According to the International Centre for Prison Studies, prison occupancy rates are more than 100% in 125 countries, and above 200% in 22 countries. Prison overcrowding is a global problem that undermines efforts to respond effectively to infectious diseases and other health problems. It increases the risk of HIV transmission through sexual and other types of violence and increases exposure to infectious diseases such as tuberculosis for those living with HIV in prisons.
The high incarceration rates of HIV key populations - sex workers, men who have sex with men, people who inject drugs and transgender people - stem from inappropriate, ineffective or excessive national laws and criminal justice policies. These laws are widespread across countries and regions. The work of UNODC on prisons and HIV is closely related to its work on criminal justice and prison reform.
The United Nations Standard Minimum Rules for the Treatment of Prisoners (The Nelson Mandela Rules) recognize that people in prison should enjoy the same standards of health care that are available in the community. The rules also state that health care services should be organized in close relationship with the general public health administration and in a way that ensures continuity of treatment and care, including for HIV, tuberculosis and other infectious diseases, as well as for drug dependence.