HIV Infection and HIV-Associated Behaviors Among Injecting Drug Users -- 20 Cities, United States, 2009

Editorial Note

The 2009 data in this report provide the first estimates from a large-scale survey of HIV seroprevalence among IDUs since 1993-1997, when CDC conducted anonymous HIV testing among IDUs entering drug treatment centers in 14 MSAs.⁶ In the study of IDUs entering drug treatment, HIV prevalence was found to be 18% (range by MSA = 1%-37%). In this analysis, 9% of IDUs tested positive for HIV infection. Furthermore, 45% of those testing positive were unaware of their infection.

Risk behavior prevalences in this report showing that IDUs are at risk for acquiring HIV infection through their sexual behavior in addition to their drug use practices are similar to previously reported NHBS surveillance data.⁷ Compared with a similar analysis of IDUs interviewed during 2005-2006, lower percentages in this 2009 study reported receiving HIV interventions (19% compared with 30%) and HIV testing (49% compared with 66%) in the previous 12 months.⁷ These results highlight the need for expanded HIV testing and prevention among IDUs. The combination of declining HIV prevalence and high-risk behavior represent a critical intervention opportunity to further reduce HIV prevalence and incidence among IDUs.

Consistent with previous reports,⁸ this analysis found higher HIV prevalence among Hispanic and non-Hispanic black IDUs than non-Hispanic white IDUs. However, minority IDUs were neither more nor less likely to have received HIV testing, participated in HIV behavioral interventions, or engaged in risk behaviors than white IDUs in the 12 months preceding the NHBS interview. These data suggest factors not assessed by this study might be contributing to racial/ethnic disparities in HIV prevalence among IDUs.

The findings in this report are subject to at least three limitations. First, some participants might not have accurately reported their behavior to interviewers, and results might be affected by social desirability bias. Second, because no method of obtaining probability samples of IDUs exists, the representativeness of the NHBS sample cannot be determined. Although respondent-driven sampling adjusts for some selection biases,⁴ other biases might have affected the sample. Finally, IDUs were interviewed in 20 MSAs with high AIDS prevalence; findings from these cities might not be generalizable to other cities or states.

To reduce the number of new HIV infections, the National HIV/AIDS Strategy^†† calls for intensifying prevention efforts in communities where HIV is most heavily concentrated. CDC's high impact prevention approach^§§ is an essential step toward achieving the goals of the national strategy. HIV prevention strategies for IDUs, including HIV testing and linkage to care, prevention and care for HIV-infected IDUs, and access to new sterile syringes,^¶¶ have been shown to be effective. Targeted, effective approaches to HIV prevention will help reduce the number of new HIV infections among IDUs.

Acknowledgments

National HIV Behavioral Surveillance System staff members, including Jennifer Taussig, Laura Salazar, Shacara Johnson, Jeff Todd, Atlanta, Georgia; Colin Flynn, Danielle German, Baltimore, Maryland; Debbie Isenberg, Maura Driscoll, Elizabeth Hurwitz, Boston, Massachusetts; Nik Prachand, Nanette Benbow, Chicago, Illinois; Sharon Melville, Richard Yeager, Jim Dyer, Alicia Novoa, Dallas, Texas; Mark Thrun, Alia Al-Tayyib, Denver, Colorado; Emily Higgins, Eve Mokotoff, Detroit, Michigan; Aaron Sayegh, Jan Risser, Hafeez Rehman, Houston, Texas; Trista Bingham, Ekow Sey, Los Angeles, California; Lisa Metsch, Dano Beck, David Forrest, Gabriel Cardenas, Miami, Florida; Chris Nemeth, Lou Smith, Carol-Ann Watson, Nassau-Suffolk, New York; William Robinson, DeAnn Gruber, Narquis Barak, New Orleans, Louisiana; Alan Neaigus, Sam Jenness, Travis Wendel, Camila Gelpi-Acosta, New York, New York; Henry Godette, Barbara Bolden, Sally D'Errico, Newark, New Jersey; Kathleen Brady, Althea Kirkland, Mark Shpaner, Philadelphia, Pennsylvania; Vanessa Miguelino-Keasling, Al Velasco, San Diego, California; Henry Raymond, San Francisco, California; Sandra Miranda De León, Yadira Rolón-Colón, San Juan, Puerto Rico; Maria Courogen, Hanne Thiede, Nadine Snyder, Richard Burt, Seattle, Washington; and Tiffany West-Ojo, Manya Magnus, Irene Kuo, District of Columbia.

