New approximations, and policy implications, from a delayed dynamic model of a fast pandemic

Chandrika Prakash Vyasarayani; Anindya Chatterjee

Subsequently, we have examined the implications of policy-induced social distancing, incorporated in our model as a time-varying infection rate β(t). Interestingly and promisingly, we have found that an extended period of social distancing, imposed early in the outbreak, followed by an eventual relaxation to usual levels of interaction, can significantly lower the total numbers infected without losing stability of the final state. In the limit of weak growth, the number of infected people is cut in half. For faster growth, the reduction is a little smaller. Additionally, if the probability of an infected person being detected and quarantined is high, and the self-recovery rate not too small, then perhaps even stronger benefits can be obtained by slightly reducing the time until quarantine, τ .