Figure 4
From: A sex-role-preference model for HIV transmission among men who have sex with men in China
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 蚁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 蚁c= 0.30 (i.e., MSM do not change behaviour), = 1.8138 for 蚁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 蚁c= 0.30 or decreases to zero), prevalence can be greatly reduced.