Population Size Estimate of Men Who Have Sex with Men in Essex, New Jersey, To Inform Policy and Programming

BackgroundPopulation size estimates for key populations at risk for and living with HIV infection are key to understanding the need for and impact of HIV prevention and care. In this brief report we demonstrate approaches to estimating population size and unmet need for prevention and care among gay, bisexual, and other men who have sex with men (MSM) in Essex County, New Jersey.MethodsWe employed literature/census denominator and component methods of size estimation. We applied additional data points available electronically or in the published literature to estimate the number of undiagnosed MSM, the number of HIV negative men MSM in need of prevention programming.ResultsWe estimate a total of 11,362 MSM living in Essex County, New Jersey, of which 2,550 are HIV infected and of those 408 are not diagnosed. We estimate 8,812 HIV negative MSM in need of HIV prevention programs.ConclusionsThese estimates will allow future resources to be deployed in a more targeted and strategic manner, thereby bringing Essex County and New Jersey closer to achieving the 90-90-90 goals.

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Population Size Estimation of Gay and Bisexual Men and Other Men Who Have Sex With Men Using Social Media-Based Platforms (Preprint)

10.2196/preprints.9321 ◽

2017 ◽

Author(s):

Stefan Baral ◽

Rachael M Turner ◽

Carrie E Lyons ◽

Sean Howell ◽

Brian Honermann ◽

...

Keyword(s):

Social Media ◽

Hiv Prevention ◽

Population Size ◽

The United States ◽

Size Estimation ◽

Same Sex ◽

Care Needs ◽

Population Size Estimates ◽

Sex With Men ◽

Size Estimates

BACKGROUND Gay, bisexual, and other cisgender men who have sex with men (GBMSM) are disproportionately affected by the HIV pandemic. Traditionally, GBMSM have been deemed less relevant in HIV epidemics in low- and middle-income settings where HIV epidemics are more generalized. This is due (in part) to how important population size estimates regarding the number of individuals who identify as GBMSM are to informing the development and monitoring of HIV prevention, treatment, and care programs and coverage. However, pervasive stigma and criminalization of same-sex practices and relationships provide a challenging environment for population enumeration, and these factors have been associated with implausibly low or absent size estimates of GBMSM, thereby limiting knowledge about the dynamics of HIV transmission and the implementation of programs addressing GBMSM. OBJECTIVE This study leverages estimates of the number of members of a social app geared towards gay men (Hornet) and members of Facebook using self-reported relationship interests in men, men and women, and those with at least one reported same-sex interest. Results were categorized by country of residence to validate official size estimates of GBMSM in 13 countries across five continents. METHODS Data were collected through the Hornet Gay Social Network and by using an a priori determined framework to estimate the numbers of Facebook members with interests associated with GBMSM in South Africa, Ghana, Nigeria, Senegal, Côte d'Ivoire, Mauritania, The Gambia, Lebanon, Thailand, Malaysia, Brazil, Ukraine, and the United States. These estimates were compared with the most recent Joint United Nations Programme on HIV/AIDS (UNAIDS) and national estimates across 143 countries. RESULTS The estimates that leveraged social media apps for the number of GBMSM across countries are consistently far higher than official UNAIDS estimates. Using Facebook, it is also feasible to assess the numbers of GBMSM aged 13-17 years, which demonstrate similar proportions to those of older men. There is greater consistency in Facebook estimates of GBMSM compared to UNAIDS-reported estimates across countries. CONCLUSIONS The ability to use social media for epidemiologic and HIV prevention, treatment, and care needs continues to improve. Here, a method leveraging different categories of same-sex interests on Facebook, combined with a specific gay-oriented app (Hornet), demonstrated significantly higher estimates than those officially reported. While there are biases in this approach, these data reinforce the need for multiple methods to be used to count the number of GBMSM (especially in more stigmatizing settings) to better inform mathematical models and the scale of HIV program coverage. Moreover, these estimates can inform programs for those aged 13-17 years; a group for which HIV incidence is the highest and HIV prevention program coverage, including the availability of pre-exposure prophylaxis (PrEP), is lowest. Taken together, these results highlight the potential for social media to provide comparable estimates of the number of GBMSM across a large range of countries, including some with no reported estimates.

