Efficacy of assisted partner services for people who inject drugs in Kenya to identify partners living with HIV and hepatitis C virus infection: a prospective cohort study

BACKGROUND

People who inject drugs are at increased risk of both HIV and hepatitis C virus (HCV) infections but face barriers to testing and engagement in care. Assisted partner services are effective in locating people with HIV but are understudied among people who inject drugs. We assessed whether assisted partner services could be used to find, test for HIV and HCV infections, and link to care the partners of people who inject drugs in Kenya.

METHODS

In this prospective study at eight sites offering harm-reduction services in Kenya, we enrolled people aged 18 years or older who inject drugs and were living with HIV (index participants) between Feb 27, 2018, and Nov 1, 2021. Index participants provided information about their sexual and injecting partners (ie, anyone with whom they had had sexual intercourse or injected drugs in the previous 3 years), and then community-embedded peer educators located partners and referred them for enrolment in the study (partner participants). All participants underwent testing for HCV infection, and partner participants also underwent HIV testing. Index and partner participants with HIV but who were not on antiretroviral therapy (ART) were linked with treatment services, and those positive for HCV were linked to treatment with direct-acting antivirals. We calculated the number of index participants whom we needed to interview to identify partner participants with HIV and HCV infection.

FINDINGS

We enrolled 989 people living with HIV who inject drugs, who mentioned 4705 sexual or injecting partners. Of these 4705 partners, we enrolled 4597 participants, corresponding to 3323 unique individuals. 597 (18%) partner participants had HIV, of whom 506 (85%) already knew their status. 358 (71%) of those who knew they were HIV positive were virally suppressed. 393 (12%) partner participants were HCV antibody positive, 213 (54%) of whom had viraemia and 104 (26%) of whom knew their antibody status. 1·66 (95% CI 1·53-1·80) index participants had to be interviewed to identify a partner with HIV, and 4·24 (3·75-4·85) had to be interviewed to find a partner living with HIV who was unaware of their HIV status, not on ART, or not virally suppressed. To find a partner seropositive for HCV who did not know their antibody status, 3·47 (3·11-3·91) index participants needed to be interviewed. Among the 331 index and partner participants living with HIV who were not on ART at enrolment, 238 (72%) were taking ART at 6-month follow-up. No adverse events were attributed to study procedures.

INTERPRETATION

Use of assisted partner services among people with HIV who inject drugs was safe and identified partners with HIV and HCV infections. Assisted partner services was associated with increased uptake of ART for both index participants and partners.

FUNDING

US National Institutes of Health.

Assessing awareness and use of HIV self-testing kits after the introduction of a community-based HIV self-testing programme among men who have sex with men in Kenya

Men who have sex with men (MSM) bear a disproportionate burden of new HIV infections in Kenya, while experiencing discrimination, leading to suboptimal levels of HIV care. HIV self-testing (HIVST) is a tool to increase HIV screening and earlier diagnosis; however, questions remain regarding how best to scale-up HIVST to MSM in Kenya. The main objective of this study was to examine changes in knowledge and use of HIVST after implementation of a community-led HIVST project. Participants were MSM recruited from Kisumu, Mombasa, and Kiambu counties. Data were collected from two rounds (Round 1: 2019; Round 2: 2020) of serial cross-sectional integrated biological and behavioural assessments (IBBA), pre-, and post-project implementation. Two main outcomes were measured: 1) whether the respondent had ever heard of HIVST; and 2) whether they had ever used HIVST kits. Changes in outcomes between IBBA rounds were examined using modified multivariable Poisson regression models; adjusted prevalence ratios (aPR) and 95% confidence intervals (95% CI) are reported. A total of 2,328 respondents were included in main analyses. The proportion of respondents who had heard of HIVST increased from 75% in Round 1 to 94% in Round 2 (aPR: 1.2, 95% CI: 1.2-1.3), while those reporting using an HIVST kit increased from 20% to 53% (aPR: 2.3, 95% CI: 2.0-2.6). Higher levels of education and HIV programme awareness were associated with both outcomes. Awareness and use of HIVST kits increased after implementation of a community-led HIVST implementation project, demonstrating the importance of integration with existing community groups.

Changes in context, typology and programme outcomes between early and recent periods of sex work among young female sex workers in Mombasa, Kenya: A cross-sectional study

INTRODUCTION

The sex work context and typology change continuously and influence HIV related risk and vulnerability for young female sex workers (YFSW). We sought to describe changes in the context and typology of sex work between the first (early) and past month (recent) of sex work among YFSW to inform HIV prevention programming for sex workers.

METHODS

We used data from a cross-sectional survey (April-November 2015), administered using physical location-based sampling to 408 cis-women, aged 14-24 years, who self-identified as sex workers, in Mombasa, Kenya. We collected self-reported data on the early and recent month of sex work. The analysis focused on changes in a) sex work context and typology (defined by setting where sex workers practice sex work) where YFSW operated, b) primary typology of sex work, and c) HIV programme outcomes among YFSW who changed primary typology, within the early and recent month of sex work. We analysed the data using a) SPSS27.0 and excel; b) bivariate analysis and χ2 test; and c) bivariate logistic regression models.

RESULTS

Overall, the median age of respondents was 20 years and median duration in sex work was 2 years. Higher proportion of respondents in the recent period managed their clients on their own (98.0% vs. 91.2%), had sex with >5 clients per week (39.3% vs.16.5%); were able to meet > 50% of living expenses through sex work income (46.8% vs. 18.8%); and experienced police violence in the past month (16.4% vs. 6.5%). YFSW reported multiple sex work typology in early and recent periods. Overall, 37.2% reported changing their primary typology. A higher proportion among those who used street/ bus stop typology, experienced police violence, or initiated sex work after 19 years of age in the early period reported a change. There was no difference in HIV programme outcomes among YFSW who changed typology vs. those who did not.

CONCLUSIONS

The sex work context changes even in a short duration of two years. Hence, understanding these changes in the early period of sex work can allow for development of tailored strategies that are responsive to the specific needs and vulnerabilities of YFSW.

HIV acquisition prior to entry into formal sex work: inference from next-generation viral sequencing

OBJECTIVE

To infer the timing of HIV acquisition in relation to self-reported events in the sexual life course of adolescent girls and young women (AGYW) who self-identify as female sex workers (FSW) in Mombasa, Kenya.

DESIGN

Next-generation viral sequencing of samples of AGYW living with HIV in the Transitions study, a cross-sectional bio-behavioural survey of AGYW aged 14-24 years in Mombasa, Kenya.

