While there has been a measurable decline in the number of new HIV cases throughout the United States, pockets of newly-infection people continue to persist, especially in high-risk groups. Injecting drug users (IDUs) are among those that are at increased risk for acquiring HIV because of their drug use practices and sexual behaviors. Further complicating matters is that a substantial number of IDUs are living in major urban areas where HIV prevalence is already documented to be high; many of them may also be unaware of their HIV-infection status.

Since 2004, the CDC’s National HIV Behavioral Surveillance System (NHBS) has monitored disease-associated behaviors among groups considered at high risk for acquiring the virus, including IDUs. In the 2009 IDU cycle, HIV testing was also conducted to provide the first IDU prevalence data in over a decade. During 1993-1997, results from a different CDC survey found prevalence of HIV among IDUs who entered drug treatment centers in the U.S. ranged from 1% to 37%; the overall prevalence was 18%. In the March 2, 2012 Morbidity and Mortality Weekly Report, new data was released on information from 10,073 IDUs from 20 cities in 2009; 9% tested positive for HIV.

Troubling New Trends in HIV

Although the number of HIV infections among IDUs dropped by half over the past decade, the NHBS data showed that testing rates for the virus also decreased. The CDC recommends individuals at high risk get tested for HIV at least annually, but only 49% of IDUs who were interviewed in 2009 reported being tested in the last year. Only 19% reported participating in an HIV behavioral intervention. The number of IDUs reporting being tested for HIV in the past year was significantly lower than data that emerged from NHBS in 2005-2006.

In 2009, the level of risky behaviors reported by IDUs remained high. Among IDUs at risk for acquiring HIV, the following was observed:

34% reported sharing syringes.
46% reported having multiple opposite sex partners.
69% reported having unprotected vaginal sex.
23% reported having unprotected heterosexual anal sex.

In addition, only 72% of IDUs reported ever being tested for hepatitis C infection, a common infection among IDUs. Among men who were IDUs, 7% reported having male-male anal sex in the previous year; 5% reported having unprotected male-male anal sex.

Important Implications on HIV Testing

Results of our data highlight the need for expanded HIV testing and prevention among IDUs. Although new HIV infections among IDUs are declining, there are still critical opportunities to intervene and further reduce HIV infections among IDUs. More work is needed to continue intensifying prevention efforts in communities where HIV is most heavily concentrated. A greater focus on providing prevention services to drug users nationwide is also needed.

Several HIV prevention strategies for IDUs have been shown to be effective, including:

Annual HIV testing and linkage to care.
Prevention and care for HIV-infected IDUs.
Access to new sterile syringes, condoms, and substance abuse treatment.

The findings from our analysis will be used as the CDC continues to focus its prevention efforts on high-risk populations. This information will play an important role in understanding a key component of the HIV epidemic. By taking targeted approaches to HIV prevention, the hope is we’ll be able to further reduce the number of new infections among IDUs.


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