Mapping HIV prevalence in sub-Saharan Africa between 2000 and 2017.

HIV/AIDS is a leading cause of disease burden in sub-Saharan Africa. Existing evidence has demonstrated that there is substantial local variation in the prevalence of HIV; however, subnational variation has not been investigated at a high spatial resolution across the continent. Here we explore within-country variation at a 5 × 5-km resolution in sub-Saharan Africa by estimating the prevalence of HIV among adults (aged 15-49 years) and the corresponding number of people living with HIV from 2000 to 2017. Our analysis reveals substantial within-country variation in the prevalence of HIV throughout sub-Saharan Africa and local differences in both the direction and rate of change in HIV prevalence between 2000 and 2017, highlighting the degree to which important local differences are masked when examining trends at the country level. These fine-scale estimates of HIV prevalence across space and time provide an important tool for precisely targeting the interventions that are necessary to bringing HIV infections under control in sub-Saharan Africa.

An HIV-1 risk assessment tool for women aged 15-49 in African countries: A pooled analysis across 15 nationally representative surveys.

BACKGROUND: Women in Africa disproportionately acquire HIV-1. Understanding which women are most likely to acquire HIV-1 can guide focused prevention with pre-exposure prophylaxis (PrEP). Our objective is to identify women at highest risk of HIV-1 and estimate PrEP efficiency at different sensitivity levels. METHODS: Nationally representative data were collected from 2015-2019 from 15 population-based household surveys. This analysis included women aged 15-49 who tested HIV-1 sero-negative or had recent HIV-1. Least absolute shrinkage and selection operator regression models were fit with 28 variables to predict recent HIV-1. Models were trained on the full population and internally cross-validated. Performance was evaluated using area under the receiver-operating-characteristic curve (AUC), sensitivity, and number needed to treat (NNT) with PrEP to avert one infection. RESULTS: Among 209,012 participants 248 had recent HIV-1 infection, representing 118 million women and 402,000 (95% CI: 309,000-495,000) new annual infections. Two variables were retained in the model: living in a subnational area with high HIV-1 viremia and having a sexual partner living outside the home. Full-population AUC was 0.80 (95% CI: 0.76-0.84); cross-validated AUC was 0.79 (95% CI: 0.75-0.84). At a sensitivity of 33%, up to 130,000 cases could be averted if 7.9 million women were perfectly adherent to PrEP; NNT would be 61. At a sensitivity of 67%, up to 260,000 cases could be averted if 25.1 million women were perfectly adherent to PrEP; the NNT would be 96. CONCLUSIONS: This risk assessment tool was generalizable, predictive, and parsimonious with tradeoffs between reach and efficiency.

Prevalence of SARS-CoV-2 Infection among Children and Adults in 15 US Communities, 2021

During January-August 2021, the Community Prevalence of SARS-CoV-2 Study used time/location sampling to recruit a cross-sectional, population-based cohort to estimate SARS-CoV-2 seroprevalence and nasal swab sample PCR positivity across 15 US communities. Survey-weighted estimates of SARS-CoV-2 infection and vaccine willingness among participants at each site were compared within demographic groups by using linear regression models with inverse variance weighting. Among 22,284 persons >2 months of age and older, median prevalence of infection (prior, active, or both) was 12.9% across sites and similar across age groups. Within each site, average prevalence of infection was 3 percentage points higher for Black than White persons and average vaccine willingness was 10 percentage points lower for Black than White persons and 7 percentage points lower for Black persons than for persons in other racial groups. The higher prevalence of SARS-CoV-2 infection among groups with lower vaccine willingness highlights the disparate effect of COVID-19 and its complications.

Adaptive Time-Location Sampling for COMPASS: A SARS-CoV-2 Prevalence Study in Fifteen Diverse Communities in the United States.

