Piloting a system for behavioral surveillance among heterosexuals at increased risk of HIV in the United States.

OBJECTIVES: During the past decade, the number and proportion of reported HIV cases in the United States acquired through heterosexual contact has increased markedly. CDC employs the National HIV Behavioral Surveillance System (NHBS) to monitor risk behaviors and HIV prevalence in high-risk populations. To identify a target population for conducting NHBS among heterosexuals at increased risk for HIV (NHBS-HET), CDC designed, implemented and evaluated a pilot study.

METHODS: The pilot study was conducted in 25 US metropolitan statistical areas in 2006-7. We recruited men and women who reported sex with at least one opposite-sex partner during the past year for a behavioral survey and HIV test. We investigated the relationship between newly diagnosed HIV infection and individual risk behaviors, sexual network characteristics, and social-structural characteristics to arrive at a definition of a heterosexual at increased risk of HIV.

RESULTS: Of 14,750 participants in the analysis, 207 (1.4%) had newly diagnosed HIV infection. Using low socioeconomic status (SES) as a criterion for defining a heterosexual at increased risk for HIV resulted in optimal rates of HIV prevalence, specificity, sensitivity and practicality.

CONCLUSIONS: Results from the NHBS pilot study underscore the key role of social factors as determinants of HIV infection risk among U.S. heterosexuals, and low SES was incorporated into the definition of a heterosexual at increased risk for HIV in NHBS-HET cycles. Future cycles of NHBS-HET will help tailor prevention programs for those populations most at risk of HIV in the US.