Hypodermic needles are also used by untrained users in recreational intravenous drug use (e.g., injecting solutions of heroin and water). Before governments attained current levels of awareness about the spread of disease through shared needles, hypodermic syringes in many countries were available only by prescription. Thus, in order to limit the spread of blood-borne diseases such as hepatitis and HIV through shared injection equipment, many countries have needle exchange programs in most larger cities. In some countries, such programs are wholly or partially subsidized by the government.