Gonorrhea, Chlamydia and HIV incidence among female sex workers in Cotonou, Benin: A longitudinal study

HIV incidence among women engaging in sex work in sub-Saharan Africa: a systematic review and meta-analysis

BACKGROUND

Women who engage in sex work in sub-Saharan Africa have a high risk of acquiring HIV infection. HIV incidence has declined among all women in sub-Saharan Africa, but trends among women who engage in sex work are poorly characterised. We synthesised data on HIV incidence among women who engage in sex work in sub-Saharan Africa and compared these with the total female population to understand relative incidence and trends over time.

METHODS

We searched MEDLINE, Embase, Global Health, and Google Scholar from Jan 1, 1990, to Feb 28, 2024, and grey literature for studies that reported empirical estimates of HIV incidence among women who engage in sex work in any sub-Saharan Africa country. We calculated incidence rate ratios (IRRs) compared with total female population incidence estimates matched for age, district, and year, did a meta-analysis of IRRs, and used a continuous mixed-effects model to estimate changes in IRR over time.

FINDINGS

From 32 studies done between 1985 and 2020, 2194 new HIV infections were observed among women who engage in sex work over 51 490 person-years. Median HIV incidence was 4·3 per 100 person years (IQR 2·8-7·0 per 100 person-years). Incidence among women who engage in sex work was eight times higher than matched total population women (IRR 7·8 [95% CI 5·1-11·8]), with larger relative difference in western and central Africa (19·9 [9·6-41·0]) than in eastern and southern Africa (4·9 [3·4-7·1]). There was no evidence that IRRs changed over time (IRR per 5 years: 0·9 [0·7-1·2]).

INTERPRETATION

Across sub-Saharan Africa, HIV incidence among women who engage in sex work remains disproportionately high compared with the total female population. However, constant relative incidence over time indicates HIV incidence among women who engage in sex work has declined at a similar rate. Location-specific data for women who engage in sex work incidence are sparse, but improved surveillance and standardisation of incidence measurement approaches could fill these gaps. Sustained and enhanced HIV prevention for women who engage in sex work is crucial to address continuing inequalities and ensure declines in new HIV infections.

FUNDING

Bill & Melinda Gates Foundation, UK Research and Innovation, National Institutes of Health.

TRANSLATION

For the French translation of the abstract see Supplementary Materials section.

HIV incidence among women engaging in sex work in sub-Saharan Africa: a systematic review and meta-analysis

Introduction

HIV incidence among women in sub-Saharan Africa (SSA) has declined steadily, but it is unknown whether new infections among women who engage in sex work (WESW) have declined at a similar rate. We synthesised estimates of HIV incidence among WESW in SSA and compared these to the wider female population to understand levels and trends in incidence over time.

Methods

We searched Medline, Embase, Global Health, Popline, Web of Science, and Google Scholar from January 1990 to October 2022, and grey literature for estimates of HIV incidence among WESW in SSA. We included studies reporting empirical estimates in any SSA country. We calculated incidence rate ratios (IRR) compared to age-district-year matched total female population incidence estimates. We conducted a meta-analysis of IRRs and used a continuous mixed-effects model to estimate changes in IRR over time.

Results

From 32 studies between 1985 and 2020, 2,194 new HIV infections were observed in WESW over 51,000 person-years (py). Median HIV incidence was 4.3/100py (IQR 2.8-7.0/100py), declining from a median of 5.96/100py between 1985 and 1995 to a median of 3.2/100py between 2010 and 2020. Incidence among WESW was nine times higher than in matched total population women (RR 8.6, 95%CI: 5.7-12.9), and greater in Western and Central Africa (RR 22.4, 95%CI: 11.3-44.3) than in Eastern and Southern Africa (RR 5.3, 95%CI: 3.7-7.6). Annual changes in log IRRs were minimal (-0.1% 95%CI: -6.9 to +6.8%).

Conclusions

Across SSA, HIV incidence among WESW remains disproportionately high compared to the total female population but showed similar rates of decline between 1990 and 2020. Improved surveillance and standardisation of approaches to obtain empirical estimates of sex worker incidence would enable a clearer understanding of whether we are on track to meet global targets for this population and better support data-driven HIV prevention programming.

