"HIV testing within prison populations has been widespread in central Asia, reflecting sentinel surveillance and mandatory testing policies. HIV prevalence among prisoners ranges from 2% in Kazakhstan to nearly 7% in Tajikistan (figure 2). By the start of 2007, more than 25% of cumulative registered HIV cases in Kazakhstan were in prisoners, and in Tajikistan, a fifth of the registered HIV population are prisoners;32,64 these proportions reflect HIV-testing policies, criminalisation of illicit drug use, and high rates of risk behaviours among prisoners, both inside and outside prison settings.59 In central Asia, 5–25% of prisoners are estimated to have drug dependence43 and up to 70% share injecting equipment.32,69 In one study in Kazakhstan,36 the prevalence of syphilis among prisoners in temporary detention was 5%. The prevalence of tuberculosis among inmates is 60–100-times higher compared with the general population, with high tuberculosis mortality.64"
Claire Thorne, et al., "Central Asia: Hotspot in the Worldwide HIV Epidemic," The Lancet Infectious Diseases, 2010 Jul;10(7):479-88. doi: 10.1016/S1473-3099(10)70118-3