Past-Year HIV Testing, Current Antiretroviral Therapy Use, and Participation in Services for People Who Inject Drugs.

Evaluating routine HIV testing and treatment and use of services for people who inject drugs (PWID) is critical to curb the ongoing HIV epidemic. We analyzed data from the 2018 National HIV Behavioral Surveillance of PWID aged 18 years or older, recruited using respondent-driven sampling and offered anonymous HIV testing after survey. We performed bivariate and multivariable analyses with log-linked Poisson regression of the generalized linear models to examine the associations between demographics and PWID service use, past-year HIV testing, and current antiretroviral therapy (ART) use. Among 10,311 HIV-negative PWID, 56% reported past-year HIV testing, and of the 553 HIV-positive PWID, 69% reported current ART use. Of the HIV-negative PWID, 64% (2874/4482) in drug treatment and 62% (3386/5440) who used syringe service programs (SSPs) reported past-year HIV testing. Among HIV-positive PWID, 75% (187/248) in drug treatment and 67% (200/298) SSP participants were on ART. In the adjusted multivariable model, past-year HIV testing was associated with drug use treatment (aPR 1.26, 95% CI 1.23-1.31) and SSP participation (aPR 1.19, 95% CI 1.13-1.26) among HIV-negative PWID. Current ART use was associated with drug use treatment (aPR 1.13, 95% CI 1.00-1.28) but the link was not significant probably due to small sample size. Findings support the expansion and improvement of PWID-targeted services, into comprehensive programs, including drug use treatment, SSP, and HIV testing and treatment.

HIV Infection and HIV-Associated Behaviors Among Persons Who Inject Drugs - 23 Metropolitan Statistical Areas, United States, 2018.

In the United States, 10% of HIV infections diagnosed in 2018 were attributed to unsafe injection drug use or male-to-male sexual contact among persons who inject drugs (PWID) (1). In 2017, among PWID or men who have sex with men and who inject drugs (MSM-ID), 76% of those who received a diagnosis of HIV infection lived in urban areas* (2). To monitor the prevalence of HIV infection and associated behaviors among persons who reported injecting drugs in the past 12 months, including MSM-ID, CDC's National HIV Behavioral Surveillance (NHBS) conducts interviews and HIV testing among populations of persons at high risk for HIV infection (MSM, PWID, and heterosexually active adults at increased risk for HIV infection) in selected metropolitan statistical areas (MSAs) (3). The estimated HIV infection prevalence among PWID in 23 MSAs surveyed in 2018 was 7%. Among HIV-negative PWID, an estimated 26% receptively shared syringes and 68% had condomless vaginal sex during the preceding 12 months. During the same period, 57% had been tested for HIV infection, and 55% received syringes from a syringe services program (SSP). While overall SSP use did not significantly change since 2015, a substantial decrease in SSP use occurred among Black PWID, and HIV prevalence among Black PWID was higher than that among Hispanic and White PWID. These findings underscore the importance of continuing and expanding HIV prevention programs and community-based strategies for PWID, such as those provided by SSPs, especially following service disruptions created by the COVID-19 pandemic (4). Efforts are needed to ensure that PWID have low-barrier access to comprehensive and integrated needs-based SSPs (where legally permissible) that include provision of sterile syringes and safe syringe disposal, HIV and hepatitis C virus (HCV) testing and referrals to HIV and HCV treatment, HIV preexposure prophylaxis, and treatment for substance use and mental health disorders.

Using Search Engine Data to Explore Interest in PrEP and HIV Testing in the United States.

We used Google search data from January 1, 2014 to January 1, 2019 to explore public awareness of pre-exposure prophylaxis (PrEP) and HIV testing in the United States. Using two search strings, one for PrEP and one for HIV testing, we compared search volume to state HIV prevalence and new HIV diagnoses. We also used Google News to identify news events related to short-term spikes in search volume. Controlling for poverty, education, and internet access, a one-unit increase in a state's HIV prevalence rate was associated with a 3% increase in PrEP search volume (aPR = 1.03 [1.034, 1.037], P < 0.0001) and HIV testing search volume (aPR = 1.03 [1.030, 1.032], P < 0.0001). Short-term search volume spikes also coincided with celebrity news and pharmaceutical company advertising. We demonstrate that search engine data can be a powerful tool for understanding HIV knowledge-seeking and can provide key insight to the events that drive public interest about HIV online.