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shinyrecap: A Shiny Application for Population Size Estimation from Capture-Recapture Data (Preprint)

10.2196/preprints.32645 ◽

2021 ◽

Author(s):

Anne F. McIntyre ◽

Ian E. Fellows ◽

Steve Gutreuter ◽

Wolfgang Hladik

Keyword(s):

Population Size ◽

Sex Workers ◽

Female Sex Workers ◽

Population Size Estimation ◽

Sub Saharan Africa ◽

Size Estimation ◽

Female Sex ◽

Populations At Risk ◽

Population Size Estimates ◽

Capture Recapture

BACKGROUND Capture-recapture is often used to estimate the size of populations at risk for HIV, including female sex workers, men who have sex with men, and people who inject drugs. These population size estimates are critical in determining resource allocation for HIV services geared toward these communities. OBJECTIVE Compared to the commonly used two-source capture-recapture, capture-recapture relying on three (or more) samples can provide more robust PSE but involve far more complex statistical analysis. shinyrecap is designed to provide a user-friendly interface for the field epidemiologist. METHODS shinyrecap is built on the Shiny web application framework for R. This allows it to seamlessly integrate with the sophisticated CRC statistical packages. Additionally, the application may be accessed online or run locally on the user’s machine. RESULTS The application enables users to engage in sample size calculation based on a simulation framework. It assists in the proper formatting of collected data by providing a tool to convert commonly used formats to that used by analysis software. A wide variety of methodologies are supported by the analysis tool, including log-linear, Bayesian model averaging, and Bayesian latent class models. For each methodology, diagnostics and model checking interfaces are provided. CONCLUSIONS Through a use case, we demonstrate the broad utility of this powerful tool with three-source capture-recapture data to produce population size estimation for female sex workers in a subnational unit of a country in sub-Saharan Africa.

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Estimating the population size of people who inject drugs in Ho Chi Minh City, Vietnam: A two-survey capture-recapture exercise (Preprint)

10.2196/preprints.16459 ◽

2019 ◽

Author(s):

Abu Abdul-Quader

Keyword(s):

Population Size ◽

Illicit Drugs ◽

People Who Inject Drugs ◽

Care Service ◽

Ho Chi Minh City ◽

Size Estimation ◽

Population Size Estimates ◽

Capture Recapture ◽

The City ◽

Size Estimates

BACKGROUND Population size estimation of people who inject drugs (PWID) in Ho Chi Minh City (HCMC), Vietnam relied on the UNAIDS Estimation and Projection Package and reports from the city police department. The two estimates vary widely. OBJECTIVE To estimate the population size of people who inject drugs in Ho Chi Minh City, Vietnam METHODS Using Respondent-driven sampling (RDS), we implemented two-source capture-recapture method to estimate the population size of PWID in HCMC in 2017 in 7 out of 24 districts. The study included men or women aged at least 18 years who reported injecting illicit drugs in the last 90 days and who had lived in the city the past six months. We calculated two sets of size estimates, the first assumed that all participants in each survey round resided in the district where the survey was conducted, the second, used the district of residence as reported by the participant. District estimates were summed to obtain an aggregate estimate for the seven districts. To calculate the city total, we weighted the population size estimates for each district by the inverse of the stratum specific sampling probabilities. RESULTS The first estimate resulted in a population size of 19,155 (95% CI: 17,006–25,039). The second one generated a smaller population size estimate of 12,867 (95% CI: 11,312–17,393). CONCLUSIONS The two-survey capture-recapture exercise provided two disparate estimates of PWID in HCMC. For planning HIV prevention and care service needs among PWID in HCMC, both estimates may need to be taken into consideration together with size estimates from other sources.

