Vaccination game

Author: István Scheuring

Recommended age: 10-99

Number of players: 8-99

Space needed for the game: classroom

Difficulty level: 2

Playing time: 10-15 minutes per variant

Preparation time: 2 minutes

Accessories: Blackboard, paper, pen

Short description: Vaccination is voluntary, each of us decide on our own whether to vaccinate ourselves or not. But will there be enough people vaccinated?

Preparations: f you are playing more than one round, players should have paper and pencil, too.

Course of the game: A disease outbreak has erupted among the players, but there is a vaccine that can prevent the spread of the epidemic and also prevent serious illness. Each player, independently of each other, decides whether or not to vaccinate themselves. The spread of the epidemic will only stop if at least 80% of the players vaccinate themselves.

There are some costs or risks involved in getting vaccinated, but if someone catches the infection, there is a certain (unforeseen) chance of getting seriously ill. If there are enough vaccinated people, however, life will return to its pre-epidemic status. Let’s assign numbers to the expected costs and benefits! The following table displays the costs and benefits assigned to the various possible decisions during the game:

Explain the table to the players, i.e. the possible outcomes of their decisions, and then ask them to close their eyes. Each player decides whether to vaccinate themselves or not. Count to three, and those who vaccinate themselves should raise their hands. Count how many have taken the vaccine. If it is at least 80%, the vaccinated will receive 99 points and the non-vaccinated receive 100 points. If the vaccine ratio does not reach this level, vaccinated people lose 1 point and non-vaccinated people lose 10 points. Let's play the game several times! Everyone should keep track of how many points they have collected. Who gets the most points? How many times did the “population” not reach the threshold?

Variant 1: Let’s play the game so that vaccinating ourselves is more expensive than not being vaccinated. That is, the table looks like this:


Let's play the same game as before! To what extent does the vaccination propensity experienced in the former game change with this change?

Variant 2: Play the game so that one half of the players gets points according to the original table (catching the infection is a higher risk than vaccinating ourselves), the other half according to the second table (vaccinating ourselves is a higher risk than not vaccinating ourselves). How does the propensity to vaccinate, compared to the original game, change this time?

Variant 3: The 1) game variant is actually the We are cavemen game, wrapped in a different wording. Let’s use the vaccination and prehistoric frameworks for two separate groups and see in which case will there be more volunteers and vaccinators!

Variant 4: You may want to play the base game with other numeric values. For example, let 99 be 50 instead of -1 in the table. Or try what changes if 90% or 70% vaccination is needed for protection, not 80.

Variant 5: It is also worth trying the game without having to decide in a single round. For example, say at the beginning that there will be 5 laps. Everyone can choose to be vaccinated in any round, but obviously once they have decided they will be vaccinated, that can’t be changed anymore. After each round, the referee will tell you how many people have been vaccinated. At the end of the fifth round, players will receive points based on whether or not they have previously been vaccinated and whether or not they have been vaccinated after the fifth round.

Biological background: Voluntary vaccination poses an interesting dilemma. When there are not enough people vaccinated in the population to achieve community (or herd) immunity, those who have vaccinated themselves are at a lower average risk than those who have not vaccinated (-1> -10). However, when enough people are vaccinated, those who have not been vaccinated are better off, as they did not have to bother with any unpleasant side effects associated with vaccination (99 <100). It is a question of whether, if the players decide independently, they will succeed in achieving herd immunity. With variant 1 we can model the case, when the community estimated vaccination to be a higher risk than catching the disease. For example, many young adults may think this about the Covid-19 epidemic. Variant 2 examines the case where one part of the group considers the bad consequences of vaccination to be more significant and the other part considers the expected disadvantage of the disease to be more significant. With variant 3 we can show that if it is help that causes the cost, the players are more likely to accept the costs.

References: Own idea