RESUMEN: Usamos datos de búsqueda de Google desde el 1 de enero de 2014 hasta el 1 de enero de 2019 para explorar la conciencia pública sobre la profilaxis previa a la exposición (PrEP) y las pruebas del VIH en los Estados Unidos. Utilizando dos cadenas de búsqueda, una para PrEP y otra para pruebas de VIH, comparamos el volumen de búsqueda con la prevalencia del VIH estatal y los nuevos diagnósticos de VIH. También usamos Google News para identificar eventos de noticias relacionados con picos a corto plazo en el volumen de búsqueda. Al controlar la pobreza, la educación y el acceso a Internet, un aumento de una unidad en la tasa de prevalencia del VIH de un estado se asoció con un aumento del 3% en el volumen de búsqueda de PrEP (aPR = 1.03 [1.034, 1.037], P <0.0001) y la búsqueda de pruebas de VIH volumen (aPR = 1.03 [1.030, 1.032], P <0.0001). Los picos de volumen de búsqueda a corto plazo también coincidieron con noticias de celebridades y publicidad de compañías farmacéuticas. Demostramos que los datos de los motores de búsqueda pueden ser una herramienta poderosa para comprender la búsqueda de conocimientos sobre el VIH y pueden proporcionar información clave sobre los eventos que generan el interés público sobre el VIH en línea.

Injection Practices and Sexual Behaviors Among Persons with Diagnosed HIV Infection Who Inject Drugs - United States, 2015-2017.

During 2016, 6% of persons in the United States who received a diagnosis of human immunodeficiency virus (HIV) infection had their HIV infection attributed to injection drug use (1). Injection practices and sexual behaviors among HIV-positive persons who inject drugs, such as injection equipment sharing and condomless sex, can increase HIV transmission risk; nationally representative estimates of the prevalences of these behaviors are lacking. The Medical Monitoring Project (MMP) is an annual, cross-sectional survey that reports nationally representative estimates of clinical and behavioral characteristics among U.S. adults with diagnosed HIV (2). CDC used MMP data to assess high-risk injection practices and sexual behaviors among HIV-positive persons who injected drugs during the preceding 12 months and compared their HIV transmission risk behaviors with those of HIV-positive persons who did not inject drugs. During 2015-2017, approximately 10% (weighted percentage estimate) of HIV-positive persons who injected drugs engaged in distributive injection equipment sharing (giving used equipment to another person for use); nonsterile syringe acquisition and unsafe disposal methods were common. Overall, among HIV-positive persons who injected drugs, 80% received no treatment, and 57% self-reported needing drug or alcohol treatment. Compared with HIV-positive persons who did not inject drugs, those who injected drugs were more likely to have a detectable viral load (48% versus 35%; p = 0.008) and engage in high-risk sexual behaviors (p<0.001). Focusing on interventions that reduce high-risk injection practices and sexual behaviors and increase rates of viral suppression might decrease HIV transmission risk among HIV-positive persons who inject drugs. Successful substance use treatment could also lower risk for transmission and overdose through reduced injection.

Distributive Syringe Sharing and Use of Syringe Services Programs (SSPs) Among Persons Who Inject Drugs.