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Southern African guidelines for the safe use of pre-exposure prophylaxis in men who have sex with men who are at risk for HIV infection

Southern African Journal of HIV Medicine ◽

10.4102/sajhivmed.v13i2.136 ◽

2012 ◽

Vol 13 (2) ◽

Cited By ~ 2

Author(s):

Southern African HIV Clinicians Society Consensus Committee

Keyword(s):

At Risk ◽

Renal Function ◽

Hiv Prevention ◽

Hepatitis B ◽

Hiv Infection ◽

Creatinine Clearance ◽

Fixed Dose ◽

Sex With Men ◽

Exposure Prophylaxis ◽

Hiv Negative

Background. The use of oral antiretrovirals to prevent HIV infection among HIV-negative men who have sex with men (MSM) has been shown to be safe and efficacious. A large, randomised, placebo-controlled trial showed a 44% reduction in the incidence of HIV infection among MSM receiving a daily oral fixed-dose combination of tenofovir disoproxil fumarate and emtricitabine (Truvada) in combination with an HIV prevention package. Improved protection was seen with higher levels of adherence. Aim. The purpose of this guideline is to: (i) explain what pre-exposure prophylaxis (PrEP) is; (ii) outline current indications for its use; (iii) outline steps for appropriate client selection; and (iv) provide guidance for monitoring and maintaining clients on PrEP. Method. PrEP is indicated for HIV-negative MSM who are assessed to be at high risk for HIV acquisition and who are willing and motivated to use PrEP as part of a package of HIV prevention services (including condoms, lubrication, sexually transmitted infection (STI) management and risk reduction counselling). Recommendations. HIV testing, estimation of creatinine clearance and STI and hepatitis B screening are recommended as baseline investigations. Daily oral Truvada, along with adherence support, can then be prescribed for eligible MSM. PrEP should not be given to MSM with abnormal renal function, nor to clients who are unmotivated to use PrEP as part of an HIV prevention package; nor should it be commenced during an acute viral illness. Three-monthly follow-up visits to assess tolerance, renal function, adherence and ongoing eligibility is recommended. Six-monthly STI screens and annual creatinine levels to estimate creatinine clearance are recommended. Hepatitis B vaccination should be provided to susceptible clients. Gastro-intestinal symptoms and weight loss are common side-effects, mostly experienced for the first 4 - 8 weeks after initiating PrEP. There is a risk of the development of antiretroviral resistance among those with undiagnosed acute HIV infection during PrEP initiation and among those with sub-optimal adherence who become HIV infected while on PrEP. Risk compensation (increasing sexual behaviours that can result in exposure to HIV) while on PrEP may become a concern, and clinicians should continue to support MSM clients to continue to use condoms, condom-compatible lubrication and practice safer sex. Research is ongoing to assess optimum dosing regimens, potential long-term effects and alternative PrEP medications. Recommendations for the use of PrEP among other at-risk individuals, and the components of these recommendations, will be informed by future evidence. S Afr J HIV Med 2012;13(2):40-55.

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Estimating the Population Size of Female Sex Workers in Namibia Using a Respondent-Driven Sampling Adjustment to the Reverse Tracking Method: A Novel Approach (Preprint)

10.2196/preprints.11737 ◽

2018 ◽

Author(s):

Paul Douglas Wesson ◽

Rajatashuvra Adhikary ◽

Anna Jonas ◽

Krysta Gerndt ◽

Ali Mirzazadeh ◽

...

Keyword(s):