METHOD

Dried blood spot specimens were collected from study participants ( n  = 37, all FSW). A portion of the HIV pol gene was sequenced using an in-house next-generation sequencing assay for HIV drug resistance mutation genotyping. Estimated time since infection (ETI) was inferred using the HIV EVO web-based tool ( https://hiv.biozentrum.unibas.ch/ETI/ ), and data on self-reported events were obtained from the survey.

RESULTS

The median ETI among FSW was 3.4 (interquartile range = 1.7, 6.3) years, with a median ETI of 1.5 years prior to entry into formal sex work. We estimated that 74.1% (95% confidence interval = 53.7-88.9%) of participants living with HIV and who self-identified as FSW likely acquired HIV prior to self-identification as a sex worker.

CONCLUSIONS

Findings suggest a large fraction of prevalent HIV infection among AGYW engaged in sex work stems from acquisition prior to entry into formal sex work. Current HIV prevention programs tailored for sex workers may miss key opportunities for HIV prevention as they are designed to reach women after entry into formal sex work, signaling a need for tailored programs to reach high-risk AGYW earlier on in their sexual life course.

Predictors of hepatitis C cure among people who inject drugs treated with directly observed therapy supported by peer case managers in Kenya

BACKGROUND & AIMS

Directly observed therapy (DOT) maximizes adherence and minimizes treatment gaps. Peer case managers (PCM) have also shown promise as a component of integrated HCV treatment strategies. DOT and PCM-support have been underexplored, particularly in low- and middle-income countries (LMICs). The objective of this study was to evaluate predictors of sustained virologic response (SVR) among people who inject drugs (PWID) attending medication-assisted treatment (MAT) and needle and syringe programs (NSP) sites in Kenya.

METHODS

We recruited PWID accessing MAT and NSP in Nairobi and Coastal Kenya. PWID were treated with ledipasvir/sofosbuvir using DOT supported by PCMs. We used bivariate and multivariate logistic regression to examine the impact of sociodemographic, behavioral, and clinical factors on SVR.

RESULTS

Among 92 PWID who initiated HCV treatment, 79 (86%) were male with mean age of 36.3 years (SD=±6.5); 38 (41%) were HIV-positive, and 87 (95%) reported injecting drugs in the last 30 days. Just over half of participants were genotype 1a (55%), followed by genotype 4a (41%) and mixed 1a/4a (3%). Most participants, 85 (92%) completed treatment and 79 (86%) achieved SVR. While sociodemographic and behavioral factors including recent injection drug use were not significantly associated with achieving SVR, being fully adherent (p=0.042), number of doses taken (p=0.008) and treatment completion (p= 0.001) were associated with higher odds of achieving SVR.

CONCLUSIONS

DOT with PCM-support was an effective model for HCV treatment among PWID in this LMIC setting. Adherence was the most important driver of SVR suggesting DOT and PCM support can overcome other factors that might limit adherence. Further research is necessary to ascertain the effectiveness of other models of HCV care for PWID in LMICs given NSP and MAT access is variable, and DOT may not be sustainable with limited resources.

Challenges and best practices for hepatitis C care among people who inject drugs in resource limited settings: focus group discussions with healthcare providers in Kenya

People who inject drugs (PWID) living with Hepatitis C (HCV) in low- and middle-income countries face substantial barriers to HCV care. We sought to gain healthcare providers' perspectives on challenges and best practices for HCV care provision among PWID in Kenya. We conducted three focus group discussions (FGD) with 23 healthcare providers working with PWID living with HCV in Nairobi and Mombasa. Transcribed interviews were analysed thematically. Overarching themes regarding HCV prevention and treatment were: (1) lack of HCV-related knowledge at the provider and patient levels; (2) stigmatisation of people living with HCV and PWID; and (3) difficulties among PWID with navigating the healthcare system. Some providers suggested systematically integrating HCV care into existing PWID-specific harm reduction programs to improve HCV care provision as well as creating national HCV guidelines to guide clinicians. This study highlights the need for national HCV treatment guidelines and increased public HCV education, as well as culturally sensitive models integrating HCV care into programs PWID are already accessing. These strategies will be useful in improving access to HCV care among PWID and has the potential to decrease HCV transmission and prevalence among this vulnerable population.

Occupational roles and risks of community-embedded peer educators providing HIV, hepatitis C and harm reduction services to persons who inject drugs in Nairobi, Kenya

BACKGROUND

In Kenya, harm reduction organizations have adopted evidence-based peer educator (PE) programs, where former people who inject drugs (PWID) serve as community health liaisons to engage PWID in HIV, HCV and harm reduction services. While PEs play an integral role in healthcare delivery, little data exists on their roles, risks and experiences working with PWID, which may be used to inform local harm reduction policy.

METHODS

PE's from two harm reduction sites in Nairobi were randomly and purposively selected to participate in semi-structured in-depth interviews. Thematic analysis was conducted to characterize the expected versus actual roles that PEs employ while serving PWID, personal motivation and/or challenges and occupational health risks. Data was analyzed using Atlas.ti software.

RESULTS

Twenty PEs participated in the study. On average, PEs were 37 years of age, with 3 years of service. Female representation was 30%. Expected responsibilities included locating clients, establishing rapport, educating and escorting clients to addiction care facilities. Additional roles included attending to clients outside of work hours, escorting clients to medical appointments and facilitating patient-provider discussions. Occupational health risks included harassment by police and drug dealers, needle sticks, and close proximity to drug use environments that could prompt drug relapse. Despite these challenges and risks, PEs are motivated by their personal experiences of overcoming addiction with help from harm reduction programs.

CONCLUSIONS/RECOMMENDATIONS

PEs play a vital role in HIV, HCV and harm reduction service delivery in Kenya, often exceeding their job descriptions by offering additional support to PWID. Recommendations include (1) advocating for PEs to provide patient navigation services, (2) promoting the use of post-exposure prophylaxis (PEP), (3) providing occupational mental health services to prevent drug relapse, and (4) collaborating with law enforcement to address harassment, with the ultimate goal of reducing HIV and HCV incidence among PWID.

Modelling the impact of HIV and hepatitis C virus prevention and treatment interventions among people who inject drugs in Kenya

OBJECTIVES

People who inject drugs (PWID) in Kenya have high HIV (range across settings: 14-26%) and hepatitis C virus (HCV; 11-36%) prevalence. We evaluated the impact of existing and scaled-up interventions on HIV and HCV incidence among PWID in Kenya.

DESIGN

HIV and HCV transmission model among PWID, calibrated to Nairobi and Kenya's Coastal region.

