Probability and Pandemics (CPI #6) When using a calculator to perform calculations, write out the numbers and calculation you asked it to perform. For example, instead of writing Prirolling doubles]=17% you should write Prirolling doubles] = = 17% to indicate what numbers you used. 1. The following problem focuses on the actions of individuals and those actions' effects on the spread of an epidemic. We first need to introduce some terminology. In epidemiology, an "effective contact" is an interaction between an infectious person and a susceptible person that leads to the susceptible person being infected. It is the combination of a contact between a susceptible and an infected person together with a transmission event once that contact has occurred. The average number of effective contacts per infected person is called the basic reproductive number for the epidemic, abbreviated Re- When R. 1 implies the epidemic spreads (i.e., the number of infected individuals increases over time). a. Suppose that the average infected person has contact with 80 susceptible people during the span they are infectious, and each contact has a 3% chance of transmission. Determine the average number of effective contacts per infected person, which is described as R. above. Also interpret the R. in terms of epidemic spread. b. Suppose that lockdowns, quarantine, or other countermeasures cut the number of contacts per infectious person by 40%. Determine the new number of contacts and use the same rate of transmission to determine the corresponding R.. Interpret that R. in terms of epidemic spread. c. Suppose that the transmission rate could be reduced by 45% when both people wear masks (i.e., 45% is a relative risk reduction for transmission). Determine the new transmission rate and use the original 80 contacts figure to determine Ro. Interpret that R. in terms of epidemic spread. d. Combine the countermeasures from b and c, using the reduced number of contacts and the reduced transmission rate. Determine the corresponding value of R. and interpret it in terms of epidemic spread