Population Size ◽

Sex Workers ◽

Female Sex Workers ◽

Respondent Driven Sampling ◽

Double Counting ◽

Size Estimation ◽

Tracking Method ◽

Female Sex ◽

Population Size Estimates ◽

Size Estimates

BACKGROUND Key populations, including female sex workers (FSWs), are at a disproportionately high risk for HIV infection. Estimates of the size of these populations serve as denominator data to inform HIV prevention and treatment programming and are necessary for the equitable allocation of limited public health resources. OBJECTIVE This study aimed to present the respondent-driven sampling (RDS) adjusted reverse tracking method (RTM; RadR), a novel population size estimation approach that combines venue mapping data with RDS data to estimate the population size, adjusted for double counting and nonattendance biases. METHODS We used data from a 2014 RDS survey of FSWs in Windhoek and Katima Mulilo, Namibia, to demonstrate the RadR method. Information from venue mapping and enumeration from the survey formative assessment phase were combined with survey-based venue-inquiry questions to estimate population size, adjusting for double counting, and FSWs who do not attend venues. RadR estimates were compared with the official population size estimates, published by the Namibian Ministry of Health and Social Services (MoHSS), and with the unadjusted RTM. RESULTS Using the RadR method, we estimated 1552 (95% simulation interval, SI, 1101-2387) FSWs in Windhoek and 453 (95% SI: 336-656) FSWs in Katima Mulilo. These estimates were slightly more conservative than the MoHSS estimates—Windhoek: 3000 (1800-3400); Katima Mulilo: 800 (380-2000)—though not statistically different. We also found 75 additional venues in Windhoek and 59 additional venues in Katima Mulilo identified by RDS participants’ responses that were not detected during the initial mapping exercise. CONCLUSIONS The RadR estimates were comparable with official estimates from the MoHSS. The RadR method is easily integrated into RDS studies, producing plausible population size estimates, and can also validate and update key population maps for outreach and venue-based sampling.

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A Web-Based Study of HIV Prevention in the Era of Pre-Exposure Prophylaxis Among Vulnerable HIV-Negative Gay and Bisexual Men, Transmen, and Transwomen Who Have Sex With Men: Protocol for an Observational Cohort Study (Preprint)

10.2196/preprints.13715 ◽

2019 ◽

Author(s):

Denis Nash ◽

Matthew Stief ◽

Caitlin MacCrate ◽

Chloe Mirzayi ◽

Viraj V Patel ◽

...

Keyword(s):

High Risk ◽

Hiv Prevention ◽

Hiv Testing ◽

The United States ◽

Racially Diverse ◽

Web Based ◽

Sex With Men ◽

Hiv Acquisition ◽

Exposure Prophylaxis ◽

Hiv Negative

BACKGROUND Gay, bisexual, and other men who have sex with men continue to bear a large burden of the HIV epidemic in the United States and are among the only populations with increasing incidence in recent years. OBJECTIVE The Together 5000 (T5K) Study aimed to enroll a US-based, racially diverse sample of HIV-negative men, transmen, and transwomen who are not on pre-exposure prophylaxis (PrEP) into an observational cohort to inform the design, implementation, scale-up, and evaluation of HIV prevention programs. METHODS We used internet-based strategies to enroll a large, racially diverse national sample of HIV-negative men, transmen, and transwomen aged 16 to 49 years at high risk of HIV acquisition via sexual networking apps. Study participants are contacted every 6 months (in between annual surveys) for a brief survey on HIV testing, HIV diagnosis, and PrEP use (ie, attempts to access, PrEP initiation, and PrEP discontinuation). Participants complete annual self-administered at-home HIV testing and Web-based surveys. Using baseline serologic data and self-reported HIV testing history, we reconstructed a cohort of persons who were HIV negative at 12 months before baseline to estimate HIV incidence leading up to cohort enrollment. RESULTS The study sample included 8777 participants from all 50 US states, Puerto Rico, and Guam; 50.91% (4468/8777) were persons of color and 25.30% (2221/8777) were young individuals aged 16 to 24 years. Per eligibility criteria, all T5K participants reported having sex with >2 male partners in the 90 days before enrollment, self-reported not having been diagnosed with HIV, and were not actively taking PrEP. In addition, 79.39% (6968/8777) reported >2 insertive condomless anal sex (CAS) acts, 61.02% (5356/8777) reported >1 receptive CAS acts in the past 90 days. Furthermore, most (7525/8777, 85.74%) reported never having taken PrEP. In total, 70.25% (6166/8777) were sent a self-administered at-home HIV test kit and 82.29% (5074/6166) of those sent a kit returned a sample for testing. The HIV incidence rate during the 12-month period leading up to enrollment was estimated to be 2.41 (95% CI 2.02-2.90) per 100 person-years. CONCLUSIONS A large, national, and racially diverse fully Web-based cohort of HIV-negative men, transmen, and transwomen at high risk for HIV seroconversion has successfully been recruited into longitudinal follow-up. This cohort is at high risk for HIV acquisition and can provide important insights related to the real-world uptake, impact, and equity of HIV prevention interventions in the United States. Participants can be invited to participate in trials aimed at testing strategies to improve the uptake of and engagement in these interventions. INTERNATIONAL REGISTERED REPORT RR1-10.2196/13715