METHODS

For each setting, we projected the impact (percent of HIV/HCV infections averted in 2020) of existing coverages of antiretroviral therapy (ART; 63-79%), opioid agonist therapy (OAT; 8-13%) and needle and syringe programmes (NSP; 45-61%). We then projected the impact (reduction in HIV/HCV incidence over 2021-2030), of scaling-up harm reduction [Full harm reduction ('Full HR'): 50% OAT, 75% NSP] and/or HIV (UNAIDS 90-90-90) and HCV treatment (1000 PWID over 2021-2025) and reducing sexual risk (by 25/50/75%). We estimated HCV treatment levels needed to reduce HCV incidence by 90% by 2030.

RESULTS

In 2020, OAT and NSP averted 46.0-50.8% (range of medians) of HIV infections and 50.0-66.1% of HCV infections, mostly because of NSP. ART only averted 12.9-39.8% of HIV infections because of suboptimal viral suppression (28-48%). Full HR and ART could reduce HIV incidence by 51.5-64% and HCV incidence by 84.6-86.6% by 2030. Also halving sexual risk could reduce HIV incidence by 68.0-74.1%. Alongside full HR, treating 2244 PWID over 2021-2025 could reduce HCV incidence by 90% by 2030.

CONCLUSION

Existing interventions are having substantial impact on HIV and HCV transmission in Kenya. However, to eliminate HIV and HCV, further scale-up is needed with reductions in sexual risk and HCV treatment.

Programmatic mapping and estimating the population size of female sex workers, men who have sex with men, people who inject drugs and transgender populations in Kenya

Introduction: Effective coverage of Human Immunodeficiency Virus prevention services for Key Populations (KPs) including female sex workers (FSWs), men who have sex with men (MSM), people who inject drugs (PWID) and transgender (TG) people necessitates periodic validation of physical venues and size estimates. Kenya conducted a robust size estimation of KPs in 2012 and a repeat mapping and size estimation exercise was conducted in 2018 to update KP Size Estimates and sub-typologies within each County for calculation of realistic program indicators.  Methods: A prospective mixed methods programmatic mapping approach adopted comprised two steps. The first step involved consolidating and documenting all known venues where KPs congregate while the second step included visiting and validating these venues confirming their active status. Data were collected in 34 out of 47 Counties in Kenya between January and March 2018. Data collected included estimated number of KPs (range), venue typology and timing of operation of each venue.   Results: We estimated a total number of 167,940 (129,271 to 206,609) FSWs; 32,580 (24,704 to 40,455) MSM; 16,063 (12,426 to 19,691) PWIDs; 10,951 (8,160 to 13,742) and 4,305 (2,826 to 5,783) transgender people congregating at 10,250, 1,729, 401 and 1,202 venues respectively. Majority of the venues for FSW (81%), MSM (64%) and transgender people (67%) were bars with and without lodging, PWIDs were mostly found on streets and injecting dens (70%).  Around 9% of FSW and MSM and11% of PWIDs were below the age of 18 years.  Conclusion: This study provided information on young KPs, female PWIDs, MSWs and for the first time, TG people in Kenya. The exercise updated size estimates of KPs by typology and provided new evidence for resource allocation, planning of interventions and targets. Programmatic mapping continues to be a useful approach supporting programs to achieve high levels of coverage and prioritize resources.

HIV prevention programme with young women who sell sex in Mombasa, Kenya: learnings for scale-up

Introduction

In 2018, the National AIDS and sexually transmitted infection (STI) Control Programme developed a national guidelines to facilitate the inclusion of young women who sell sex (YWSS) in the HIV prevention response in Kenya. Following that, a 1‐year pilot intervention, where a package of structural, behavioural and biomedical services was provided to 1376 cisgender YWSS to address their HIV‐related risk and vulnerability, was implemented.

Methods

Through a mixed‐methods, pre/post study design, we assessed the effectiveness of the pilot, and elucidated implementation lessons learnt. The three data sources used included: (1) monthly routine programme monitoring data collected between October 2019 and September 2020 to assess the reach and coverage; (2) two polling booth surveys, conducted before and after implementation, to determine the effectiveness; and (3) focus group discussions and key informant interviews conducted before and after intervention to assess the feasibility of the intervention. Descriptive analysis was performed to produce proportions and comparative statistics.

Results

During the intervention, 1376 YWSS were registered in the programme, 28% were below 19 years of age and 88% of the registered YWSS were active in the last month of intervention. In the survey, respondents reported increases in HIV‐related knowledge (61.7% vs. 90%, p <0.001), ever usage of pre‐exposure prophylaxis (8.5% vs. 32.2%, p < 0.001); current usage of pre‐exposure prophylaxis (5.3% vs. 21.1%, p<0.002); ever testing for HIV (87.2% vs. 95.6%, p <0.04) and any clinic visit (35.1 vs. 61.1, p <0.001). However, increase in harassment by family (11.7% vs. 23.3%, p<0.04) and discrimination at educational institutions (5.3% vs. 14.4%, p<0.04) was also reported. In qualitative assessment, respondents reported early signs of success, and identified missed opportunities and made recommendations for scale‐up.

Conclusions

Our intervention successfully rolled out HIV prevention services for YWSS in Mombasa, Kenya, and demonstrated that programming for YWSS is feasible and can effectively be done through YWSS peer‐led combination prevention approaches. However, while reported uptake of treatment and prevention services increased, there was also an increase in reported harassment and discrimination requiring further attention. Lessons learnt from the pilot intervention can inform replication and scale‐up of such interventions in Kenya.

Hepatitis C treatment outcomes among people who inject drugs accessing harm reduction settings in Kenya

Data are limited on HCV treatment outcomes among people who inject drugs (PWID) in low- and middle-income countries (LMICs) and particularly sub-Saharan Africa. We provided ledipasvir/sofosbuvir under directly observed therapy (DOT) to 95 PWID accessing medication-assisted treatment (MAT) and needle and syringe programs (NSP) in Nairobi and Coastal Kenya. Participants were predominantly male (n=81, 85.3%), mean age of 36.5 years (SD=±6.5); 38 (40%) were HIV-positive, 12 (12.6%) were cirrhotic, and 87 (91.6%) reported injecting drugs in the last 30 days. Genotypes were 53 (55.8%) 1a, 39 (41.1%) 4a, and 3 (3.2%) 1a/4a. Among 92 who initiated treatment, 85 (92.4%) completed treatment and 79 (85.9%) achieved SVR. In conclusion, HCV treatment among PWID in an LMIC setting is feasible. Further research is necessary to ascertain optimal models of HCV care given NSP and MAT access is variable in LMICs, and DOT may not be sustainable with limited resources.

Impact of COVID-19 on substance use disorder treatment services in Kenya: Qualitative findings from healthcare providers

BACKGROUND

People who inject drugs are at an increased risk for contracting SARS-CoV-2 and have experienced barriers to accessing harm reduction services during the COVID-19 pandemic. Understanding how to best provide these services is essential for COVID-19 mitigation. The goal of this study was to ascertain challenges and successes for caring for people who inject drugs in Kenya during the COVID-19 pandemic.

