In Taiwan the first case of infection with HIV was reported in 1984 and the number of infections, especially among homosexual and heterosexual sexual contacts, increased gradually until 2004. There was a sudden increase in 2004; in 2005 it reached a peak; and after that the rate of new infections started to decrease. This drastic increase was caused by IDUs. The virus type of IDUs infected with HIV in Taiwan is the same as that of Yunnan prefecture of China, so that it is thought that the trend in China influenced that in Taiwan. The sex ratio of those infected with HIV/AIDS was nine males for every one female in 2007. Youth are the most affected and those in their twenties and thirties have occupied 70 per cent of the total since 2000. In Taiwan free HIV testing is offered at hospitals, to soldiers, sex workers, blood-donors, prisoners, and patients with sexually transmissible diseases (STDs). The HIV infection rate of those tested at hospitals reflected an outbreak among IDUs.

It is thought that the success in reducing infection among IDUs in 2004 was due to a harm reduction program which included methadone therapy to replace injections. In addition to this, the comprehensive response to HIV/AIDS, including HIV testing, prevention education for sex workers, condom distribution, and free treatment helped control the outbreak. This response was officially supported by the AIDS Prevention and Control Act of 1990 and the HIV Infection Control and Patient Rights Protection Act of 2007 (see also Ko et at. 2012: 1273—82).