Gaming the flu: How we decide to get vaccinated, or not

September 12, 2012
Gaming the flu: How we decide to get vaccinated, or not
Electron microscopy of flu virus, magnified approximately 100,000 times. Credit: Centers for Disease Control

(Medical Xpress)—As the flu season approaches, public health officials will be campaigning to get people vaccinated, and each of us will have to decide whether to take their advice or not. How will we make those decisions? 

The question is practical and urgent: Young people, especially children, are more likely than older people to spread influenza, but less likely to become severely ill or die from the disease, so health officials want as many young people as possible to get vaccinated. 

In research published in the journal , Rutgers psychologist Gretchen Chapman, employed – the use of mathematical models to study conflict and cooperation between rational decision-makers – to understand how such decisions are made. 

The answer, Chapman found, was straightforward: To get young people vaccinated, make it worth their while. According to her research, young people whose personal rewards are greater if their community's rewards are as great as possible are much more likely to get vaccinated than young people whose personal rewards are not tied to their communities' well-being. Chapman's study is the first to use game theory to examine the of vaccination. 

"In the case of seasonal flu, the specific people who are supposed to vaccinate are young people, and in our game, you can get the young players to vaccinate altruistically, but only if you set the incentives right," Chapman said. 

Chapman and her colleagues set up their game using a laboratory to simulate age-dependent decision-making about . They divided 287 undergraduate students into groups labeled "young" and "old." Everyone started the game with 4,000 points and gained or lost points, based on the decisions they made about vaccination. At the end, the researchers paid the students based on their number of points. Students in half the groups were paid according to how many points they earned individually; in the other half, students were paid based on how many points the group earned. Getting vaccinated cost points; getting infected cost points. 

The two sets of rules reflected two sets of assumptions about human behavior. Students playing by the individualist rules were modeling the Nash Equilibrium, named for the mathematician and game theorist John Forbes Nash who proposed it. Essentially, the Nash Equilibrium assumes that intelligent, rational actors will do all they can to maximize their own benefit. Students compensated by their groups' point totals were modeling the Utilitarian Equilibrium, which assumes that each person sees his or her well-being tied to that of his community and makes decisions accordingly. 

 "Young" people who had been told they would be paid according to the group's point total were much more likely to get vaccinated than "young" people who were paid according to their individual point totals. 

The results were in line with the researchers' expectations, if not their sentiments. "It's a little disappointing, a little discouraging, that people don't do this without the incentive," Chapman said.

Chapman added that game theory models the real world; it isn't the real world itself. "The behavior results are a lot less extreme than the theoretical model," she said. "For example, the utilitarian model suggests that all the young people and none of the older people will get vaccinated, but it doesn't work out that way." 

Explore further: Whole communities in Africa could be protected from pneumococcus by immunising young children

Related Stories

Recommended for you

First language wires brain for later language-learning

December 1, 2015

You may believe that you have forgotten the Chinese you spoke as a child, but your brain hasn't. Moreover, that "forgotten" first language may well influence what goes on in your brain when you speak English or French today.

Anxiety can kill your social status

December 1, 2015

Neuroscientists at EPFL identify a brain region that links anxious temperament to low social status. The researchers were able to tweak social hierarchy in animals by using vitamin B3.

Watching eyes prevent littering

December 1, 2015

People are less likely to drop litter if it has printed eyes on it, researchers at Newcastle University, UK, have found. An image of watching eyes reduced the odds of littering by around two thirds.

How can I tell if she's lying?

November 27, 2015

Sarcasm, white lies and teasing can be difficult to identify for those with certain disorders – new video inventory developed at McGill may help

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

1 / 5 (1) Sep 13, 2012
Since the is no real evidence that flu shots work, you have to con people into taking them. I'm 73 and I've never had the flu, or had a flu shot, because the only people I know who have had the flue, are those who had the shot.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.