METHODS

We conducted focus group discussions and one-on-one key informant interviews with healthcare providers who work with people who inject drugs in Kenya. Interviews explored how COVID-19 and social distancing measures impacted service provision, as well as what strategies were used to overcome these barriers. We used thematic analysis to analyze transcribed interviews.

RESULTS

Participants included 29 service providers from 11 healthcare professions at three medication assisted treatment (MAT) and four drop-in center (DIC) sites (N=15 males and N=14 females, with an average age of 35 years). Four overarching themes emerged in our thematic analysis in which providers described both barriers to providing care and solutions to overcome them: (1) COVID-19-related misconceptions; (2) Limited COVID-19 testing and screening; (3) Structural changes related to service provision; and (4) Access to material resources such as meals, needle and syringe program kits, and personal protective equipment.

CONCLUSIONS

Our findings demonstrate the COVID-19 pandemic-imposed challenges for substance use disorder treatment providers and patients, however with ingenuity many of these challenges were able to be overcome.

Validity and reliability of the Neilands sexual stigma scale among Kenyan gay, bisexual, and other men who have sex with men

Background

We evaluated the validity and reliability of the Neilands sexual stigma scale administered to 871 gay, bisexual, and other men who have sex with men (GBMSM) at two research locations in Kenya.

Methods

Using cross-validation, exploratory factor analysis (EFA) was performed on a randomly selected subset of participants and validated using confirmatory factor analysis (CFA) on the remaining participants. Associations of the initial and final stigma scale factors with depressive symptoms, alcohol use, and other substance use were examined for the entire dataset.

Results

EFA produced a two-factor scale of perceived and enacted stigma. The CFA model fit to the two-factor scale was improved after removing three cross-loaded items and adding correlated errors (chi-squared = 26.5, df 17, p = 0.07). Perceived stigma was associated with depressive symptoms (beta = 0.34, 95% CI 0.24, 0.45), alcohol use (beta = 0.14, 95% CI 0.03, 0.25) and other substance use (beta = 0.19, 95% CI 0.07, 0.31), while enacted stigma was associated with alcohol use (beta = 0.17, 95% CI 0.06, 0.27).

Conclusions

Our findings suggest enacted and perceived sexual stigma are distinct yet closely related constructs among GBMSM in Kenya and are associated with poor mental health and substance use.

Understanding socio-sexual networks: critical consideration for HIVST intervention planning among men who have sex with men in Kenya

BACKGROUND

HIV self-testing (HIVST) has emerged as a way of reaching individuals who may be less likely to access testing, including men who have sex with men (MSM). Understanding the social networks of MSM is key to tailoring interventions, such as HIVST, for particular locations.

METHODS

We undertook a socio-sexual network study to characterize and identify patterns of connection among MSM and inform an HIVST intervention in three sites in Kenya. Community researchers in each site selected eight seeds to complete a demographic form and network surveys for 15 each of their sexual and social network members. Seeds recruited three respondents, including two regular service users and one MSM who was "unreached" by the program, who then each identified three respondents, resulting with data on 290 individuals.

RESULTS

Findings illustrate the interconnectedness of community-based organization (CBO) members and non-members. In networks where a majority of members had a CBO membership, members had better contacts with programs and were more likely to have accessed health services. Larger networks had more HIV testing and seeds with frequent testing had a positive influence on their network members also being tested frequently. HIVST was tried in very few networks. Almost all network members were willing to use HIVST.

CONCLUSION

Willingness to use HIVST was nearly universal and points to the importance of networks for reaching individuals not enrolled in programs. Network analysis can help in understanding which type of networks had higher testing and how network-based approaches can be useful to promote HIVST in certain contexts.

Remaking the Technosubject: Kenyan Men Contextualizing HIV Self-Testing Technologies

The Kenyan government offers free HIV self-testing kits to men who have sex with men. The value of self-testing is based on the imaginary of an autonomous technosubject empowered to independently control testing services, thereby "freed," through technology, from the social conditions that might inhibit health services utilization. Following a community-centered collaborative approach, community researchers interviewed their peers who examined and reacted to the technology. Participants reframed the technosubject as intertwined with the social world and the testing kit itself as an object that exerts agency and possesses affective potential. Attending to these socio-material relationalities offers insights into program planning.

An intensive model of care for hepatitis C virus screening and treatment with direct-acting antivirals in people who inject drugs in Nairobi, Kenya: a model-based cost-effectiveness analysis

BACKGROUND AND AIMS

Hepatitis C virus (HCV) treatment is essential for eliminating HCV in people who inject drugs (PWID), but has limited coverage in resource-limited settings. We measured the cost-effectiveness of a pilot HCV screening and treatment intervention using directly observed therapy among PWID attending harm reduction services in Nairobi, Kenya.

DESIGN

We utilized an existing model of HIV and HCV transmission among current and former PWID in Nairobi to estimate the cost-effectiveness of screening and treatment for HCV, including prevention benefits versus no screening and treatment. The cure rate of treatment and costs for screening and treatment were estimated from intervention data, while other model parameters were derived from literature. Cost-effectiveness was evaluated over a life-time horizon from the health-care provider's perspective. One-way and probabilistic sensitivity analyses were performed.

SETTING

Nairobi, Kenya.

POPULATION

PWID.

MEASUREMENTS

Treatment costs, incremental cost-effectiveness ratio (cost per disability-adjusted life year averted).

FINDINGS

The cost per disability-adjusted life-year averted for the intervention was $975, with 92.1% of the probabilistic sensitivity analyses simulations falling below the per capita gross domestic product for Kenya ($1509; commonly used as a suitable threshold for determining whether an intervention is cost-effective). However, the intervention was not cost-effective at the opportunity cost-based cost-effectiveness threshold of $647 per disability-adjusted life-year averted. Sensitivity analyses showed that the intervention could provide more value for money by including modelled estimates for HCV disease care costs, assuming lower drug prices ($75 instead of $728 per course) and excluding directly-observed therapy costs.

CONCLUSIONS

The current strategy of screening and treatment for hepatitis C virus (HCV) among people who inject drugs in Nairobi is likely to be highly cost-effective with currently available cheaper drug prices, if directly-observed therapy is not used and HCV disease care costs are accounted for.

Participation in methadone programs improves antiretroviral uptake and HIV viral suppression among people who inject drugs in Kenya

BACKGROUND

HIV prevalence among people who inject drugs (PWID) in Kenya is estimated to be 18% compared to 4.5% in the general population. Studies from high-income countries have demonstrated that methadone use is associated with increased uptake of antiretroviral therapy (ART) and higher rates of viral suppression among PWID with HIV. However, it is unclear whether methadone use has the same effect among African PWID living with HIV.