Monitoring distributive syringe sharing (DSS) and syringe services program (SSP) use among persons who inject drugs (PWID) is important for HIV prevention. PWID aged ≥ 18 in 20 US cities were recruited for National HIV Behavioral Surveillance in 2015 using respondent-driven sampling, interviewed and offered HIV testing. Bivariate and multivariable analyses via log-linked Poisson regression with generalized estimating equations were conducted to examine associations between demographic and behavioral variables and DSS. Effect of SSP use on DSS by HIV sero-status was assessed by including an interaction between SSP and sero-status. Analyses were adjusted for sampling design. Among 10,402 PWID, 42% reported DSS. DSS was less likely to be reported among HIV-positive compared to HIV-negative PWID (aPR = 0.51, CI 0.45-0.60), and among those who primarily obtained syringes from SSPs versus those who did not (aPR = 0.82, 95% CI 0.77-0.88). After adjustment, those who primarily used SSPs were less likely to report DSS than those who did not among both HIV-negative PWID (aPR = 0.84, 95% CI 0.78-0.90) and HIV-positive PWID (aPR = 0.54, 95% CI 0.39-0.75). Findings support expansion of SSPs, and referrals to SSPs by providers working with PWID.

Changes in Reported Injection Behaviors Following the Public Health Response to an HIV Outbreak Among People Who Inject Drugs: Indiana, 2016.

A syringe services program (SSP) was established following the Indiana HIV outbreak among persons who inject drugs (PWID) in Scott County. Among Indiana-based PWID, we examined injection behaviors associated with HIV status, SSP use after its establishment, and changes in injection behaviors after the outbreak response. During 2016, we interviewed 200 PWID and assessed injection behaviors before the response by HIV status. We reported injection behaviors prior to the response and used Fisher's exact Chi square tests (P < 0.05) to assess differences by HIV status. Next, among persons who injected both before (July-December 2014) and after (past 30 days) the response, we (1) reported the proportion of persons who used the SSP to obtain sterile syringes, and assessed differences in SSP use by HIV status using Fisher's exact Chi square tests; and (2) compared distributive and receptive sharing of injection equipment and disposal of syringes before and after the outbreak response, and assessed statistical differences using McNemar's test. We also compared injection behaviors before and after the response by HIV status. Injecting extended release oxymorphone (Opana® ER); receptive sharing of syringes and cookers; and distributive sharing of cookers, filters, or water before the response were associated with HIV infection. SSP use was high (86%), particularly among HIV-positive compared with HIV-negative persons (98% vs. 84%). Injection equipment sharing decreased and safe disposal of used syringes increased after the response, especially among HIV-positive persons. Injection equipment sharing contributed to the outbreak. High SSP use following the response, particularly among HIV-positive persons, contributed to decreased high-risk injection practices.

HIV Infection and HIV-Associated Behaviors Among Persons Who Inject Drugs - 20 Cities, United States, 2015.

In the United States, 9% of human immunodeficiency virus (HIV) infections diagnosed in 2015 were attributed to injection drug use (1). In 2015, 79% of diagnoses of HIV infection among persons who inject drugs occurred in urban areas (2). To monitor the prevalence of HIV infection and associated behaviors among persons who inject drugs, CDC's National HIV Behavioral Surveillance (NHBS) conducts interviews and HIV testing in selected metropolitan statistical areas (MSAs) (3). The prevalence of HIV infection among persons who inject drugs in 20 MSAs in 2015 was 7%. In a behavioral analysis of HIV-negative persons who inject drugs, an estimated 27% receptively shared syringes and 67% had condomless vaginal sex in the previous 12 months. During the same period, 58% had tested for HIV infection and 52% received syringes from a syringe services program. Given the increased number of persons newly injecting drugs who are at risk for HIV infection because of the recent opioid epidemic (2,4), these findings underscore the importance of continuing and expanding health services, HIV prevention programs, and community-based strategies, such as those provided by syringe services programs, for this population.

Associations of HIV Testing, Sexual Risk and Access to Prevention Among Female Sex Workers in the Dominican Republic.

The Caribbean region has one of the highest proportions of HIV in the general female population attributable to sex work. In 2008 (n = 1256) and 2012 (n = 1525) in the Dominican Republic, HIV biological and behavioral surveys were conducted among female sex workers (FSW) in four provinces using respondent driven sampling. Participants were ≥15 years who engaged in intercourse in exchange for money in the past 6 months and living/working in the study province. There were no statistically significant changes in HIV and other infections prevalence from 2008 to 2012, despite ongoing risky sexual practices. HIV testing and receiving results was low in all provinces. FSW in 2012 were more likely to receive HIV testing and results if they participated in HIV related information and education and had regular checkups at health centers. Further investigation is needed to understand barriers to HIV testing and access to prevention services.

