Q. I am a healthy 70-year-old male. I have never taken a flu shot, but my friends always get their shot. My doctor says it is up to me. I have one friend that seemed to get the flu after taking the shot. What should I do?

Influenza is a respiratory infection that produces fever, chills, sore throat, cough and muscle aches. These symptoms are collectively known as the flu. A virus causes the flu. A virus is simply a piece of bad genetic information that is constantly changing. This means the virus that causes the flu today will not be the same tomorrow in that host's body.

Each year, the Centers for Disease Control and Prevention collect influenza viruses from pigs and people in a foreign land such as China or Africa. Then they select three strains they believe are most likely to cause the flu. As you can imagine, there is a fair amount of guesswork to predict which virus from China will infect people in, say, Iredell County. The theory is that a virus from these countries will travel by some means and reach the U.S.

The CDC notifies drug companies which viruses to produce. They combine them with chicken embryos, kill them with formaldehyde and preserve them with thimerosal, which is a mercury derivative (mercury is a known neurotoxin).

If the CDC guesses right, it is reported that there is a 70 percent to 80 percent effectiveness in temporarily preventing the flu in healthy persons younger than 65. The effectiveness is 30 percent to 40 percent if you are 65 or older. Often, this vaccine is targeted to older adults.

In my mind, the ability to predict the effectiveness of such a vaccination is difficult at best. How can you scientifically determine if the vaccine worked? Was the person's immune system already healthy enough to deal with the virus? Also, how can you know which virus affected a particular person?

When you get a flu shot, you can receive temporary immunity to the particular virus used in the vaccine. The only way to get natural and permanent immunity is to contract and recover naturally from the flu.

Most people believe that a dead virus in a vaccine is safe. After all, how could a dead virus be harmful? If that is true, there should be no adverse reactions associated with a vaccination.

Unfortunately, the most common reactions to a flu shot are fever, fatigue, painful joints and headache. The most severe reaction is Guillain-Barré Syndrome that can occur in two to four weeks of a vaccination. This syndrome is a nerve disorder characterized by muscle weakness, unsteady gait, numbness, tingling, pain and, sometimes, paralysis to one or more limbs or to the face. Recovery can last several weeks. This syndrome is probably rare, but I have not found a report of the prevalence.

Based on my own research, I do not take flu shots, but the choice is yours to make.

Fred

Lowry