METHODS

We performed a cross-sectional study to evaluate associations between methadone program participation and ART uptake and viral suppression (HIV RNA viral load <1000 copies/ml) among PWID with HIV in Kenya. Participants were recruited from needle and syringe programs and methadone clinics, interviewed on site, and samples were obtained and assayed for HIV viral loads. Univariate and multiple logistic regression were used to determine associations.

RESULTS

Among 679 participants, median age was 37 years, 48% were female, and 24% were in a methadone program. We observed higher proportions of ART use (96% vs. 87%, p = 0.001) and HIV viral suppression (78% vs. 65%, p = 0.012) among PWID on methadone compared to those not on methadone treatment. PWID who were not participating in a methadone program were 3-fold more likely to be off ART and approximately twice as likely to be viremic compared to those in methadone programs (adjusted odds ratio [aOR] = 3.35, 95% confidence interval [CI]: 1.35-8.35 and aOR = 1.90, 95% CI: 1.03-3.52, respectively).

CONCLUSIONS

In this study, Kenyan PWID living with HIV participating in a methadone treatment program were more likely to be on ART and to have achieved viral suppression. Scale-up of methadone programs may have a positive impact on HIV epidemic control for this key population.

A decade and beyond: learnings from HIV programming with underserved and marginalized key populations in Kenya

INTRODUCTION

Key populations (KP) continue to account for high HIV incidence globally. Still, prioritization of KP in the national HIV prevention response remains insufficient, leading to their suboptimal access to HIV programmes. This commentary aims to share Kenya's challenges and successes in achieving 2020 global HIV targets and scaling up the KP programme in the last decade.

DISCUSSION

The KP programme in Kenya has scaled up in the last decade with the inclusion of female sex workers (FSW), men who have sex with men (MSM), people who inject drugs (PWID), transgender people and people in prisons as priority populations in the national HIV response. KP coverage based on official size estimates for FSW is 73%, for MSM is 82%, for PWID through needle syringe programme (NSP) is 71%, and through opioid substitution therapy (OST) is 26% and for transgender people is 5%. The service outcomes for KP have been relatively strong in prevention with high condom use at last paid sex for FSW (92%) and use of sterile equipment among PWID (88%), though condom use at last sex with a non-regular partner among MSM (78%) is still low. The KP programme has not met care continuum targets for all subpopulations with low case findings. The national KP programme led by the Ministry of Health has scaled up the programme through (a) strategic partnerships with KP-led and competent organizations, researchers and donors; (b) development of policy guidance and programme standards; (c) continuous sensitization and advocacy to garner support; (d) development of national reporting systems, among others. However, the programme is still struggling with uncertain size estimates; lack of updated bio-behavioural survey data; inadequate scale-up of interventions among transgender people and people in prison settings; gaps in reaching adolescent and young KP, and effectively addressing structural barriers like violence and stigma.

CONCLUSIONS

To reach the ambitious global HIV targets, sufficient coverage of KP with quality HIV programmes is critical. Despite scaling up the KP programme, Kenya has not yet achieved the 2020 global HIV targets and needs more efforts to scale-up quality programmes for KP who are underserved in the HIV response.

Peer-mediated HIV assisted partner services to identify and link to care HIV-positive and HCV-positive people who inject drugs: a cohort study protocol

INTRODUCTION

Targeted, tailored interventions to test high-risk individuals for HIV and hepatitis C virus (HCV) are vital to achieving HIV control and HCV microelimination in Africa. Compared with the general population, people who inject drugs (PWID) are at increased risk of HIV and HCV and are less likely to be tested or successfully treated. Assisted partner services (APS) increases HIV testing among partners of people living with HIV and improves case finding and linkage to care. We describe a study in Kenya examining whether APS can be adapted to find, test and link to HIV care the partners of HIV-positive PWID using a network of community-embedded peer educators (PEs). Our study also identifies HCV-positive partners and uses phylogenetic analysis to determine risk factors for onward transmission of both viruses.

METHODS

This prospective cohort study leverages a network of PEs to identify 1000 HIV-positive PWID for enrolment as index participants. Each index completes a questionnaire and provides names and contact information of all sexual and injecting partners during the previous 3 years. PEs then use a stepwise locator protocol to engage partners in the community and bring them to study sites for enrolment, questionnaire completion and rapid HIV and HCV testing. Outcomes include number and type of partners per index who are mentioned, enrolled, tested, diagnosed with HIV and HCV and linked to care.

ETHICS AND DISSEMINATION

Potential index participants are screened for intimate partner violence (IPV) and those at high risk are not eligible to enrol. Those at medium risk are monitored for IPV following enrolment. A community advisory board engages in feedback and discussion between the community and the research team. A safety monitoring board discusses study progress and reviews data, including IPV monitoring data. Dissemination plans include presentations at quarterly Ministry of Health meetings, local and international conferences and publications.

TRIAL REGISTRATION NUMBER

NCT03447210, Pre-results stage.

Sexual and reproductive health among adolescent girls and young women in Mombasa, Kenya

This secondary data analysis of a cross-sectional survey conducted in Mombasa, Kenya characterises sexual and reproductive health (SRH) indicators among adolescent girls and young women (AGYW) engaged in casual and transactional sexual relationships as well as sex work. It describes the association between awareness of local HIV programmes and SRH services uptake for AGYW engaged in sex work. Thirty-eight percent of the participants reported a history of pregnancy. Among participants not trying to get pregnant, 27% stated that they were not currently using any form of contraception. Of the participants who had an abortion, 59% were completed under unsafe conditions. For AGYW engaged in sex work, awareness of local HIV prevention programmes was associated with increased STI testing within the last year (29%) as well as at least one HIV test (99%) compared to those who were not aware of local programming (18% and 92%, respectively); however, only 26% of participants engaged in sex work had heard of local HIV prevention programmes. There were no associations between awareness of local HIV programming and rates of dual contraception use, safe abortion, most recent birth attended by a skilled health professional or testing for HIV during pregnancy. Our study found high need for SRH services, particularly, access to contraception and safe abortion. Continued efforts are required to improve access to the full spectrum of SRH interventions, including family planning services and access to safe abortion in addition to HIV prevention to promote health equity.

