Figure 4

Comparison of dynamics for HIV-infected MSM. Comparison of dynamics for HIV infected MSM: no intervention, HAART and vaccination. All parameters used were the same as in Figure 2, except the condom use rate ρ^cwas either 0.30 or 0. Additionally, for the HAART strategy, individuals taking HAART extend their lifespan by 5 years. So their death rate d _A is 0.069. For the vaccination strategy, uninfected individuals were vaccinated at a rate of 20%, and the effect of the vaccine is 30% and 70% respectively. For these parameters, we have = 1.3528 for ρ^c= 0.30 (i.e., MSM do not change behaviour), = 1.8138 for ρ^c= 0 (i.e., MSM change behaviour), = 2.8676 for 30% efficacy and = 1.4515 for 70% efficacy. Whether MSM population change their behaviour or not after receiving HAART (in our setting, this means that the condom use rate remains at ρ^c= 0.30 or decreases to zero), prevalence can be greatly reduced.