A SIS disease spreads through a population of size K = 30, 000individuals. The average time of recovery is 10 days and theinfectious contact rate is 0.2 × 10^(?4) individuals^(?1) day^(?1). (a) The disease has reached steady-state. How many individualsare infected with the disease? (b) What is the minimum percentagereduction in the infectious contact rate that is required toeliminate the disease? (c) By implementing a raft of measures it isproposed to reduce the value of the infectious contact rate to onepercent of its initial value. Will this be su?cient to eliminatethe disease within twenty-eight days? (d) Is it feasible toeliminate the disease within twenty-eight days solely by reducingthe value of the pairwise contact rate? (e) How may days will the‘raft of measures’ have to be maintained if we are to eliminate thedisease?
