UBC Math Bio Seminar: Dan Coombs

As a disease spreads through a population, the pool of people still susceptible to the disease decreases. Eventually, it becomes unlikely that an infectious person will contact a susceptible person and as a result the number of infectious people starts to decrease. At this point, the fraction of people who are not susceptible is called the herd immunity threshold. The herd immunity threshold can be calculated for simple models and approximated or determined via simulation for more complex models. There has been an ongoing debate about where the herd immunity threshold might lie for the current pandemic. In this talk I will try to summarize the debate, and supply various other opinions.