Dynamics of the HIV Epidemic in MSM

This special issue documents a unique pattern of the HIV epidemic and its associated factors among men who have sex with men (MSM) in China. In high-income countries AIDS has disproportionately impacted MSM. MSM account for the preponderance of prevalent AIDS cases in the United States, Canada, the European Union, Australia, and New Zealand [1–11]. In contrast, in many low-and middle-income countries the HIV epidemic is driven by heterosexual sex, injection drug use, and/or contaminated blood collection and transfusion, with MSM comprising a small proportion of all HIV cases [10–12]. However, recent data show a trend of increase in HIV cases among MSM in Asia, Africa, South America, and Eastern Europe [8–16]. China is one of the countries facing the challenge of an emerging HIV epidemic in MSM. In China, rates of HIV infection in injecting drug users have fallen, remained stable and at low levels in female sex workers, but markedly increased in MSM. The latest national report revealed that the proportion of newly diagnosed HIV cases due to male homosexual contact has increased from 12.2% in 2007 to 32.5% in 2009; while the national HIV prevalence among MSM had a 4.5-fold increase in the past ten years (i.e., from 1.4% in 2001 to 6.3% in 2011) [17]. HIV cases resulting from transmission associated with illegal blood donations have been largely eliminated following the crackdown on unscrupulous blood donors in the late 1990s. The purpose of this special issue is to improve our understanding of the dynamics of the HIV epidemic and its associated factors that are driving the epidemic among MSM in China. One of the papers in this special issue is by Y. Zhou and colleagues and it describes differences in the prevalence of HIV and syphilis among MSM living in Chinese cities with differing levels of economic development. The authors report a pooled prevalence of 6.5% among MSM nationally, with higher rates in economically less developed cities than in the developed cities. The paper by E. P. F. Chow et al. on the other hand reveals that HIV prevalence among Chinese MSM has increased rapidly in all Chinese regions in recent years. One of the papers summarizes findings from three cross-sectional surveys in Beijing that demonstrate a disturbing rise in HIV incidence among MSM in Beijing. Y. Zeng and colleagues suggest that this epidemiologic trend is not limited to Beijing, as their paper revealed an increase …