A Systematic Review of Published Respondent-Driven Sampling Surveys Collecting Behavioral and Biologic Data.

Reporting key details of respondent-driven sampling (RDS) survey implementation and analysis is essential for assessing the quality of RDS surveys. RDS is both a recruitment and analytic method and, as such, it is important to adequately describe both aspects in publications. We extracted data from peer-reviewed literature published through September, 2013 that reported collected biological specimens using RDS. We identified 151 eligible peer-reviewed articles describing 222 surveys conducted in seven regions throughout the world. Most published surveys reported basic implementation information such as survey city, country, year, population sampled, interview method, and final sample size. However, many surveys did not report essential methodological and analytical information for assessing RDS survey quality, including number of recruitment sites, seeds at start and end, maximum number of waves, and whether data were adjusted for network size. Understanding the quality of data collection and analysis in RDS is useful for effectively planning public health service delivery and funding priorities.

Changes in HIV Pre-exposure Prophylaxis Awareness and Use Among Males Who Inject Drugs Who Have Sex with Men by Sexual Identity, 19 US Urban Areas, 2018 & 2022.

BACKGROUND: Men who inject drugs who have sex with men (MWIDSM) may acquire HIV through injecting drugs or sex. Interventions to increase awareness of HIV preexposure prophylaxis (PrEP) have focused on gay/bisexual MSM and may not be reaching heterosexual-identifying men or people who inject drugs (PWID). We explored changes in PrEP awareness and use among MWIDSM from 2018 to 2022 by sexual identity. METHODS: We used data from the 2018 and 2022 National HIV Behavioral Surveillance among PWID recruited via respondent-driven sampling in 19 urban areas in the US. We examined changes in PrEP awareness and use over time by sexual identity among HIV-negative men who inject drugs and who had sex with another man in the past 12 months using log-linked Poisson regression models with robust standard errors with an interaction term between year and sexual identity. RESULTS: Among 758 HIV-negative MWIDSM (463 in 2018; 295 in 2022), nearly all sample participants were likely indicated for PrEP (94.2 and 92.9%, respectively). PrEP awareness increased from 2018 to 2022 among gay/bisexual-identifying MWIDSM [45.5-65.5%; aPR = 1.49, 95% confidence interval (95% CI) = 1.30-1.70] but remained stable for heterosexual-identifying MWIDSM (39.4-40.8%; aPR = 1.01, 95% CI 0.75-1.36). PrEP use remained low among all MWIDSM (2.5-7.7%, among heterosexually identifying; 15.3 to 10.2% among gay/bisexual-identifying). CONCLUSION: PrEP awareness increased among gay/bisexual-identifying MWIDSM but not among heterosexual-identifying. PrEP use was low for all MWIDSM. Public health initiatives catered to MWIDSM should focus on improved campaigns and expanding PrEP accessibility in existing healthcare, harm reduction, and social services.

Intersecting structural and psychosocial conditions: investigating injection drug use and HIV among transgender women.

BACKGROUND: Transgender women continue to face a significant burden of health disparities with HIV infection as a critical public health concern. Substance use is higher among transgender women compared to cisgender women. However, little is known about transgender women who inject drugs and risk for HIV in the United States. The objectives were to explore HIV prevalence, injection-related behaviors, and HIV prevention and care outcomes among transgender women who inject drugs and to compare transgender women to a general sample of people who inject drugs (PWID). METHODS: Participants from National HIV Behavioral Surveillance were recruited via respondent-driven sampling, interviewed, and tested for HIV infection in 2019-2020. Log-linked Poisson regression models were used to test for associations between injection drug use and selected characteristics. RESULTS: Among 1,561 transgender women, 7% injected drugs in the past 12 months. HIV prevalence was higher among transgender women who inject (aPR=1.5, 95%CI=1.2-1.8) than those who do not. Multiple psychosocial conditions were associated with injection drug use. Among transgender women with HIV, those who inject were less likely to take antiretroviral therapy (aPR=0.8, 95%CI=0.7-1.0) than those who do not. Methamphetamine was the most commonly injected drug (67%); most accessed a syringe services program (66%). CONCLUSION: Transgender women who inject have substantial challenges related to health outcomes including high HIV prevalence and exposure to psychosocial conditions, such as homelessness, incarceration, and exchange sex, that may exacerbate risks associated with injection drug use. This population may benefit from increased access to non-judgmental and culturally competent harm reduction services.

