AIDS epidemic at age 25 and control efforts in China

China reported its first HIV/AIDS cases among hemophiliac patients in Zhejiang province in 1985 [1]. In the same year, a foreigner was diagnosed with AIDS in Beijing [2]. There were a few isolated cases of HIV/AIDS identified sporadically but the first HIV epidemic in China was not discovered until 1989 when 146 HIV-positive cases were found among intravenous drug users (IDUs) in Ruili, China's border town with Myanmar in Yunnan province [3].In the early 1990s, the epidemic was mainly along the southwest border regions where more than two-thirds of China's total reported cases of HIV/AIDS originated. The majority of affected people were IDUs, who accounted for about 70% of the country's total reported cases [4]. In the mid-1990s, while the HIV epidemic in border regions slowly spread to nearby regions and inland China, plasma collection activities in central China such as Henan and surrounding provinces caused large numbers of commercial plasma donors to become infected with HIV through infusion of pooled contaminated blood cells [5-7]. The HIV infections among the plasma donor population triggered the second wave of HIV/AIDS epidemic in China. Thereafter a continuous spread of HIV infections among IDU populations persisted. By then, all provinces had reported HIV/AIDS cases, and the epidemic entered a rapid growth phase [4]. The unique characteristics of China's AIDS epidemic in the 1990s were the following: 1) injected drug users and former plasma donors were the two major groups affected by the epidemic, 2) most of the infected patients were young males, and 3) the majority of them lived in rural areas [4].The large scale blood contamination events among plasma donors were quickly controlled within a short period of time after they were discovered [7]. However, the HIV epidemic among the IDU population remained at fast pace and spread to many parts of the country. There was a steady increase of HIV infections among promiscuous groups in several regions of the cou