I know Christmas is upon us because my wife is planning shopping trips, or should I say she is conspiring to separate me from the checking account. This is the time when we are thinking of nice things we can get for special people in our lives. There is something very important that you and your school-age children can get for those around you, a flu shot. That's a real gift of love.

Markets work really well in many areas, because most goods and services people buy affect them and have few side benefits or costs for those around them. Some things we do, such as driving our automobiles, however, pollute the air that others have to breathe. Other things we do, such as keeping our houses well kept, improves our neighbors' house values. Economists call these benefits and costs to those not involved in the trade "externalities" because the benefits and costs are external to the trading process. Sometimes, we just call them "spill-over costs" or "spill-over benefits."

When spill-over costs or benefits are significant, markets don't work as well as we would like. With spill-over costs or benefits, people fail to take the full effects of their actions on others into account. Another way of putting it is that when there are significant spill-over costs or benefits, people are misdirected by the market, doing things that bring harm to others or failing to do things that could be very beneficial to others. When spill-over costs or benefits are substantial, prices in markets just will not reflect all of the costs and benefits involved as they do in other markets.

Economists often suggest that to alleviate this problem of markets we should tax activities that involve external or spill-over costs by an amount equal to the external cost. With this tax or penalty or fine, people cut back on the harmful activities. When the activity involves external benefits, a subsidy gets people to increase the activity that benefits others.

That's where flu shots come in. They are subsidized (the Lafourche Parish Health unit only charges $5), and for good reason. Getting a flu shot not only reduces your chance of getting influenza, but it also reduces the chances of those around you getting the flu as well. Medical doctors (the "Dr." in front of my name has nothing to do with medicine) have long suggested flu shots be given to the very susceptible (the elderly, those in nursing homes, those with weak immune systems, and those with heart disease, lung disease, kidney disease, diabetes, asthma, or anemia). Now, doctors are suggesting that most of the rest of us do the same--to protect not just ourselves, but those at-risk around us as well.

In particular, school-age children are good candidates for flu shots because their close proximity with other children and then coming home to their families make them a primary link in spreading flu around. Also, around Christmas children will be seeing grandparents and great grandparents more. Since the elderly have weaker immune systems than younger folks, flu shots are not as "protective" for them. Having younger folks immunized, especially school children, surely helps to protect our senior family members.

Of course, there are those who should not take the flu shot, such as those with egg allergies (the vaccine is prepared in an egg medium) and those who are allergic to the preservative used in the vaccine. Of course, the nurse or doctor will ask you about allergies and will screen out those who should not take the shot. Remember that you can't get the flu from the shot.

I really like the idea of giving to one by giving something to another. I think I'll give my wife a new trolling motor for Christmas.