Needle Exchange and Drug Treatment More Effective HIV Prevention

For injection drug users, the most productive and cost-effective approach to managing the spread of HIV is expanding syringe exchange and drug treatment, as well as promoting antiretroviral treatment for those already infected with HIV, according to a new study by researchers at Yale School of Medicine.

Published in the January issue of American Journal of Public Health, the authors, led by Yale Public Health professor Robert Heimer, found that the Centers for Disease Control and Prevention’s (CDC) new approach of promoting HIV testing, “Advancing HIV Prevention,” may not be best for injection drug users.

Heimer, professor in the Department of Epidemiology and Public Health at Yale School of Medicine, said the CDC policy is based on the presumption that the HIV epidemic can be curtailed in great part by promoting HIV testing and that more resources should go to expanded testing of high-risk populations. However, the results reported in this study revealed that testing was already widespread for urban injectors.

Heimer and co-authors analyzed interviews conducted with 1,543 injection drug users in five cities, including New Haven and Hartford, CT, Springfield, MA, Chicago, IL, and Oakland, CA. Access to sterile syringes through syringe exchanges or at pharmacies with a prescription was not available in all cities. Injection drug users who participated in the study were asked if they had been tested for HIV and if they had ever been told they were HIV positive. From this, the research team estimated what percentage had never been tested and what percentage did not know their status.

Ninety-three percent of injectors had been tested, and of those currently in need of testing, 90 percent were tested in the past three years and 70 percent within the past year. Less than three percent were infected with HIV without their knowledge. Women and syringe-exchange participants were more likely to have been tested at least once, and in the recent past. The team estimated the number of undetected infections among urban injection drug users in the United States to be fewer than 40,000.

“Our results highlight the need for shifting prevention dollars for urban injection drug users,” said Heimer, who is also an associate professor of pharmacology at Yale. “It is more important to expend scant resources on effective primary and secondary preventive programs including access to clean syringes and helping users get into treatment for their addiction.”

Heimer emphasized needle exchange programs, substitution therapy like methadone and buprenorphine, and engaging those injection drug users already infected with HIV in supportive anti-retroviral therapy. He said these approaches have been shown to decrease the incidence of new infections at rates sufficient to save money.
“When it comes to urban injection drug users, money will be wasted on low-impact, low-yield counseling and testing programs,” said Heimer. “Prevention programs should not be compelled to generalize and accept a single approach to preventing disease transmission. Injection drug users should not be lumped in with other high risk groups. Instead, tailored programs designed with their unique needs in mind will yield better outcomes.”

Since the study was conducted, Heimer and his colleagues have been working to immunize injection drug users against hepatitis B, as well as developing other interventions designed to reduce HIV infections in drug using populations.

Other authors on the study were Lauretta Grau, Erin Curtin, Kaveh Khoshnood and Merrill Singer.

Citation: American Journal of Public Health, Vol. 97, No. 1 (January 2007)