Using serial cross-sectional surveys to create a retrospective nested cohort to determine HIV incidence from 20 US cities.

OBJECTIVE: To estimate HIV incidence using successive cross-sectional surveys by creating retrospective nested cohorts among MSM, people who inject drugs (PWID), and heterosexually active persons (HET). DESIGN: Cohorts were created among participants who had at least one repeat observation across four surveillance cycles from National HIV Behavioral Surveillance in 20 US cities. METHODS: Repeat participants were identified using a combination of date of birth, race/ethnicity, metropolitan statistical area, and gender. The analysis was limited to participants who tested negative for HIV at baseline and were assumed to be at risk between cycles. We calculated person-years at risk from the individual time between cycles and used the total number of seroconversions to estimate incidence and a Poisson distribution to approximate variance. Rate ratios were calculated using age, gender, race/ethnicity, and region. RESULTS: From 2008 to 2019, successive surveys recaptured nested cohorts of 1747 MSM, 3708 PWID, and 1396 HET. We observed an incidence rate of 2.5 per 100 person-years [95% confidence interval (CI) 2.1-2.8) among MSM; 0.6 per 100 person-years (95% CI 0.5-0.7) among PWID; and 0.3 per 100 person-years (95% CI 0.1-0.4) among HET. HIV incidence was higher among younger MSM, black MSM (compared with white MSM), and PWID residing in the South and territories (compared with the Midwest). CONCLUSION: These estimates are consistent with previously published incidence estimates from prospective cohort studies among these populations. Using repeat cross-sectional surveys to simulate a cohort, may serve as another strategy in estimating HIV incidence.

COVID-19 Burden in Adult Correctional or Detention Facilities and the Surrounding Communities, January 1, 2020-July 20, 2021.

We estimated the COVID-19 burden in adult correctional or detention facilities and associated counties by state, facility jurisdiction, and county urbanicity. COVID-19 cumulative incidence (cases per 1,000 persons) for each U.S. correctional or detention facility and people ages 18 years and older in the associated county was estimated between January 1, 2020 and July 20, 2021. Across 46 U.S. states, 1,083 correctional or detention facilities in 718 counties were included. The median COVID-19 incidence rate was higher in facilities than in associated counties for 42 of 46 states and for all facility jurisdictions and county urbanicity categories. COVID-19 burden was higher in most facilities than in associated counties. Implementing COVID-19 mitigation measures in correctional settings is needed to prevent SARS-CoV-2 transmission in facilities and associated counties.

Opportunities for Closing the Gap in HIV Diagnosis, Treatment, and Viral Load Suppression in Children in Malawi: Results From a 2015-2016 Population-based HIV Impact Assessment Survey.

