Background: In the case of COVID-19, many countries have introduced their own policies for prevention. In Sweden, herd immunity policy was implemented and it was difficult to reduce the number of fatalities. In South Korea, the number of fatalities was not high because the public had earlier received a risk warning from the government and followed the policy well. In order to prevent the spread of infectious diseases, the government’s policy is important, but it is also important for the people to agree and follow the policy. As such, an individual’s behavior such as preventive measures and pre-responses may be linked to the prevention of the spread of COVID-19.
Methods: To evaluate the effect of strategy selection between individuals and groups when pre-response action, we incorporate a comparmental epidemic model into a game theoretical framework and use this to fit the cumluative confirmed data of Sweden (Feb. 27 - Mar. 12) and South Korea (Feb. 4 - Mar. 3).
Results: The transmission rate ( β ) is estimated from the fitted model, and the reproduction numbers ( R0 ) of two countries, Sweden and South Korea are estimated by 6.93 and 3.71, respectively. The probability of infection ( φ p ) of Sweden is about 12% higher than that of South Korea. As the probability of attack that an epidemic occurs ( θ ) increases, individuals equilibrium gradually increased than group optimum.
Conclusions: When comparing prevention policies of Sweden and South Korea, it was confirmed that pre-response can be an appropriate preventive strategy against the transmission of infection. The selection of a strategy between individuals and groups can lead to the collapse of altruism that tends to select an action strategy for personal benefit, as the probability of the epidemic attack increases.