References

1. CDC. Diagnoses of HIV infection and AIDS in the United States: HIV surveillance report, Vol. 21. Atlanta, GA: US Department of Health and Human Services, CDC; 2011. Accessed February 24, 2012.
2. Prejean J, Song R, Hernandez A, et al. Estimated HIV incidence in the United States, 2006-2009. Plos One 2011;6:e17502.
3. Lansky A, Abdul-Quader AS, Cribbin M, et al. Developing an HIV behavioral surveillance system for injecting drug users: the National HIV Behavioral Surveillance System. Public Health Rep 2007;122(Suppl 1):48-55.
4. Salganik MJ, Heckathorn DD. Sampling and estimation in hidden populations using respondent-driven sampling. Sociol Method 2004;34:193-240.
5. Brady JE, Friedman SR, Cooper HL, Flom PL, Tempalski B, Gostnell K. Estimating the prevalence of injection drug users in the U.S. and in large U.S. metropolitan areas from 1992 to 2002. J Urban Health 2008;85:323-51.
6. CDC. HIV prevalence trends in selected populations in the United States: results from national serosurveillance, 1993-1997. Atlanta, GA: US Department of Health and Human Services, CDC; 2001. Accessed February 24, 2012.
7. CDC. HIV-associated behaviors among injecting-drug users -- 23 cities, United States, May 2005-February 2006. MMWR 2009;58:329-32.
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* The 20 MSAs were Atlanta, Georgia; Baltimore, Maryland; Boston, Massachusetts; Chicago, Illinois; Dallas, Texas; Denver, Colorado; Detroit, Michigan; Houston, Texas; Los Angeles, California; Miami, Florida; Nassau-Suffolk, New York; New Orleans, Louisiana; New York, New York; Newark, New Jersey; Philadelphia, Pennsylvania; San Diego, California; San Francisco, California; San Juan, Puerto Rico; Seattle, Washington; and Washington, District of Columbia.

† The incentive format (cash or gift card) and amount varied by MSA based on formative assessment and local policy. A typical format included $25 for completing the interview, $25 for providing a specimen for HIV testing, and $10 for each successful recruitment (maximum of five).

§ Sharing syringes was defined as "using needles that someone else had already injected with." Sharing injection equipment was defined as using cookers, cottons, or water to rinse needles or prepare drugs "that someone else had already used." Unprotected vaginal and anal sex were defined as "sex without a condom." Male-male anal sex was restricted to males and includes both insertive and receptive anal sex. Participating in an individual or group HIV behavioral intervention (e.g., a one-on-one conversation with a counselor or an organized discussion regarding HIV prevention) did not include counseling received as part of an HIV test. Testing for HCV infection was measured as ever tested or ever received a diagnosis of hepatitis C.

¶ City-level estimates with inadequate sample size for analysis (five or fewer observations) were excluded from aggregation. For city-level estimates for which confidence intervals could not be calculated, maximally wide confidence intervals (0-1) were used in aggregation. Such estimates represented <4% of the analysis.

** Data from 426 participants were excluded because of missing recruitment data (five participants), lost data during electronic upload (142), incomplete survey data (25), survey responses with questionable validity (63), invalid HIV test results (130), could not be identified as male or female (53), or other reason (eight). Reasons for exclusion were not mutually exclusive and were applied hierarchically in the order listed.

†† Additional information available at www.whitehouse.gov/administration/eop/onap/nhas.

§§ Additional information available at www.cdc.gov/hiv/strategy.

¶¶ In December 2011, Congress reinstated a ban on the use of federal funds for carrying out any program of distributing sterile needles or syringes for hypodermic injection of illegal drugs.