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863. Increasing PrEP Uptake: A Diffusion-Based Network Intervention for HIV Prevention Among Young Black Men Who Have Sex With Men

Open Forum Infectious Diseases ◽

10.1093/ofid/ofy209.048 ◽

2018 ◽

Vol 5 (suppl_1) ◽

pp. S21-S22

Author(s):

Matthew Ferreira ◽

Lindsay Young ◽

John Schneider

Keyword(s):

Hiv Prevention ◽

Hiv Infection ◽

Black Men ◽

Controlled Trial ◽

Biomedical Intervention ◽

Network Intervention ◽

Sex With Men ◽

Hiv Negative ◽

Peer Leader

Abstract Background Advances in biomedical prevention strategies provide new opportunities for reducing HIV incidence among young black men who have sex with men (YBMSM). Pre-exposure prophylaxis (PrEP) is for HIV-negative individuals and has been shown to be up to 99% effective in preventing HIV infection when taken as prescribed by CDC clinical practice guidelines. Several studies, however, have documented low rates of PrEP uptake among YBMSM. Methods PrEP Chicago is a randomized controlled trial peer leader intervention designed to promote uptake of PrEP for HIV prevention among YBMSM. Participants (n = 423) were recruited using respondent-driven sampling (RDS) and randomized to either an intervention (n = 209) or control (n = 214) condition. Eligibility criteria included: aged 18–35, identifies as a person of color, assigned male sex at birth, had sex with a man in the past 12 months, had an active Facebook profile, and resided in Chicago. The intervention includes a half-day, small group PrEP, and peer leader training workshop followed by monthly check-in booster calls. Approximately 12 months after their initial baseline visit, participants return to complete follow-up data collection and switch conditions, giving year 1 control participants the opportunity to learn about PrEP. Results The number of HIV-negative intervention participants on PrEP at baseline vs. 12-month follow-up (PrEP Chicago Study, Chicago, 2016–2018). A total of 341 participants (80.6%) returned at 12 months. Of 209 intervention participants at baseline, 176 (84.2%) completed a follow-up survey at 12 months. At baseline, 13 (13.3%) of 98 HIV-negative intervention participants indicated that they were currently taking PrEP. At 12 months, this number grew to 25 (32.5%) of 77 HIV-negative intervention participants, indicating that they were currently taking PrEP. A total of 21 participants reported initiating PrEP during their time in the intervention. Conclusion PrEP is a valuable biomedical intervention for preventing HIV infection in those at risk. PrEP Chicago, a network intervention designed to promote uptake of PrEP among YBMSM, shows promising results for PrEP adoption among this community. Disclosures All authors: No reported disclosures.

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Preliminary evidence of HIV seroconversion among HIV-negative men who have sex with men taking non-prescribed antiretroviral medication for HIV prevention in Miami, Florida, USA

Sexual Health ◽

10.1071/sh16108 ◽

2017 ◽

Vol 14 (2) ◽

pp. 193 ◽

Cited By ~ 7

Author(s):

Mance E. Buttram ◽

Steven P. Kurtz

Keyword(s):