Facilitators and Barriers for Chlamydia and Gonorrhea Testing in Female Sex Workers: A Scoping Review

We conducted a scoping review to examine the barriers and facilitators accessing Chlamydia trachomatis and Neisseria gonorrhoeae testing among female sex workers. A literature search was conducted in Embase, Medline, and Web of Science for studies published from the date of creation of database to 17 March 2023, without restrictions for publication date. We used thematic synthesis to identify common affecting factors across included studies and then linked them into categories of the socioecological framework. Among the 14 articles included, 3 utilized qualitative methods, 7 utilized quantitative surveys, 2 were mixed methods, and 2 were randomized controlled trials. Several important affecting factors stood out during this review, including stigma and discrimination, as well as social support at the societal level, and financial costs at the service level. This review suggested that interventions on addressing societal- and service-level determinants are needed, which includes reducing stigma and discrimination toward sex work and cost for facility testing, as well as increasing social support and community engagement.

Incidence of HIV infection and associated factors among female sex workers in Côte d’Ivoire, results of the ANRS 12361 PrEP-CI study using recent infection assays

Background

This study aimed to estimate, using an HIV Recent Infection Testing Algorithm (RITA), the HIV incidence and its associated factors among female sex workers (FSW) in Côte d’Ivoire.

Methods

A cross-sectional study was conducted in 2016–2017 in Abidjan and San Pedro’s region among FSW aged ≥ 18 years. In addition, a sociodemographic questionnaire, HIV screening was carried out by two rapid tests. In the event of a positive result, a dried blood spot sample was taken to determine, using a RITA adapted to the Ivorian context, if it was a recent HIV infection.

Results

A total of 1000 FSW were surveyed with a median age of 25 years (interquartile range: 21–29 years). 39 (3.9%) tested positive for HIV. The incidence of HIV was estimated to be 2.3 per 100 person-years, with higher incidence rates among those 24 years old or less (3.0% vs. 1.9%), non-Ivorian FSW (3.2% vs. 1.9%) and those with the lowest education level (4.6% in FSW who never went to school vs. 2.6%). The incidence seemed to be associated with the sex work practice conditions: higher incidence among FSW whose usual price was less than 3.50$ (4.3% vs.1.0%), FSW who had a larger number of clients on the last day of work (6.1% in those with 7 clients or more vs. 1.8%), FSW who reported not always using condoms with their clients (8.5% vs. 1.5%) and FSW who reported agreeing to sex without a condom in exchange for a large sum of money (10.1% vs. 1.2%).

Conclusion

This study confirms that FSW remain highly exposed to HIV infection. Exposure to HIV is also clearly associated with certain sex-work factors and the material conditions of sex work. Efforts in the fight against HIV infection must be intensified to reduce new infections among FSW.

High burden of self-reported sexually transmitted infections among female sex workers in Togo in 2021

Background

Sexually Transmitted Infections (STI) remain a public health challenge, especially for Female Sex Workers (FSW) who are particularly vulnerable. In sub-Saharan Africa where the overlapping epidemics of STI and HIV are concentrated among key populations, epidemiological data are needed in order to better understand STI trends in this population. The aim of this study was to assess the prevalence of self-reported STI symptoms and their risk factors among FSW in Togo in 2021.

Methods

A cross-sectional study was completed in June and July 2021 among FSW in two cities of Togo: in Lomé (capital city, south of Togo) and in Kara (north of Togo). A snowball sampling method was used and after consent, a standardized questionnaire was administered by trained research staff to collect information on STI. A multivariate logistic regression model was used to identify factors associated with self-reported STI.

Results

A total of 447 FSW, 300 in Lomé and 147 in Kara participated in this study. Median age was 30 [IQR: 24-38] and STI symptoms in the previous 12 months were reported by 191 FSW [42.7%, 95% CI: (38.1-47.5)], among whom 116 (60.7%) sought medical care. The most common reported symptoms were abnormal vaginal discharge (n = 78; 67.2%) and vaginal itching (n = 68; 58.6%). Current STI symptoms (at the time of the survey) were reported by 88 FSW (19.7%). In multivariable logistic regression, self-reported STI symptoms in the previous 12 months was negatively associated with living in the Lomé and older age and positively associated with having more than 15 clients in the previous week and being victim of violence.