BACKGROUND: Control of the pediatric HIV epidemic is hampered by gaps in diagnosis and linkage to effective treatment. The 2015-2016 Malawi Population-based HIV impact assessment data were analyzed to identify gaps in pediatric HIV diagnosis, treatment, and viral load suppression. METHODS: In half of the surveyed households, children ages ≥18 months to <15 years were tested using the national HIV rapid test algorithm. Children ≤18 months reactive by the initial rapid test underwent HIV total nucleic acid polymerase chain reaction confirmatory testing. Blood from HIV-positive children was tested for viral load (VL) and presence of antiretroviral drugs. HIV diagnosis and antiretroviral treatment (ART) use were defined using guardian-reporting or antiretroviral detection. RESULTS: Of the 6166 children tested, 99 were HIV-positive for a prevalence of 1.5% (95% confidence intervals [CI]: 1.1-1.9) and 8.0% (95% CI: 5.6-10.5) among HIV-exposed children. The prevalence of 1.5% was extrapolated to a national estimate of 119,501 (95% CI: 89,028-149,974) children living with HIV (CLHIV), of whom, 30.7% (95% CI: 20.3-41.1) were previously undiagnosed. Of the 69.3% diagnosed CLHIV, 86.1% (95% CI: 76.8-95.6) were on ART and 57.9% (95% CI: 41.4-74.4) of those on ART had suppressed VL (<1000 HIV RNA copies/mL). Among all CLHIV, irrespective of HIV diagnosis or ART use, 57.7% (95% CI: 45.0-70.5) had unsuppressed VL. CONCLUSIONS: Critical gaps in HIV diagnosis in children persist in Malawi. The large proportion of CLHIV with unsuppressed VL reflects gaps in diagnosis and need for more effective first- and second-line ART regimens and adherence interventions.

Population-Based HIV Impact Assessments Survey Methods, Response, and Quality in Zimbabwe, Malawi, and Zambia.

BACKGROUND: The population-based HIV impact assessment (population-based HIV impact assessments) surveys are among the first to estimate national adult HIV incidence, subnational prevalence of viral load suppression, and pediatric HIV prevalence. We summarize the survey methods implemented in Zimbabwe, Malawi, and Zambia, as well as response rates and quality metrics. METHODS: Each cross-sectional, household-based survey used a 2-stage cluster design. Survey preparations included sample design, questionnaire development, tablet programming for informed consent and data collection, community mobilization, establishing a network of satellite laboratories, and fieldworker training. Interviewers collected demographic, behavioral, and clinical information using tablets. Blood was collected for home-based HIV testing and counseling (HBTC) and point-of-care CD4+ T-cell enumeration with results immediately returned. HIV-positive blood samples underwent laboratory-based confirmatory testing, HIV incidence testing, RNA polymerase chain reaction (viral load), DNA polymerase chain reaction (early infant diagnosis), and serum antiretroviral drug detection. Data were weighted for survey design, and chi square automatic interaction detection-based methods were used to adjust for nonresponse. RESULTS: Each survey recruited a nationally representative, household-based sample of children and adults over a 6-10-month period in 2015 and 2016. Most (84%-90%) of the 12,000-14,000 eligible households in each country participated in the survey, with 77%-81% of eligible adults completing an interview and providing blood for HIV testing. Among eligible children, 59%-73% completed HIV testing. Across the 3 surveys, 97.8% of interview data were complete and had no errors. CONCLUSION: Conducting a national population-based HIV impact assessment with immediate return of HIV and other point-of-care test results was feasible, and data quality was high.

Distance matters: The association of proximity to syringe services programs with sharing of syringes and injecting equipment - 17 U.S. cities, 2015.

BACKGROUND: Syringe services programs (SSPs) have effectively limited the spread of HIV and hepatitis C (HCV) among people who inject drugs (PWID). Access to SSPs has been shown to reduce injection risk behaviors but the relationship between distance to an SSP and likelihood of sharing injection equipment is not well known. METHODS: We analyzed a sample of 8,392 PWID from 17 U.S. cities recruited through the National HIV Behavioral Surveillance (NHBS) system in 2015. Adjusted prevalence ratios (aPR) and 95% confidence intervals (CI) were estimated from log-linked Poisson regression to explore associations between injecting equipment sharing in the past 12 months and distance to the nearest SSP. RESULTS: Regardless of SSP use, respondents who lived in zip codes further than the city-specific mean distance to nearest SSP were more likely to report sharing behavior. Among PWID who had not reported using an SSP in the previous 12 months, distributive sharing (aPR=1.13 95% CI=1.05, 1.21), receptive sharing (aPR=1.15, 95% CI=1.06, 1.24), and injection equipment sharing (aPR=1.08, 95% CI=1.03, 1.13) were more prevalent among residents who resided further than the average distance to the nearest SSP. CONCLUSIONS: Greater distance to an SSP was associated with increased sharing behaviors. Improved access to an SSP and subsequent decreases in sharing behaviors could reduce transmission of HIV and HCV among PWID. Accessibility should be taken into account when planning provision of SSPs.

