Where you live and where you shoot: suggestive data from Valencia, Spain.

Residence appears to exert influence over choices of venues for injection among intravenous drug users (IDUs) in Valencia, Spain. While living in their parents' homes, young IDUs may resort to high-risk venues for injection, particularly chutaderos in which used needles and syringes are often reused. Residence patterns of young IDUs in Spain may be highly similar to residence of IDUs in Italy and Puerto Rico, which also have AIDS epidemics dominated by IDUs rather than men who have sex with men. Intervention in these places needs to take contextual factors of residence into account for effective prevention of HIV infection.