Conclusions

Findings from this study reveal that the self-reported STI burden is relatively high among FSW Togo. Additional strategies are needed at the structural, medical, political and social levels to curb this trend and effectively aim at the elimination of STI epidemics by the year 2030.

Predictive Factors of HIV-1 Drug Resistance and Its Distribution among Female Sex Workers in the Democratic Republic of the Congo (DRC)

The predictive factors of HIV-1 drug resistance and its distribution are poorly documented in female sex workers (FSWs) in the Democratic Republic of the Congo (DRC). However, the identification of predictive factors can lead to the development of improved and effective antiretroviral therapy (ART). The objective of the current study was to determine the predictive factors of HIV-1 drug resistance and its distribution based on FSWs in the studied regions in the Democratic Republic of the Congo (DRC). HIV-positive FSWs who were diagnosed as part of the DRC Integrated Biological and Behavioral Surveillance Survey (IBBS) were included in this study. A total of 325 FSWs participated. The HIV-1 viral load (VL) was measured according to the Abbott m2000sp and m2000rt protocols. The homogeneity chi-square test was conducted to determine the homogeneity of HIV-1 drug resistance distribution. Using a significance level of 0.05, multivariate analyses were performed to identify factors associated with HIV-1 drug resistance to ART. HIV drug resistance mutation (HIVDRM) distribution was homogeneous in the three study regions (p = 0.554) but differed based on the HIV-1 VLs of the FSWs. FSWs with high HIV-1 VLs harbored more HIVDRMs (p = 0.028) of predominantly pure HIV-1 strains compared with those that had low HIV-1 VLs. Sexually transmitted infection (STI) history (aOR [95%CI] = 8.51 [1.62, 44.74]), high HIV-1 VLs (aOR [95%CI] = 5.39 [1.09, 26.74]), and HIV-1-syphilis coinfection (aOR [95%CI] = 9.71 [1.84, 51.27]) were associated with HIV drug resistance among FSWs in the DRC. A history of STIs (e.g., abnormal fluid) in the 12 months prior to the survey, a high HIV-1 VL, and HIV-1-syphilis coinfection were associated with HIV-1 drug resistance among FSWs in the DRC. Efforts should be made to systematically test for other infections which increase the HIV-1 VL, in the case of HIV-1 coinfection, in order to maintain ART effectiveness across the DRC.

Derivation of an HIV Risk Score for African Women Who Engage in Sex Work

No tool exists to stratify HIV risk in contemporary African female sex worker (FSW) populations. Data from a cohort of HIV-negative FSWs in Mombasa, Kenya from 2010 to 2017 were used to conduct a survival analysis assessing predictors of HIV infection. Stepwise regression was used to construct a multivariable model that formed the basis for the score. Seventeen HIV infections occurred over 1247 person-years of follow-up contributed by 670 women. Using depot medroxyprogesterone acetate (DMPA), having a curable sexually transmitted infection (STI), and being married contributed points to the score. HIV incidence was 0.85/100 person-years in a lower-risk group and 3.10/100 person-years in a higher-risk group. In a cohort with overall HIV incidence < 1.50/100 person-years, this risk score identified a subgroup of FSWs with HIV incidence > 3.00/100 person-years, which is the threshold used by the World Health Organization for initiating pre-exposure prophylaxis (PrEP). If validated in an external population, this tool could be useful for targeted PrEP promotion among higher-risk FSWs.

Assessing the Potential Impact of Disruptions Due to COVID-19 on HIV Among Key and Lower-Risk Populations in the Largest Cities of Cameroon and Benin

BACKGROUND

The COVID-19 pandemic indirectly impacts HIV epidemiology in Central/West Africa. We estimated the potential impact of COVID-19-related disruptions to HIV prevention/treatment services and sexual partnerships on HIV incidence and HIV-related deaths among key populations including female sex workers (FSW), their clients, men who have sex with men, and overall.

SETTING

Yaoundé (Cameroon) and Cotonou (Benin).

METHODS

We used mathematical models of HIV calibrated to city population-specific and risk population-specific demographic/behavioral/epidemic data. We estimated the relative change in 1-year HIV incidence and HIV-related deaths for various disruption scenarios of HIV prevention/treatment services and decreased casual/commercial partnerships, compared with a scenario without COVID-19.