Human papillomavirus vaccination coverage among men who have sex with men-National HIV Behavioral Surveillance, United States, 2017.

Men who have sex with men (MSM) are at high risk for infections and diseases caused by human papillomavirus (HPV), many of which are vaccine-preventable. In the United States, routine HPV vaccination has been recommended for adolescent males since 2011. This analysis evaluated self-reported receipt of ≥ 1 HPV vaccine dose by age group and HIV status among adult MSM using 2017 data from National HIV Behavioral Surveillance (NHBS) and compared the proportion vaccinated to prior years. Among 10,381 MSM aged ≥ 18 years, 17.9% of MSM overall and 28.4% of MSM living with HIV reported any HPV vaccination. Among 2,482 MSM aged 18-26 years, 32.8% overall and 51.3% living with HIV reported HPV vaccination. Since 2011, the proportion of MSM aged 18-26 years reporting HPV vaccination has increased over six-fold. As vaccinated adolescents age into young adults, coverage will continue to increase overall, including among MSM.

Defining and surveying key populations at risk of HIV infection: Towards a unified approach to eligibility criteria for respondent-driven sampling HIV biobehavioral surveys.

Substantial resources are invested in human immunodeficiency virus biobehavioral surveys using respondent-driven sampling for measuring progress towards the UNAIDS 90-90-90 goals and to obtain other essential data on key populations. Survey data are used to meet country needs as well those of development partners, whose data needs may sometimes diverge. Surveys using differing eligibility criteria impede comparisons across surveys. With scant literature and guidelines on how to approach eligibility criteria, diverse criteria are used within and across countries. We conducted a review of peer-reviewed human immunodeficiency virus respondent-driven sampling biobehavioral survey literature published through December 2013. We describe eligibility criteria of 137 articles representing 214 surveys. Reporting on age, risk behavior, and reference period of risk behavior was nearly universal; however, reporting on gender, geography, and language was less common. Multiple definitions were used for each criterion, making comparisons challenging. We provide a framework for how to approach defining eligibility to improve consistency and comparability across surveys.

Gaps and opportunities: measuring the key population cascade through surveys and services to guide the HIV response.

INTRODUCTION: The UNAIDS 90-90-90 targets to diagnose 90% of people living with HIV, put 90% of them on treatment, and for 90% of them to have suppressed viral load have focused the international HIV response on the goal of eliminating HIV by 2030. They are also a constructive tool for measuring progress toward reaching this goal but their utility is dependent upon data availability. Though more than 25% of new infections are among key populations (KP)- sex workers, men who have sex with men, transgender people, people who inject drugs, and prisoners- and their sex partners, there is a dearth of treatment cascade data for KP. We assess the availability of cascade data and review the opportunities offered by biobehavioral and programme data to inform the HIV response. DISCUSSION: The emphasis on the collection of treatment cascade data among the general population in higher prevalence countries has not led to a similar increase in the availability of cascade data for KP. The limited data available for KP highlight large gaps in service uptake across the cascade, particularly in the first 90, awareness of HIV status. Biobehavioral surveys (BBS), with linked population size estimation, provide population-based data on the treatment cascade and should be conducted every two to three years in locations with services for KP. With the inclusion of viral load testing, these surveys are able to monitor the entire treatment cascade among KP regardless of whether these populations access HIV services targeting the general population or KP. BBS also reach people accessing services and those who do not, thereby providing a unique opportunity to learn about barriers to service uptake including stigma and discrimination. At the same time high-quality programme data can play a complementary role in identifying missed opportunities that can be addressed in real-time. CONCLUSIONS: Data are more important than ever for guiding the HIV response toward reaching 90-90-90 targets and eliminating HIV, particularly in the face of decreased funding for HIV and specifically for KP. Timely high-quality BBS data can be triangulated with high-quality programme data to provide a comprehensive picture of the epidemic response for KP.