The HIV epidemic in Pakistan.

Pakistan's HIV epidemic is fully established and expanding among injection drug users (IDUs) of whom 20% are infected with HIV. Nascent epidemics are seen in some cities among Male sex workers and transgenders who form sexual contacts of IDUs. With involvement of sex workers, Pakistan appears to be following the "Asian Epidemic Model". On the other hand, nearly all patients in HIV clinics are expatriated migrant workers and their immediate relations. Almost all principle population subgroups have at least some cases of HIV in most cities. While universally known risk of HIV transmission are present among sex workers, IDUs, a sub-group of men from the general population and other groups, epidemics among male sex workers have preceded those among female sex workers suggesting local nuances in sex behaviors. Universal male circumcision and limited contact between sex workers and IDUs may have slowed the initial progress of the epidemic thus far although that will change as the numbers of HIV-infected IDUs and their sexual contacts grows. The government runs HIV prevention programs for IDUs and sex workers in many cities, but must enhance the levels of coverage and quality of services provided. The slow early progression has provided a window of opportunity; it must not be allowed to close.