“…First, the infectiousness of the population of age a and sex s was calculated, for both wild-type and escape mutant viruses (L WTs,a and L Es,a , respectively), as follows: where we have taken into consideration the number of infected individuals in each category and their virological infectiousness (), agespecific transmission rate (T) (48), and the probability that an individual infected with an escape mutant virus will transmit either a wild-type virus (H WT ) or a virus that escapes the vaccine-induced immune response in the recipient (H E ). We then calculated the force of infection for a given sex and age group ( WTs,a , Es,a ) where the empirical effective average rate of partner change is c (13,34) and the rate of sexual mixing between age groups is given by the variable M s,a1:(s*,a2) , the mixing of people of age a1 and sex s with people of age a2 and sex s* (8,23) …”