Hepatitis C-related knowledge, attitudes and perceived risk behaviours among people who inject drugs in Kenya: A qualitative study

Despite disproportionately high rates of Hepatitis C (HCV) among people who inject drugs (PWID) in low- and middle-income countries (LMICs), understanding of HCV-related knowledge, attitudes and perceived risk behaviours among this population remains limited. We aimed to elucidate knowledge, attitudes and experiences that could minimise transmission risk and maximise HCV treatment engagement among PWID in Kenya following the integration of HCV screening and education with needle and syringe programmes in drop-in-centres (DICs). We recruited 40 PWID with chronic HCV attending DICs in Nairobi and Coastal Kenya. Semi-structured interviews revealed a general understanding of HCV and awareness of HCV risk behaviours among participants; however, many felt limited control over their transmission risk due to factors such as 'local doctors', or individuals who perform a high volume of high-risk injections. Financial barriers, distance to clinic, poor health status and HCV-related stigma were all noted as barriers to HCV treatment. In conclusion, basic knowledge of and motivation for HCV treatment among PWID accessing DICs in Kenya was high; however, structural barriers and stigma complicate access to care. Local education programmes can address knowledge gaps, and behavioural and structural interventions can maximise the impact of HCV care in LMICs.

Mapping virtual platforms to estimate the population size of men who have sex with men (MSM) who use internet to find sexual partners: implications to enhance HIV prevention among MSM in Kenya

Introduction: Men who have sex with men (MSM) in Kenya face a disproportionate HIV disease burden. Over the last few years, the use of virtual platforms and internet sites to seek male sexual partners has increased manyfold in Kenya. New approaches are required to map, estimate and profile MSM who operate through virtual platforms to design interventions for them. Methods: This study was conducted in three counties in Kenya: Kiambu, Kisumu and Mombasa with MSM who use virtual platforms such as geosocial networking (GSN) and social networking applications to find and connect with male sex partners. The platforms were profiled through a multi-stage approach and the number of MSM associated with these platforms were estimated. In the final stage, 435 respondents randomly selected from the virtual platforms were interviewed in a secure location after informed consent. Data analysis focused on calculating an estimate of MSM for each virtual platform in each site, adjusting for duplicate profiles and multiple registrations. Results: We identified 24 GSN apps, 18 Facebook accounts/pages and 18 WhatsApp groups across the three counties, with Facebook being the preferred platform. Kiambu had the highest number of estimated MSM at 3,635 (95%CI = 3,335 to 3,990) followed by Kisumu at 1,567 (95%CI = 1,480 to 1,665) and Mombasa at 1,469 (95%CI = 1,335 to 1,604) who used virtual platforms to find other male sexual partners. On average, each MSM had 3.7 profiles on multiple platforms, with an average of 2.1 profiles used in the past month. Conclusions: The use of conventional population size estimation approaches that focus on physical sites alone may underestimate the total number of MSM in a geography. Virtual mapping should be used in conjunction with conventional hot spot based size estimation methodologies to estimate numbers of MSM to set programmatic targets.

HIV testing amid COVID-19: community efforts to reach men who have sex with men in three Kenyan counties

In comparison to European and American countries, Kenya has been less impacted by the COVID-19 pandemic in terms of reported cases and mortalities. However, everyday life has been dramatically affected by highly restrictive government-imposed measures such as stay-at-home curfews, prohibitions on mobility across national and county boundaries, and strict policing, especially of the urban poor, which has culminated in violence. This open letter highlights the effects of these measures on how three community-based organizations (CBOs) deliver HIV programs and services to highly stigmatized communities of men who have sex with men living in the counties of Kisumu, Kiambu and Mombasa. In particular, emphasis is placed on how HIV testing programs, which are supported by systematic peer outreach, are being disrupted at a time when global policymakers call for expanded HIV testing and treatment targets among key populations. While COVID 19 measures have greatly undermined local efforts to deliver health services to members and strengthen existing HIV testing programs, each of the three CBOs has taken innovative steps to adapt to the restrictions and to the COVID-19 pandemic itself. Although HIV testing in clinical spaces among those who were once regular and occasional program attendees dropped off noticeably in the early months of the COVID-19 lockdown, the program eventually began to rebound as outreach approaches shifted to virtual platforms and strategies. Importantly and unexpectedly, HIV self-testing kits proved to fill a major gap in clinic-based HIV testing at a time of crisis.

HIV testing amid COVID-19: community efforts to reach men who have sex with men in three Kenyan counties

In comparison to European and American countries, Kenya has been less impacted by the COVID-19 pandemic in terms of reported cases and mortalities. However, everyday life has been dramatically affected by highly restrictive government-imposed measures such as stay-at-home curfews, prohibitions on mobility across national and county boundaries, and strict policing, especially of the urban poor, which has culminated in violence. This open letter highlights the effects of these measures on how three community-based organizations (CBOs) deliver HIV programs and services to highly stigmatized communities of men who have sex with men living in the counties of Kisumu, Kiambu and Mombasa. In particular, emphasis is placed on how HIV testing programs, which are supported by systematic peer outreach, are being disrupted at a time when global policymakers call for expanded HIV testing and treatment targets among key populations. While COVID 19 measures have greatly undermined local efforts to deliver health services to members and strengthen existing HIV testing programs, each of the three CBOs has taken innovative steps to adapt to the restrictions and to the COVID-19 pandemic itself. Although HIV testing in clinical spaces among those who were once regular and occasional program attendees dropped off noticeably in the early months of the COVID-19 lockdown, the program eventually began to rebound as outreach approaches shifted to virtual platforms and strategies. Importantly and unexpectedly, HIV self-testing kits proved to fill a major gap in clinic-based HIV testing at a time of crisis.

Prevalence and patterns of gender-based violence across adolescent girls and young women in Mombasa, Kenya

Background

We sought to estimate the prevalence and describe heterogeneity in experiences of gender-based violence (GBV) across subgroups of adolescent girls and young women (AGYW).

Methods

We used data from a cross-sectional bio-behavioural survey among 1299 AGYW aged 14–24 in Mombasa, Kenya in 2015. Respondents were recruited from hotspots associated with sex work, and self-selected into one of three subgroups: young women engaged in casual sex (YCS), young women engaged in transactional sex (YTS), and young women engaged in sex work (YSW). We compared overall and across subgroups: prevalence of lifetime and recent (within previous year) self-reported experience of physical, sexual, and police violence; patterns and perpetrators of first and most recent episode of physical and sexual violence; and factors associated with physical and sexual violence.

Results

The prevalences of lifetime and recent physical violence were 18.0 and 10.7% respectively. Lifetime and recent sexual violence respectively were reported by 20.5 and 9.8% of respondents. Prevalence of lifetime and recent experience of police violence were 34.7 and 25.8% respectively. All forms of violence were most frequently reported by YSW, followed by YTS and then YCS. 62%/81% of respondents reported having sex during the first episode of physical/sexual violence, and 48%/62% of those sex acts at first episode of physical/sexual violence were condomless. In the most recent episode of violence when sex took place levels of condom use remained low at 53–61%. The main perpetrators of violence were intimate partners for YCS, and both intimate partners and regular non-client partners for YTS. For YSW, first-time and regular paying clients were the main perpetrators of physical and sexual violence. Alcohol use, ever being pregnant and regular source of income were associated with physical and sexual violence though it differed by subgroup and type of violence.

