of my patients, though, are. Since the flu shot is only about 70% effective, I have one every year mostly to protect them. If you have elderly parents or friends with chronic illnesses, you may want to consider more than just your personal risk when deciding whether to be vaccinated.

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