BACKGROUND: COVID-19 has placed a disproportionate burden on underserved racial and ethnic groups, community members working in essential industries, those living in areas of high population density, and those reliant on in-person services such as transportation. The goal of this study was to estimate the cross-sectional prevalence of SARS-CoV-2 (active SARS-CoV-2 or prior SARS-CoV-2 infection) in children and adults attending public venues in 15 sociodemographically diverse communities in the United States and to develop a statistical design that could be rigorously implemented amidst unpredictable stay-at-home COVID-19 guidelines. METHODS: We used time-location sampling with complex sampling involving stratification, clustering of units, and unequal probabilities of selection to recruit individuals from selected communities. We safely conducted informed consent, specimen collection, and face-to-face interviews outside of public venues immediately following recruitment. RESULTS: We developed an innovative sampling design that adapted to constraints such as closure of venues, changing infection hotspots, and uncertain policies. We updated both the sampling frame and the selection probabilities over time using information acquired from prior weeks. We created site-specific survey weights that adjusted sampling probabilities for nonresponse and calibrated to county-level margins on age and sex at birth. CONCLUSIONS: Although the study itself was specific to COVID-19, the strategies presented in this article could serve as a case study that can be adapted for performing population-level inferences in similar settings and could help inform rapid and effective responses to future global public health challenges.

Feasibility and acceptability of point of care testing for sexually transmitted infections in outpatient clinics offering integrated services in Eswatini.

BACKGROUND: Lack of point of care testing (POCT) for sexually transmitted infections (STIs) is a continuing missed opportunity in Sub-Saharan Africa. We assessed feasibility and acceptability of STI POCT in Eswatini. METHODS: STI POCT for Chlamydia trachomatis (CT) and Neisseria gonorrhoea (NG) was piloted among sexually active adults 18-45 years attending two urban outpatient clinics offering HIV services. Females were randomized 1:1 to provide urine or vaginal swab and all males provided urine samples for CT/NG testing using Cepheid CT/NG cartridges on existing GeneXpert platforms. Results were returned in-person or by telephone call. We assessed duration of procedures and participant and healthcare worker acceptability of services (5-point Likert scale), time spent on STI POCT services, and correlates of CT/NG infection. RESULTS: Of 250 adults triaged, 99% (248/250) accepted STI POCT, including 44% (109/248) people living with HIV. STI POCT procedures took a median of 3:22 hours. Most adults (90%, 224/248), received results within a day (61% same day, 29% next day). CT/NG was detected among 22% (55/248): 31/55 CT, 21/55 NG and 3/55 coinfections. Youth 18-25 years, history of any sexual intercourse, and condom-less sex within the previous 7 days were significantly associated with CT/NG detected (p < 0.05). Most adults with CT/NG were treated (51/55, 93%). Most participants were satisfied with STI POCT (217/241, 90%), and would accept again/recommend it. All 32 healthcare workers who participated were satisfied with STI POCT. CONCLUSION: STI POCT was feasible, acceptable, and identified a high prevalence of STIs, highlighting the urgent need for this testing.

Age-disparate and intergenerational sex partnerships and HIV: the role of gender norms among adolescent girls and young women in Malawi.

BACKGROUND: Age-mixing (age-disparate [5-9 years difference] and intergenerational [≥ 10 years difference]) partnerships are hypothesized drivers of HIV in adolescent girls and young women (AGYW; 15-24 years). These partnerships are often associated with increased gender inequities which undermine women's agency and assertiveness. We assessed whether age-mixing partnerships were associated with HIV in Malawi and if endorsement of inequitable gender norms modifies this relationship. METHODS: We analyzed data from the Malawi Population-based HIV Impact Assessment, a nationally representative household survey conducted in 2015-2016. Participants underwent HIV testing and completed questionnaires related to actively endorsed gender norms and sexual risk behavior. We used multivariate logistic regression and multiplicative interaction to assess associations among AGYW who reported the age of their primary sex partner from the last year. RESULTS: The analysis included 1,958 AGYW (mean age = 19.9 years, SD = 0.1), 459 (23.4%) and 131 (6.7%) of whom reported age-disparate and intergenerational partnerships, respectively. AGYW in age-mixing partnerships accounted for 13% of all AGYW and were older, more likely to reside in urban areas, to be married or cohabitating with a partner, and to have engaged in riskier sexual behavior compared with AGYW in age-concordant partnerships (p < 0.05). HIV prevalence among AGYW in age-disparate and intergenerational partnerships was 6.1% and 11.9%, respectively, compared with 3.2% in age-concordant partnerships (p < 0.001). After adjusting for residence, age, education, employment, wealth quintile, and ever been married or cohabitated as married, AGYW in age-disparate and intergenerational partnerships had 1.9 (95% CI: 1.1-3.5) and 3.4 (95% CI: 1.6-7.2) greater odds of HIV, respectively, compared with AGYW in age-concordant partnerships. Among the 614 (31% of the study group) who endorsed inequitable gender norms, AGYW in age-disparate and intergenerational partnerships had 3.5 (95% CI: 1.1-11.8) and 6.4 (95% CI: 1.5-27.8) greater odds of HIV, respectively, compared with AGYW in age-concordant partnerships. CONCLUSIONS: In this Malawi general population survey, age-mixing partnerships were associated with increased odds of HIV among AGYW. These findings highlight inequitable gender norms as a potential focus for HIV prevention and could inform interventions targeting structural, cultural, and social constraints of this key group.