RESULTS

A 50% reduction in condom use in all partnerships over 6 months would increase 1-year HIV incidence by 39%, 42%, 31%, and 23% among men who have sex with men, FSW, clients, and overall in Yaoundé, respectively, and 69%, 49%, and 23% among FSW, clients, and overall, respectively, in Cotonou. Combining a 6-month interruption of ART initiation and 50% reduction in HIV prevention/treatment use would increase HIV incidence by 50% and HIV-related deaths by 20%. This increase in HIV infections would be halved by a simultaneous 50% reduction in casual and commercial partnerships.

CONCLUSIONS

Reductions in condom use after COVID-19 would increase infections among key populations disproportionately, particularly FSW in Cotonou, who need uninterrupted condom provision. Disruptions in HIV prevention/treatment services have the biggest impacts on HIV infections and deaths overall, only partially mitigated by equal reductions in casual/commercial sexual partnerships. Maintaining ART provision must be prioritized to minimize short-term excess HIV-related deaths.

Condom use, symptoms of suggestive sexually transmitted infections, and health care seeking among female sex workers in Bangladesh

This article presents a mixed-method cross-sectional study reporting condom use, sexually transmitted infection (STI) symptoms, and care seeking of female sex workers (FSWs) in Dhaka, Bangladesh. A survey of 1228 FSWs, in-depth interviews (n = 24), and key informants' interviews (n = 26) were used for data collection. Among the 1228 FSWs included in this study, 50% of them were illiterate and 39.3% were married, and their mean age was 27.1 years. The consistent use of condoms was reported by 75.6% of the FSWs, 88.7% reported having STI symptoms in the last 6 months, while 91.8% visited one of the drop-in centers for services. FSWs without formal education had lower odds of using condoms consistently (AOR: 0.72; 95% CI: 0.55-0.95), and those working elsewhere than in the streets showed higher odds (AOR: 1.63; 95% CI: 1.23-2.15) to use condoms. Stigma to access health care services, poor knowledge about STI/HIV, and low perceived risk were mentioned as causes of having STI symptoms in the survey as well as in qualitative in-depth interviews. Self-reported condom use, STI symptoms, and care-seeking practices were found to be high among the FSWs. Inconsistent condom use and a high number of sex partners could be the reasons for high levels of STI symptoms. Innovative objectively verifiable approaches should be tested to collect condom use data.

Mathematical Model Impact Analysis of a Real-Life Pre-exposure Prophylaxis and Treatment-As-Prevention Study Among Female Sex Workers in Cotonou, Benin

BACKGROUND

Daily pre-exposure prophylaxis (PrEP) and treatment-as-prevention (TasP) reduce HIV acquisition and transmission risk, respectively. A demonstration study (2015-2017) assessed TasP and PrEP feasibility among female sex workers (FSW) in Cotonou, Benin.

SETTING

Cotonou, Benin.

METHODS

We developed a compartmental HIV transmission model featuring PrEP and antiretroviral therapy (ART) among the high-risk (FSW and clients) and low-risk populations, calibrated to historical epidemiological and demonstration study data, reflecting observed lower PrEP uptake, adherence and retention compared with TasP. We estimated the population-level impact of the 2-year study and several 20-year intervention scenarios, varying coverage and adherence independently and together. We report the percentage [median, 2.5th-97.5th percentile uncertainty interval (95% UI)] of HIV infections prevented comparing the intervention and counterfactual (2017 coverages: 0% PrEP and 49% ART) scenarios.

RESULTS

The 2-year study (2017 coverages: 9% PrEP and 83% ART) prevented an estimated 8% (95% UI 6-12) and 6% (3-10) infections among FSW over 2 and 20 years, respectively, compared with 7% (3-11) and 5% (2-9) overall. The PrEP and TasP arms prevented 0.4% (0.2-0.8) and 4.6% (2.2-8.7) infections overall over 20 years, respectively. Twenty-year PrEP and TasP scale-ups (2035 coverages: 47% PrEP and 88% ART) prevented 21% (17-26) and 17% (10-27) infections among FSW, respectively, and 5% (3-10) and 17% (10-27) overall. Compared with TasP scale-up alone, PrEP and TasP combined scale-up prevented 1.9× and 1.2× more infections among FSW and overall, respectively.

