Dear Dr. K: I read that since I’m 68 years old I won’t get as good immunity from the flu shot as a 30-year-old. Am I wasting time by getting vaccinated?

The complete and total answer to your question is “No.” However, let me elaborate.

The issue at hand is immunosenescence, or aging of the immune system. Just like other parts of our body, our immune systems age. It is for that reason that persons over age 50 are more likely to get shingles and to die from influenza. We (I can say that since I’m over 50) also are more likely to get bacterial pneumonia, urinary tract infections, meningitis, gastroenteritis and tuberculosis.

Because of these risks, it makes it all the more important to take preventive steps to bolster our immunity.

People over 65 get only 56 percent of the protective effect of flu vaccine and only 65 percent of the protective effect of the pneumonia vaccine, as compared to young people. Still, that 56 and 65 percent improvement is better than 0 percent.

There has been intense research on the aging immune system, especially with the wave of baby boomers enlarging the elderly population. One unexpected finding was that in addition to increased risk of infection in people over 50, there is a specific infection that by itself can actually speed the senescence of the immune system. The culprit is a virus called CMV – Cytomegalovirus.

As it turns out, this dastardly virus reduces the helper T-cell lymphocytes which are so important in building good immune function. CMV is in the family of herpes viruses and once you’re infected, it stays with you life long.

Since CMV is fairly common, there is intense research into finding a way to prevent its immunologic mischief.