Cost-outcome analysis of HIV testing and counseling, linkage, and defaulter tracing services in Bukoba, Tanzania.

Effective services along the HIV continuum of care from HIV testing and counseling to linkage, and from linkage to antiretroviral therapy (ART) initiation and retention, are key to improved health outcomes of persons living with HIV. A comprehensive analysis of the costs and outcomes of cascade services is needed to help allocate and prioritize resources to achieve UNAIDS targets. We evaluated the costs and population-level impact of a community-wide, integrated scale-up of testing, linkage, and defaulter-tracing programs implemented in Bukoba Municipal Council, Tanzania. Costs per identified HIV-positive client for provider-initiated, and home- and venue-based testing and counseling were $92.64 United States dollars (USD), $256.33 USD, and $281.57 USD, respectively. Costs per patient linked to HIV care and ART were $47.69 USD and $74.12 USD, respectively, during all ART-eligibility periods combined. Costs per defaulter traced and returned to HIV care were $47.56 USD and $206.77 USD, respectively. The provider-initiated testing and counseling was the most cost-effective modality. Testing approaches targeted to populations groups and geographic location with high testing positivity rates may improve the overall efficiency of testing services. The expansion of ART eligibility criteria and high linkage rate also result in efficiency gains and economies of scale of linkage services.

Access to Social Protection by People Living with, at Risk of, or Affected by HIV in Eswatini, Malawi, Tanzania, and Zambia: Results from Population-Based HIV Impact Assessments.

We aimed to measure social protection coverage among the general population, women and men living with HIV (WLHIV, MLHV), female and male sex workers (FSW, MSW), men who have sex with men (MSM), adolescent girls young women (AGYW), and orphans vulnerable children (OVC) in Eswatini, Malawi, Tanzania, and Zambia. We used Population-Based HIV Impact Assessment data. We operationalised social protection benefits as external economic support from private and public sources to the household in the last three or 12 months. We estimated survey-weighted proportions and 95% confidence intervals (CI) for each population receiving social protection benefits. The sample size ranged from 10,233 adults ages 15-59 years in Eswatini to 29,638 in Tanzania. In the surveyed countries, social protection coverage among the general population was lower than the global average of 45%, ranging from 7.7% (95% CI 6.7%-8.8%) in Zambia to 39.6% (95% CI 36.8%-42.5%) in Eswatini. In Malawi and Zambia, social protection coverage among OVC, AGYW, SW, MSM, and people living with HIV (PLHIV) was similar to the general population. In Eswatini, more AGWY reported receiving social projection benefits than older women and more men not living with HIV reported receiving social protection benefits than MLHIV. In Tanzania, more WLHIV than women not living with HIV, MLHIV than men not living with HIV, and FSW than women who were not sex workers reported receiving social protection benefits. More data on access to social protection benefits by PLHIV or affected by HIV are needed to estimate better their social protection coverage.