Conclusions

AGYW in these settings experience high vulnerability to physical, sexual and police violence. However, AGYW are not a homogeneous group, and there are heterogeneities in prevalence and predictors of violence between subgroups of AGYW that need to be understood to design effective programmes to address violence.

Mapping virtual platforms to estimate the population size of men who have sex with men (MSM) who use internet to find sexual partners: implications to enhance HIV prevention among MSM in Kenya

Introduction: Men who have sex with men (MSM) in Kenya face a disproportionate HIV disease burden. Over the last few years, the use of virtual platforms and internet sites to seek male sexual partners has increased manyfold in Kenya. New approaches are required to map, estimate and profile MSM who operate through virtual platforms to design interventions for them. Methods: This study was conducted in three counties in Kenya: Kiambu, Kisumu and Mombasa with MSM who use virtual platforms such as geosocial networking (GSN) and social networking applications to find and connect with male sex partners. The platforms were profiled through a multi-stage approach and the number of MSM associated with these platforms were estimated. In the final stage, 435 respondents randomly selected from the virtual platforms were interviewed in a secure location after informed consent. Data analysis focused on calculating an estimate of MSM for each virtual platform in each site, adjusting for duplicate profiles and multiple registrations. Results: We identified 24 GSN apps, 18 Facebook accounts/pages and 18 WhatsApp groups across the three counties, with Facebook being the preferred platform. Kiambu had the highest number of estimated MSM at 3,635 (95%CI = 3,335 to 3,990) followed by Kisumu at 1,567 (95%CI = 1,480 to 1,665) and Mombasa at 1,469 (95%CI = 1,335 to 1,604) who used virtual platforms to find other male sexual partners. On average, each MSM had 3.7 profiles on multiple platforms, with an average of 2.1 profiles used in the past month. Conclusions: The use of conventional population size estimation approaches that focus on physical sites alone may underestimate the total number of MSM in a geography. Virtual mapping should be used in conjunction with conventional hot spot based size estimation methodologies to estimate numbers of MSM to set programmatic targets.

Transitions: Novel Study Methods to Understand Early HIV Risk Among Adolescent Girls and Young Women in Mombasa, Kenya, and Dnipro, Ukraine

Transitions aims to understand the human immunodeficiency virus (HIV) risk at critical transition points in the sexual life course of adolescent girls and young women (AGYW) who engage in casual sex, transactional sex, and sex work. In this article, we present the Transitions study methods. The Transitions study has the following objectives: (1) to describe how the characteristics and length of the transition period and access gap vary across two epidemiological contexts (Mombasa, Kenya, and Dnipro, Ukraine); (2) to understand how the risk of HIV varies by length and characteristics of the transition period and access gap across epidemiologic contexts; and (3) to assess the extent to which HIV infections acquired during the transition period and access gap could mitigate the population-level impact of focused interventions for female sex workers and explore the potential marginal benefit of expanding programs to reach AGYW during the transition period and access gap. Cross-sectional biobehavioral data were collected from young women aged 14 to 24 years who were recruited from locations in Mombasa County, Kenya, and Dnipro, Ukraine, where sex work took place. Data are available for 1,299 Kenyan and 1,818 Ukrainian participants. The survey addressed the following areas: timing of transition events (first sex, first exchange of sex for money or other resources, self-identification as sex workers, entry into formal sex work, access to prevention program services); sexual behaviors (condom use, anal sex, sex under the influence of drugs or alcohol); partnerships (regular and first-time clients, regular and first-time transactional sex partners, and husbands and boyfriends); alcohol use; injection and non-injection illicit drug use; experience of violence; access to HIV prevention and treatment program; testing for sexually transmitted and blood-borne infections and HIV; and reproductive health (pregnancies, abortions, contraceptives). HIV and hepatitis C virus prevalence data were based on rapid test results. Mathematical modeling will be used to generate projections of onward HIV transmission at specific transition points in the sexual life course of AGYW. Taken together, these data form a novel data resource providing comprehensive behavioral, structural, and biological data on a high-risk group of AGYW in two distinct sociocultural and epidemiologic contexts.

HIV prevalence, testing and treatment among men who have sex with men through engagement in virtual sexual networks in Kenya: a cross-sectional bio-behavioural study

INTRODUCTION

In Kenya, men who have sex with men (MSM) are increasingly using virtual sites, including web-based apps, to meet sex partners. We examined HIV testing, HIV prevalence, awareness of HIV-positive status and linkage to antiretroviral therapy (ART), for HIV-positive MSM who solely met partners via physical sites (PMSM), compared with those who did so in virtual sites (either solely via virtual sites (VMSM), or via both virtual and physical sites (DMSM)).

METHODS

We conducted a cross-sectional bio-behavioural survey of 1200 MSM, 15 years and above, in three counties in Kenya between May and July 2019, using random sampling of physical and virtual sites. We classified participants as PMSM, DMSM and VMSM, based on where they met sex partners, and compared the following between groups using chi-square tests: (i) proportion tested; (ii) HIV prevalence and (iii) HIV care continuum among MSM living with HIV. We then performed multivariable logistic regression to measure independent associations between network engagement and HIV status.

RESULTS

177 (14.7%), 768 (64.0%) and 255 (21.2%), of participants were classified as PMSM, DMSM and VMSM respectively. 68.4%, 70.4% and 78.5% of PMSM, DMSM and VMSM, respectively, reported an HIV test in the previous six months. HIV prevalence was 8.5% (PMSM), 15.4% (DMSM) and 26.7% (VMSM), p < 0.001. Among those living with HIV, 46.7% (PMSM), 41.5% (DMSM) and 29.4% (VMSM) were diagnosed and aware of their status; and 40.0%, 35.6% and 26.5% were on antiretroviral treatment. After adjustment for other predictors, MSM engaged in virtual networks remained at a two to threefold higher risk of prevalent HIV: VMSM versus PMSM (adjusted odds ratio 3.88 (95% confidence interval (CI) 1.84 to 8.17) p < 0.001); DMSM versus PMSM (2.00 (95% CI 1.03 to 3.87), p = 0.040).

CONCLUSIONS

Engagement in virtual networks is associated with elevated HIV risk, irrespective of individual-level risk factors. Understanding the difference in characteristics among MSM-seeking partners in different sites will help HIV programmes to develop subpopulation-specific interventions.

