Vaccinate one child and many benefit

By Edward Lotterman

St. Paul Pioneer Press
Published: 03/11/2011


As usual, Minnesota is above the national average in the proportions of children who are vaccinated against infectious diseases, according to a news item this week. Unfortunately, those proportions are declining, and we are not so far above the average as we used to be.

Is this a problem? What, if anything, should we want government to do about it? This is an issue where considerations of individual liberty clash particularly strongly with the health of society as a whole.

We live in an era in which there is greater emphasis on human liberty and personal responsibility than was true for many years. Many people oppose intrusive government. Few things are more intrusive than government telling people that they must have their children injected with various vaccines. Moreover, there always have been members of some religious groups that find vaccination against their faith. So we don't have a federal law per se that requires vaccinations. There are, however, laws in some states that do require vaccinations and a federal law that requires them before attending educational institutions.

Those suspicious of government coercion ask why government should be involved at all. Why are vaccinations any different than getting a tumor removed, a hernia fixed or a pill prescribed to reduce blood pressure? If people think childhood vaccinations have greater benefits than costs, let them go ahead and get their kids vaccinated. If they don't think so, let them do without and run the risks of getting sick.

The problem is that vaccinations against infectious diseases are different from medical care for noninfectious maladies. Vaccinations have what economists call "spillover benefits." That is, they do good things for society that go beyond the protection afforded to the person getting the shots.

This is because of a phenomenon called "population immunity." Higher rates of vaccination reduce the risks of epidemics. They also reduce the risk of even nonvaccinated people getting the disease, epidemic or not. The reason is that as the fraction of the population that could get the disease shrinks, the harder it is for the pathogen to spread from one person to another. The risks of an unvaccinated person getting a disease fall extremely low well before vaccination rates approach 100 percent.

This introduces perverse incentives. It benefits society as a whole for people to get vaccinated. But if most people are getting vaccinated, any single individual can avoid the discomfort, risk and expense of being vaccinated and still benefit from the reduced risk of getting sick that spills over from others taking the precaution.

This leads to what logic professors call a fallacy of composition, of assuming that what is true for an individual is necessarily true for a group. Any one individual may be better off by "free-riding" and not getting vaccinated. But if everyone avoids vaccination, society as a whole will be much worse off because dangerous diseases will spread throughout the population.

Economists agree that when all the costs and benefits of some product or service are borne by the person deciding to consume it or not, there is no need for government to act. If no one else is affected by my eating a muffin or reading a magazine, there is no reason for government to either promote or retard muffin eating or magazine reading.

But when others are affected, society is worse off if government does not act.

Both history and economic theory demonstrate that there are some goods or services, such as national defense or fire protection, that have large spillover benefits and that will not be produced in optimal quantities in free, private markets. Society gets fewer of its needs and wants met than if government "intervenes" to use resources to provide such "public goods."

A muffin or a magazine is a purely private good. A police cruiser is largely a public good. But many other things, including education and vaccinations, fall somewhere in between, with some benefits accruing solely to the individual getting educated or vaccinated and other benefits spilling over to the rest of society.

Educating everyone in basic literacy and numeracy has enormous spillover benefits for society in the form of economic productivity. Getting a Ph.D. in economics or archeology may benefit the student, but it does little extra for society. So we subsidize and mandate education through age 16 but let public support taper off after high school, with government paying nearly all of the cost of education through the secondary level, but proportionally less for college and graduate school.

We indirectly coerce people to get vaccinated against the most dangerous infectious diseases. We also provide some subsidies, but we expect households or their insurers to pick up much of the cost. Some of the decline in vaccination rates is attributed to declining levels of reimbursement by private insurers and Medicaid. I think this is a mistake.

Private demand for vaccinations and public support for government subsidies of vaccination are driven by perceived risk. I was one of more than 60 kids home with the measles out of a school of 110 students when I was in the third grade. My cousin lived with a hand withered by polio. I knew people scarred by smallpox when I worked in Brazil and Peru. That is why I think government should both subsidize vaccination and "encourage" it, subject to exemptions for legitimate religious beliefs.

But I am getting to be an old geezer. Younger generations that have never seen the scourge of such diseases evidently don't feel the same urgency.

St. Paul economist and writer Edward Lotterman can be reached at elotterman@pioneerpress.com.