A Longitudinal Analysis of the Impact of Health Behavior Campaigns on HIV-Risk Behaviors and HIV Incidence in Eswatini.

Between 2010 and 2015, Eswatini conducted mass media health behavior campaigns (HBCs) designed to avert new HIV infections. Using longitudinal data from the nationally representative Swaziland HIV Incidence Measurement Survey of 2011, we describe the impact of exposure to HBCs on selected HIV risk behaviors and HIV incidence among sexually active, HIV-negative adults (n = 11,232). Exposure to partner reduction HBCs was significantly associated with reporting fewer (i.e., 1 versus 2, or 2 versus ≥ 3) sexual partners in the prior 6 months at baseline among women (aOR = 3.02; 95% CI 1.38, 6.62); and at both baseline and at 6-months follow-up for men (aOR = 2.26; 95% CI 1.49, 3.44; aOR = 1.95, 95% CI [1.26-3.00], respectively). Despite these reported partner reductions, there was no association between HBC exposure and prospectively observed HIV seroconversions (n = 121). This analysis strengthens the evidence that HIV prevention at the population level requires integrated strategies.

Mapping male circumcision for HIV prevention efforts in sub-Saharan Africa.

BACKGROUND: HIV remains the largest cause of disease burden among men and women of reproductive age in sub-Saharan Africa. Voluntary medical male circumcision (VMMC) reduces the risk of female-to-male transmission of HIV by 50-60%. The World Health Organization (WHO) and Joint United Nations Programme on HIV/AIDS (UNAIDS) identified 14 priority countries for VMMC campaigns and set a coverage goal of 80% for men ages 15-49. From 2008 to 2017, over 18 million VMMCs were reported in priority countries. Nonetheless, relatively little is known about local variation in male circumcision (MC) prevalence. METHODS: We analyzed geo-located MC prevalence data from 109 household surveys using a Bayesian geostatistical modeling framework to estimate adult MC prevalence and the number of circumcised and uncircumcised men aged 15-49 in 38 countries in sub-Saharan Africa at a 5 × 5-km resolution and among first administrative level (typically provinces or states) and second administrative level (typically districts or counties) units. RESULTS: We found striking within-country and between-country variation in MC prevalence; most (12 of 14) priority countries had more than a twofold difference between their first administrative level units with the highest and lowest estimated prevalence in 2017. Although estimated national MC prevalence increased in all priority countries with the onset of VMMC campaigns, seven priority countries contained both subnational areas where estimated MC prevalence increased and areas where estimated MC prevalence decreased after the initiation of VMMC campaigns. In 2017, only three priority countries (Ethiopia, Kenya, and Tanzania) were likely to have reached the MC coverage target of 80% at the national level, and no priority country was likely to have reached this goal in all subnational areas. CONCLUSIONS: Despite MC prevalence increases in all priority countries since the onset of VMMC campaigns in 2008, MC prevalence remains below the 80% coverage target in most subnational areas and is highly variable. These mapped results provide an actionable tool for understanding local needs and informing VMMC interventions for maximum impact in the continued effort towards ending the HIV epidemic in sub-Saharan Africa.

Strategies for increasing impact, engagement, and accessibility in HIV prevention programs: suggestions from women in urban high HIV burden counties in the Eastern United States (HPTN 064).

BACKGROUND: Merely having the tools to end HIV is insufficient. Effectively ending the epidemic necessitates addressing barriers that impede engagement in biomedical and behavioral prevention and wide scale implementation and utilization of existing interventions. This qualitative study identifies suggestions for increasing access to, engagement in, and impact of HIV prevention among women living in cities in high HIV burden counties in the eastern US. METHODS: Data analyzed for the current study were collected via a qualitative sub-study within the HIV Prevention Trials Network Study 064 (HPTN 064), a multisite observational cohort study designed to estimate HIV incidence among women residing in communities with elevated HIV prevalence who also reported personal or partner characteristics associated with increased risk of HIV acquisition. Focus group and interview participants in the qualitative sub-study (N = 288) were from four cities in the eastern US. RESULTS: Thematic analyses revealed four themes describing women's most frequently stated ideas for improving prevention efforts: 1) Promote Multilevel Empowerment, 2) Create Engaging Program Content, 3) Build "Market Demand", and 4) Ensure Accessibility. We conducted additional analyses to identify contradictory patterns in the data, which revealed an additional three themes: 1) Address Structural Risk Factors, 2) Increase Engagement via Pleasure Promotion, 3) Expand Awareness of and Access to Prevention Resources. CONCLUSIONS: Findings may be useful for enhancing women's engagement in and uptake of behavioral and biomedical HIV prevention resources, improving policy, and addressing multilevel risk factors. TRIAL REGISTRATION: Clinicaltrials.gov: NCT00995176 , prospectively registered.

