"In the early 1990s, about 40 percent of IDUs in New York City were HIV-infected, while only about four percent of IDUs in Los Angeles were infected with HIV. Yet in both cities, about 25 percent of gay men were HIV-infected. The solution to this discrepancy is found in the distribution and use of black tar heroin and is due to its unique chemical properties," said the study's lead author, Daniel H. Ciccarone, MD, MPH, assistant professor in the UCSF departments of family and community medicine and of anthropology, history and social medicine.

The study, published in the December 2003 issue of Substance Use & Misuse, examined data from the Drug Enforcement Agency (DEA) on the predominant types of heroin used in 20 US cities from 1990 to 1993. This data was compared with estimates published in the American Journal of Public Health in 1996 of the percentages of both IDUs and gay men infected with HIV in the same cities during the same time frame.

In cities west of the Mississippi, black tar heroin - a dark, gummy, resinous substance from Mexico - is the type of heroin predominately available. On the East Coast, white and light brown powder heroin from South Asia and South America is the type predominately available. Study findings showed the percentage of IDUs infected with HIV was sharply lower in cities where black tar heroin use predominated compared to cities where powder heroin use predominated, a pattern that was not mirrored in the percentages of HIV-infected gay men.

Using ethnographic, clinical, epidemiological, and laboratory data, researchers determined that black tar use by IDUs could lead to less HIV transmission. First, before i
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Contact: Jeff Sheehy
jsheehy@psg.ucsf.edu
415-597-8165
University of California - San Francisco
26-Jan-2004