National HIV Behavioral Surveillance (NHBS)

About national HIV behavioral surveillance

In 2003, CDC created NHBS to conduct bio-behavioral surveillance among populations disproportionately affected by HIV.

Surveillance is conducted in rotating, annual cycles in three different populations:

1. Gay, bisexual and other men who have sex with men; known as the MSM cycle. The NHBS-MSM cycle collects information on persons who report sex with a male partner in the 12 months before interview.

2. Persons who inject drugs; known as the PWID cycle. The NHBS-PWID cycle collects information on persons who report injecting a drug that was not prescribed for them in the 12 months before interview.

3. Heterosexually active persons at increased risk for HIV infection; known as the HET cycle. The NHBS-HET cycle collects information on heterosexually active persons at increased risk for HIV^* reporting sex with an opposite sex partner in the 12 months before interview.

These three annual cycles are considered a round.

In addition to the three core cycles, a limited number of project areas conducted surveys with women of trans experience and transfeminine people (NHBS-Trans). The NHBS-Trans focuses on women of trans experience and transfeminine people (WTE/TFP) especially WTE/TFP of color, who are disproportionately affected by HIV.

_{*NHBS uses low income as a proxy for increased risk for acquiring HIV through heterosexual sex.}

Lab collaborations

In addition to the HIV test offered as part of NHBS, project areas may conduct other tests with local funds if local regulations permit anonymous testing. Further, CDC's Division of HIV Prevention (DHP) collaborates with other agencies and CDC divisions to fund additional biological testing as part of NHBS.

Project areas

Currently (2023-2026), 19 project areas with high prevalence of HIV conduct NHBS. Many of the state health department recipients collaborate with local health departments, universities, or community-based organizations to implement NHBS activities. Several of the project areas also participate in conducting NHBS among additional populations and in collaborations to provide additional biological testing as part of NHBS.

What's collected

NHBS-MSM/PWID/HET

NHBS collects data on behavioral risk factors for HIV (e.g., sexual behaviors, drug use), HIV testing behaviors, the receipt of prevention services, and use of prevention strategies (e.g., condoms, PrEP). In addition to these interview data, all NHBS participants are offered an HIV test regardless of their self-reported HIV status.

NHBS-Trans

A limited number of project areas have conducted surveys with transgender women. NHBS-Trans data are collected to assess HIV prevalence and associated behaviors and other experiences important to the health and well-being of transgender women, especially transgender women of color.

How information is collected

• Before each NHBS cycle, formative assessment is conducted to learn more about each local population and to inform operational procedures.
• Venue-based, time-space sampling (VBS) is used during the MSM cycles.
  • Project area staff identify venues frequented by MSM (e.g., bars, clubs, organizations, and street locations) as well as days/times when men frequent those venues.
  • Venues (and specific day/time periods) for recruitment are chosen randomly each month.

• Respondent-driven sampling (RDS) is used during the PWID and HET cycles.
  • Project area staff select a small number of initial participants, or "seeds," who complete the survey and recruit their peers to participate.
• Recruitment and interviewing then continue until the target sample size is reached.
• Trained interviewers in all NHBS project areas use a standardized, anonymous questionnaire to collect information on HIV-related risk behaviors, HIV testing, and the use of HIV prevention services.
• HIV testing is offered to all participants regardless of their self-reported HIV status.
• During each cycle, a minimum of 500 eligible persons from each participating project area are interviewed and offered HIV testing.

How NHBS data are used

NHBS data are used to provide a behavioral context for trends seen in HIV surveillance data. They also describe populations disproportionately affected by HIV and thus provide an indication of the leading edge of the epidemic. Through systematic surveillance in these populations, NHBS is critical for monitoring the impact of the National HIV/AIDS Strategy, which focuses on decreasing HIV incidence, improving linkage to care, and reducing disparities.

Data releases

• HIV Risk, Prevention, and Testing Behaviors Among Men Who Have Sex With Men
• HIV Risk, Prevention, and Testing Behaviors Among Persons Who Inject Drugs
• HIV Risk, Prevention, and Testing Behaviors Among Heterosexually Active People
• Back Issues of Data Reports on CDC Stacks
• NCHHSTP Atlas Plus

Resources