Threefold Increases in Population HIV Viral Load Suppression Among Men and Young Adults - Bukoba Municipal Council, Tanzania, 2014-2017.

Reducing HIV-related morbidity and mortality, and effectively eliminating HIV transmission risk, depends on use of antiretroviral therapy (ART) to achieve and maintain viral load suppression (VLS)* (1,2). By 2020, sub-Saharan African countries are working to achieve VLS among 90% of persons using ART and 73% of all persons living with HIV infection (1). In Tanzania, a country with 1.4 million persons with HIV infection, 49.6% of HIV-positive persons aged 15-49 years had achieved VLS in 2017, including only 21.5% of men and 44.6% of women aged 25-29 years (3). To identify interventions that might increase VLS in Tanzania, and reduce VLS-associated sex and age-group disparities, the Bukoba Combination Prevention Evaluation (BCPE) scaled up new HIV testing, linkage to care, and retention on ART interventions throughout Bukoba Municipal Council (Bukoba), Tanzania, during October 2014-March 2017 (4,5). Located on the western shore of Lake Victoria, Bukoba is a mixed urban and rural municipality of 150,000 persons and capital of Kagera Region. Of the 31 regions of Tanzania, Kagera has the fourth highest prevalence of HIV infection (6.8%) among residents aged 15-49 years (3). CDC analyzed data from BCPE preintervention and postintervention surveys and found that VLS prevalence among HIV-positive Bukoba residents aged 18-49 years increased approximately twofold overall (from 28.6% to 64.8%) and among women (33.3% to 67.8%) and approximately threefold among men (20.5% to 59.1%) and young adults aged 18-29 years (15.6% to 56.7%). During 2017, BCPE facility-based testing and linkage interventions were approved as new service delivery models by the Tanzania Ministry of Health, Community Development, Gender, Elderly and Children (4,5). After a successful rollout to 208 facilities in 11 regions in 2018, BCPE interventions are being scaled up in all regions of Tanzania in 2019 with support from the United States President's Emergency Plan for AIDS Relief (PEPFAR).†.

Sexual Risk and Intravaginal Practice Behavior Changes During Pregnancy.

Data suggest that pregnant women in some settings have high prevalence of HIV and other sexually transmitted infections (STI). We examined changes in sexual risk behaviors and intravaginal practices during pregnancy that may contribute to HIV and STI incidence using data from the Methods for Improved Reproductive Health in Africa study conducted in South Africa and Zimbabwe 2003-2006. We used a crossover design and modified Poisson regression to compare behaviors among HIV negative women 18-45 years during pregnant and non-pregnant periods. Among the 4802 women <45 years at enrollment, 483 (10.1 %) had a pregnancy and were included in the analysis. Compared to non-pregnant periods, pregnancy was associated with fewer than 3 sex acts per week (adjusted risk ratio [ARR] 0.89; 95 % CI 0.79-0.99) but more sex acts without condoms (ARR 1.32; 95 % CI 1.15-1.51). Pregnancy was also associated with decreased reporting of other sexual risk behaviors including any anal sex, multiple sexual partners, and/or sex in exchange for drugs or money. Women also reported less intravaginal wiping during pregnancy (ARR 0.84; 95 % CI 0.76-0.93). We found pregnancy decreased sexual activity and some high-risk sexual behaviors but increased the risk of sex without a condom.