Hiv Prevention ◽

Hiv Transmission ◽

Qualitative Interviews ◽

Transmission Risk ◽

Accurate Information ◽

Limited Information ◽

Antiretroviral Medication ◽

Hiv Seroconversion ◽

Sex With Men ◽

Hiv Negative

Background Limited information suggests that men who have sex with men (MSM) are informally obtaining antiretroviral medication (ARVs) and using them for HIV pre-exposure prophylaxis (PrEP). Methods: Data are drawn from an on-going study examining the use of non-prescribed ARVs for PrEP. To date, 24 qualitative interviews have been conducted with HIV-negative, substance-using MSM living in Miami, Florida, USA. Data are presented from two participants who reported HIV seroconversion while using non-prescribed ARVs for PrEP. Results: Preliminary data indicate that some young MSM: (i) lack awareness of and accurate information about the efficacious use of PrEP; (ii) obtain non-prescribed ARVs from HIV-positive sex partners and use these medications for PrEP in a way that does not provide adequate protection against HIV infection or cohere with established guidelines; and (iii) engage in multiple HIV transmission risk behaviours, including condomless anal sex and injection drug use. Conclusions: The informal, non-prescribed and non-medically supervised use of ARVs for HIV prevention has the potential to undermine the protective benefits of PrEP and leave men unprotected against HIV transmission and at risk for ARV resistance.

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Inferring pandemic growth rates from sequence data

Journal of The Royal Society Interface ◽

10.1098/rsif.2011.0850 ◽

2012 ◽

Vol 9 (73) ◽

pp. 1797-1808 ◽

Cited By ~ 27

Author(s):

Eric de Silva ◽

Neil M. Ferguson ◽

Christophe Fraser

Keyword(s):

Population Size ◽

Effective Population Size ◽

Sequence Data ◽

Simulated Data ◽

Parametric Methods ◽

Sampling Strategies ◽

Size Estimation ◽

Effective Population ◽

Population Size Estimates ◽

Non Parametric

Using sequence data to infer population dynamics is playing an increasing role in the analysis of outbreaks. The most common methods in use, based on coalescent inference, have been widely used but not extensively tested against simulated epidemics. Here, we use simulated data to test the ability of both parametric and non-parametric methods for inference of effective population size (coded in the popular BEAST package) to reconstruct epidemic dynamics. We consider a range of simulations centred on scenarios considered plausible for pandemic influenza, but our conclusions are generic for any exponentially growing epidemic. We highlight systematic biases in non-parametric effective population size estimation. The most prominent such bias leads to the false inference of slowing of epidemic spread in the recent past even when the real epidemic is growing exponentially. We suggest some sampling strategies that could reduce (but not eliminate) some of the biases. Parametric methods can correct for these biases if the infected population size is large. We also explore how some poor sampling strategies (e.g. that over-represent epidemiologically linked clusters of cases) could dramatically exacerbate bias in an uncontrolled manner. Finally, we present a simple diagnostic indicator, based on coalescent density and which can easily be applied to reconstructed phylogenies, that identifies time-periods for which effective population size estimates are less likely to be biased. We illustrate this with an application to the 2009 H1N1 pandemic.

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Population Size Estimation Methods: Searching for the Holy Grail (Preprint)

10.2196/preprints.25076 ◽

2020 ◽

Author(s):

Joyce J Neal ◽

Dimitri Prybylski ◽

Travis Sanchez ◽

Wolfgang Hladik

Keyword(s):

Population Size ◽

Sex Workers ◽

Population Size Estimation ◽

Estimation Methods ◽

Size Estimation ◽

Empirical Methods ◽

Program Outcomes ◽

Gold Standard Method ◽

Response Planning ◽

Sex With Men

UNSTRUCTURED Accurate size estimates of key populations (eg, sex workers, people who inject drugs, transgender people, and men who have sex with men) can help to ensure adequate availability of services to prevent or treat HIV infection; inform HIV response planning, target setting, and resource allocation; and provide data for monitoring and evaluating program outcomes and impact. A gold standard method for population size estimation does not exist, but quality of estimates could be improved by using empirical methods, multiple data sources, and sound statistical concepts. To highlight such methods, a special collection of papers in JMIR Public Health and Surveillance has been released under the title “Key Population Size Estimations.” We provide a summary of these papers to highlight advances in the use of empirical methods and call attention to persistent gaps in information.

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