Novel heroin injection practices: implications for transmission of HIV and other bloodborne pathogens

This paper describes injection risk in an out-of-treatment population of young heroin users in Hanoi, Vietnam, including use of a soft-tissue portal known as a "cay ma" (injection sac).

Data from a large cross-sectional survey (N=1270) are used to describe the prevalence of this practice and its association with disease. Additionally, data from an ethnographic substudy on injectors serve to elaborate injectors' rationales for this injection practice.

This practice was common in this sample, appearing soon after initiation of habitual injection. Injectors report that this allows rapid and reliable access to a vein; strategic advantages in a dense urban environment where rapid injection, typically in public settings, is necessary to avoid discovery or arrest. Additionally, this practice is believed to mitigate risk for vein damage from co-morbid promethazine hydrochloride injection.

This practice may draw lymphocytes to injection sites, thereby increasing risk for transmission of bloodborne pathogens. Structural and behavioral interventions are needed for young heroin users in Vietnam.