Violence Against Women in Selected Areas of the United States.

OBJECTIVES: We determined the prevalence of recent emotional, physical, and sexual violence against women and their associations with HIV-related risk factors in women living in the United States. METHODS: We performed an assessment of women ages 18 to 44 years with a history of unprotected sex and 1 or more personal or partner HIV risk factors in the past 6 months from 2009 to 2010. We used multivariable logistic regression to examine the association of experiencing violence. RESULTS: Among 2099 women, the prevalence of emotional abuse, physical violence, and sexual violence in the previous 6 months was 31%, 19%, and 7%, respectively. Nonmarried status, food insecurity, childhood abuse, depression symptomology, and posttraumatic stress disorder were significantly associated with multiple types of violence. All types of violence were associated with at least 3 different partner or personal HIV risk behaviors, including unprotected anal sex, previous sexually transmitted infection diagnosis, sex work, or partner substance abuse. CONCLUSIONS: Our data suggested that personal and partner HIV risk behaviors, mental illness, and specific forms of violence frequently co-occurred in the lives of impoverished women. We shed light on factors purported to contribute to a syndemic in this population. HIV prevention programs in similar populations should address these co-occurring issues in a comprehensive manner.

Poor performance of the determine HIV-1/2 Ag/Ab combo fourth-generation rapid test for detection of acute infections in a National Household Survey in Swaziland.

Fourth-generation HIV rapid tests (RTs) claim to detect both p24 antigen (Ag) and HIV antibodies (Ab) for early identification of acute infections, important for targeting prevention and reducing HIV transmission. In a nationally representative household survey in Swaziland, 18,172 adults, age 18 to 49 years, received home-based HIV rapid testing in 2010 and 2011. Of the 18,172 individuals, 5,822 (32.0%) were Ab positive (Ab(+)) by the Determine HIV-1/2 Ab/Ab combo test, and 5,789 (99.4%) of those were confirmed to be reactive in the Uni-Gold test. Determine combo identified 12 individuals as having acute infections (Ag(+)/Ab negative [Ab(-)]); however, none had detectable HIV-1 RNA and 8 of 12 remained HIV negative at their 6-week follow-up visit (4 were lost to follow-up). All RT-nonreactive samples were pooled and tested by nucleic acid amplification testing (NAAT) to identify acute infections. NAAT identified 13 (0.1%) of the 12,338 HIV antibody-negative specimens as HIV RNA positive, with RNA levels ranging from 300 to >10,000,000 copies/ml. However, none of them were Ag(+) by Determine combo. Follow-up testing of 12 of the 13 NAAT-positive individuals at 6 months demonstrated 12 seroconversions (1 individual was lost to follow-up). Therefore, the Determine combo test had a sensitivity of 0% (95% confidence interval, 0 to 28) and positive predictive value of 0% for the detection of acute infections. The ability of the 4th-generation Determine combo to detect antigen was very poor in Swaziland. Thus, the Determine combo test does not add any value to the current testing algorithm; rather, it adds additional costs and complexity to HIV diagnosis. The detection of acute HIV infections may need to rely on other testing strategies.

HIV diversity as a biomarker for HIV incidence estimation: including a high-resolution melting diversity assay in a multiassay algorithm.

Multiassay algorithms (MAAs) can be used to estimate cross-sectional HIV incidence. We previously identified a robust MAA that includes the BED capture enzyme immunoassay (BED-CEIA), the Bio-Rad Avidity assay, viral load, and CD4 cell count. In this report, we evaluated MAAs that include a high-resolution melting (HRM) diversity assay that does not require sequencing. HRM scores were determined for eight regions of the HIV genome (2 in gag, 1 in pol, and 5 in env). The MAAs that were evaluated included the BED-CEIA, the Bio-Rad Avidity assay, viral load, and the HRM diversity assay, using HRM scores from different regions and a range of region-specific HRM diversity assay cutoffs. The performance characteristics based on the proportion of samples that were classified as MAA positive by duration of infection were determined for each MAA, including the mean window period. The cross-sectional incidence estimates obtained using optimized MAAs were compared to longitudinal incidence estimates for three cohorts in the United States. The performance of the HRM-based MAA was nearly identical to that of the MAA that included CD4 cell count. The HRM-based MAA had a mean window period of 154 days and provided cross-sectional incidence estimates that were similar to those based on cohort follow-up. HIV diversity is a useful biomarker for estimating HIV incidence. MAAs that include the HRM diversity assay can provide accurate HIV incidence estimates using stored blood plasma or serum samples without a requirement for CD4 cell count data.

