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Huddle up for a vaccination talk

These powerful shots can give you an advantage in fighting disease.

My oldest son began junior high football this year, which means learning numerous, sometimes complicated, plays. They're all in a playbook -- a secret catalog of assignments each player must accomplish on each play. If an opposing team found the playbook, it could result in a countermove for each play, shutting down my son's team.

Think of a vaccination as a bug's playbook. When our bodies obtain it, our immune system knows what to expect and how to mount a counteroffensive, shutting down the bug's ability to make us ill.

The idea that we could prevent an illness by "sneaking" its information into our immune system occurred to a country doctor in England in the 1700s. Edward Jenner observed that many milkmaids were resistant to smallpox, a deadly viral infection. He also saw that milkmaids were more likely to get cowpox, a mild form of smallpox. On a hunch, the doctor rubbed cowpox from an infected milkmaid into a farm boy's arm. The youngster developed cowpox and recovered. Jenner then exposed the same boy to smallpox -- and the lad did not get sick. For any number of reasons, such an experiment could not be conducted today, but Jenner's discovery demonstrated that by giving the human body a chance to learn more about a particular infection, it could more effectively deal with the bug when exposed.

Vaccinating an entire population prevents the spread of viruses that cause measles, rubella and smallpox. Vaccinations such as tetanus prevent individual infection from other organisms.

Immunization requirements vary depending on age, habits, vocation and travel, so there's no "one-size-fits-all" approach to vaccinations. However, there are guidelines that your doctor or local county health official can provide to let you know how best to protect you and your loved ones. (See www.cdc.gov/vaccines for more information.) Do yourself a favor and find out more about the pros and cons of vaccinations. Although they represent only one facet of healthy living, they are an important one. Vaccinations are like that playbook: They can give your body the advantage it needs when facing the opponent.

Contributing Editor Tedd Mitchell, M.D., president and medical director of Dallas' Cooper Clinic, writes HealthSmart every week.