CONCLUSIONS

The demonstration study impact was modest, and mostly from TasP. Increasing PrEP adherence and coverage improves impact substantially among FSW, but little overall. We recommend TasP in prevention packages.

Sociodemographic factors and STIs associated with Chlamydia trachomatis and Neisseria gonorrhoeae infections in Zambian female sex workers and single mothers

Sexually transmitted infections (STIs) in women caused by Chlamydia trachomatis (CT) and/or Neisseria gonorrhoeae (NG) are epidemiologically distinct. In this study, associations with sociodemographic and clinical risk factors are explored separately for CT and NG. Multivariate logistic regression (MLR) models quantify associations between potential CT and/or NG risk factors within a cross-sectional study of high-risk women in two Zambian cities, Lusaka and Ndola. CT was associated with living in Lusaka, younger age, and literacy. Long-acting reversible contraception (LARC) was predictive of CT in Ndola, but protective in Lusaka. In Lusaka only, CT was associated with lower education and reported unprotected sex. NG was associated with younger age, lower education, concurrent Trichomonas vaginalis, bacterial vaginosis, and incident syphilis infection. Signs and symptoms were rare and not associated with either infection. CT was more prevalent, nearly 11%, compared to NG, 6.8%. The higher prevalence of CT could explain the lack of association with other STIs. The associations observed with NG could be the result of high-risk sexual networks or lack of protective immunity. Risk factors for CT and NG are distinct and may differ geographically, which should be considered when developing diagnostic tools or guiding presumptive treatment in specific populations.

Early antiretroviral therapy and daily pre-exposure prophylaxis for HIV prevention among female sex workers in Cotonou, Benin: a prospective observational demonstration study

INTRODUCTION

In sub-Saharan Africa, HIV prevalence remains high, especially among key populations. In such situations, combination prevention including clinical, behavioural, structural and biological components, as well as adequate treatment are important. We conducted a demonstration project at the Dispensaire IST, a clinic dedicated to female sex workers (FSWs) in Cotonou, on early antiretroviral therapy (E-ART, or immediate "test-and-treat") and pre-exposure prophylaxis (PrEP). We present key indicators such as uptake, retention and adherence.

METHODS

In this prospective observational study, we recruited FSWs from October 4th 2014 to December 31st 2015 and followed them until December 31st 2016. FSWs were provided with daily tenofovir disoproxil fumarate/emtricitabine (Truvada® ) for PrEP or received a first-line antiretroviral regimen as per Benin guidelines. We used generalized estimating equations to assess trends in adherence and sexual behaviour.

RESULTS

Among FSWs in the catchment area, HIV testing coverage within the study framework was 95.5% (422/442). At baseline, HIV prevalence was 26.3% (111/422). Among eligible FSWs, 95.5% (105/110) were recruited for E-ART and 88.3% (256/290) for PrEP. Overall retention at the end of the study was 59.0% (62/105) for E-ART and 47.3% (121/256) for PrEP. Mean (±SD) duration of follow-up was 13.4 (±7.9) months for E-ART and 11.8 (±7.9) months for PrEP. Self-reported adherence was over 90% among most E-ART participants. For PrEP, adherence was lower and the proportion with 100% adherence decreased over time from 78.4% to 56.7% (p-trend < 0.0001). During the 250.1 person-years of follow-up among PrEP initiators, two seroconversions occurred (incidence 0.8/100 person-years (95% confidence interval: 0.3 to 1.9/100 person-years)). The two seroconverters had stopped using PrEP for at least six months before being found HIV-infected. In both groups, there was no evidence of reduced condom use.

CONCLUSIONS

This study provides data on key indicators for the integration of E-ART and PrEP into the HIV prevention combination package already offered to FSWs in Benin. PrEP may be more useful as an individual intervention for adherent FSWs rather than a specific public health intervention. E-ART was a more successful intervention in terms of retention and adherence and is now offered to all key populations in Benin.

STUDY REGISTRATION

ClinicalTrials.gov NCT02237.