HIV acquisition among women from selected areas of the United States: a cohort study.

BACKGROUND: Women account for 23% of newly diagnosed HIV infections in the United States, but there are few recent, well-characterized cohorts of U.S. women in whom behavior characteristics and HIV acquisition have been well-described. OBJECTIVE: To evaluate HIV incidence and describe behaviors among U.S. women residing in areas of high HIV prevalence. DESIGN: Multisite, longitudinal cohort of women who had HIV rapid testing and audio computer-assisted self-interviews at baseline and every 6 months for up to 12 months. (ClinicalTrials.gov: NCT00995176) SETTING: 10 urban and periurban communities with high HIV prevalence and poverty rates, located in the northeastern and southeastern United States. PATIENTS: Venue-based sampling was used to recruit women aged 18 to 44 years who recently had unprotected sex and had 1 or more additional personal or partner risk factors and no self-reported previous HIV diagnosis. MEASUREMENTS: HIV prevalence and incidence, frequency of HIV risk behaviors, and health status perceptions. RESULTS: Among 2099 high-risk women (85.9% black and 11.7% of Hispanic ethnicity), 32 (1.5%) were diagnosed with HIV infection at enrollment. Annual HIV incidence was 0.32% (95% CI, 0.14% to 0.74%). Older age, substance use, and knowing a partner had HIV were associated with HIV prevalence. Ten women died during the study (0.61% per year). LIMITATIONS: Longitudinal assessment of risk behaviors was limited to a maximum of 12 months. There were few incident HIV infections, precluding identification of characteristics predictive of HIV acquisition. CONCLUSION: This study enrolled a cohort of women with HIV incidence substantially higher than the Centers for Disease Control and Prevention national estimate in the general population of U.S. black women. Concerted efforts to improve preventive health care strategies for HIV and overall health status are needed for similar populations. PRIMARY FUNDING SOURCE: National Institutes of Health.

Use of a multifaceted approach to analyze HIV incidence in a cohort study of women in the United States: HIV Prevention Trials Network 064 Study.

BACKGROUND: Reliable methods for estimating the incidence of human immunodeficiency virus (HIV) infection are needed to monitor the epidemic, identify at-risk populations, and evaluate HIV prevention strategies. We used a multifaceted approach to estimate HIV incidence in the HIV Prevention Trials Network (HPTN) 064 study. METHODS: The HPTN 064 study enrolled 2067 HIV-seronegative women and 32 HIV-seropositive women with no prior HIV infection diagnosis. Women were followed for up to 12 months. HIV incidence estimates were based on (1) detection of acute HIV infection, (2) documentation of HIV seroconversion, and (3) detection of recent HIV infection, using a multiassay algorithm (MAA). RESULTS: Two women had acute HIV infection at enrollment, 4 seroconverted, and 2 were identified as recently infected at enrollment using the MAA. The annual HIV incidence estimate based on acute infection at enrollment (2.52% [95% confidence interval {CI}, .17%-9.33%], using a 14-day window period) was higher than the estimate based on seroconversion (0.24% [95% CI, .07%-.62%]; P = .027). Incidence estimates obtained using the MAA at enrollment and at the end of study were 0.25% (95% CI, .03%-.93%) and 0.13% (95% CI, .006%-.76%), respectively. CONCLUSIONS: We detected a high frequency of acute infection at enrollment. Cross-sectional HIV incidence estimates obtained using the MAA were similar to the longitudinal estimate based on HIV seroconversion. CLINICAL TRIALS REGISTRATION: NCT00995176.