Beyond biomedical and comorbidity approaches: Exploring associations between affinity group membership, health and health seeking behaviour among MSM/MSW in Nairobi, Kenya

We explored general health and psychosocial characteristics among male sex workers and other men who have sex with men in Nairobi, Kenya. A total of 595 MSM/MSW were recruited into the study. We assessed group differences among those who self-reported HIV positive (SR-HIVP) and those who self-reported HIV negative (SR-HIVN) and by affinity group membership. Quality of life among SR-HIVP participants was significantly worse compared to SR-HIVN participants. Independent of HIV status and affinity group membership, participants reported high levels of hazardous alcohol use, harmful substance use, recent trauma and childhood abuse. The overall sample exhibited higher prevalence of moderate to severe depressive symptoms compared to the general population. Quality of life among participants who did not report affinity group membership (AGN) was significantly worse compared to participants who reported affinity group membership (AGP). AGN participants also reported significantly lower levels of social support. Membership in affinity groups was found to influence health seeking behaviour. Our findings suggest that we need to expand the mainstay biomedical and comorbidity focused research currently associated with MSM/MSW. Moreover, there are benefits to being part of MSM/MSW organisations and these organisations can potentially play a vital role in the health and well-being of MSM/MSW.

Pre-exposure prophylaxis rollout in a national public sector program: the Kenyan case study

Background While advances have been made in HIV prevention and treatment, new HIV infections continue to occur. The introduction of pre-exposure prophylaxis (PrEP) as an additional HIV prevention option for those at high risk of HIV may change the landscape of the HIV epidemic, especially in sub-Saharan Africa, which bears the greatest HIV burden.

METHODS

This paper details Kenya's experience of PrEP rollout as a national public sector program. The process of a national rollout of PrEP guidance, partnerships, challenges, lessons learnt and progress related to national scale up of PrEP in Kenya, as of 2018, is described. National rollout of PrEP was strongly lead by the government, and work was executed through a multidisciplinary, multi-organisation dedicated team. This required reviewing available evidence, providing guidance to health providers, integration into existing logistic and health information systems, robust communication and community engagement. Mapping of the response showed that subnational levels had existing infrastructure but required targeted resources to catalyse PrEP provision. Rollout scenarios were developed and adopted, with prioritisation of 19 counties focusing on high incidence area and high potential PrEP users to maximise impact and minimise costs.

RESULTS

PrEP is now offered in over 900 facilities countrywide. There are currently over 14000 PrEP users 1 year after launching PrEP.

CONCLUSIONS

Kenya becomes the first African country to rollout PrEP as a national program, in the public sector. This case study will provide guidance for low- and middle-income countries planning the rollout of PrEP in response to both generalised and concentrated epidemics.

Evaluation of community-based HIV self-testing delivery strategies on reducing undiagnosed HIV infection, and improving linkage to prevention and treatment services, among men who have sex with men in Kenya: a programme science study protocol

BACKGROUND

HIV prevalence among men having sex with men (MSM) in Kenya is 18.2%. Despite scale-up of HIV testing services, many MSM remain unaware of their HIV status and thus do not benefit from accessing HIV treatment or prevention services. HIV self-testing (HIVST) may help address this gap. However, evidence is limited on how, when, and in what contexts the delivery of HIVST to MSM could increase awareness of HIV status and lead to early linkage to HIV treatment and prevention.

METHODS

The study will be embedded within existing MSM-focused community-based HIV prevention and treatment programmes in 3 counties in Kenya (Kisumu, Mombasa, Kiambu). The study is designed to assess three HIV testing outcomes among MSM, namely a) coverage b) frequency of testing and c) early uptake of testing. The study will adopt a mixed methods programme science approach to the implementation and evaluation of HIVST strategies via: (i) a baseline and endline bio-behavioural survey with 1400 MSM; (ii) a socio-sexual network study with 351 MSM; (iii) a longitudinal qualitative cohort study with 72 MSM; (iv) routine programme monitoring in three sites; (v) a programme-specific costing exercise; and (vi) mathematical modelling. This protocol evaluates the impact of community-based implementation of HIV self-testing delivery strategies among MSM in Kenya on reducing the undiagnosed MSM population, and time for linkage to prevention, treatment and care following HIV self-testing. Baseline data collection started in April 2019 and the endline data collection will start in July 2020.

DISCUSSION

This study is one of the first programme science studies in Sub-Saharan Africa exploring the effectiveness of integrating HIVST interventions within already existing HIV prevention and treatment programmes for MSM in Kenya at scale. Findings from this study will inform national best approaches to scale up HIVST among MSM in Kenya.

The disconnect between individual-level and population-level HIV prevention benefits of antiretroviral treatment

In 2019, the HIV pandemic is growing and soon over 40 million people will be living with HIV. Effective population-based approaches to decrease HIV incidence are as relevant as ever given modest reductions observed over the past decade. Treatment as prevention is often heralded as the path to improve HIV outcomes and to reduce HIV incidence. Although treatment of an individual does eliminate onward transmission to serodifferent partners (undetectable=untransmittable or U=U), population-level observational and experimental data have not shown a similar effect with scale-up of treatment on reducing HIV incidence. This disconnect might be the result of little attention given to heterogeneities of HIV acquisition and transmission risks that exist in people at risk for and living with HIV, even in the most broadly generalised epidemics. Available data suggest that HIV treatment is treatment, HIV prevention is prevention, and specificity of HIV treatment approaches towards people at highest risk of onward transmission drives the intersection between the two. All people living with HIV deserve HIV treatment, but both more accurately estimating and optimising the potential HIV prevention effects of universal treatment approaches necessitates understanding who is being supported with treatment rather than a focus on treatment targets such as 90-90-90 or 95-95-95.

Informing HIV Prevention Programs for Adolescent Girls and Young Women: A Modified Approach to Programmatic Mapping and Key Population Size Estimation

BACKGROUND

Standard programmatic mapping involves identifying locations where key populations meet, profiling of these locations (hotspots), and estimating the key population size. Information gained from this method has been used for HIV programming-resource allocation, program planning, service delivery, and monitoring and evaluation-for people who inject drugs, men who have sex with men, and female sex workers (FSWs). With an increasing focus on adolescent girls and young women (AGYW) as a priority population for HIV prevention, programs need to know the location of and how to effectively reach individuals who are at increased risk for HIV but were conventionally considered part of the general population. We hypothesize that AGYW who engage in transactional and casual sex also congregate at sex work hotspots to meet sex partners. Therefore, we adapted the standard programmatic mapping approach to understand the geographic distribution and population size of AGYW at increased HIV risk in Mombasa County, Kenya.

OBJECTIVES

The objectives are several-fold: (1) detail and compare the modified programmatic mapping approach used in this study to the standard approach, (2) estimate the number of young FSWs, (3) estimate the number of AGYW who congregate in sex work hotspots to meet sex partners other than clients, (4) estimate the overlap in sexual network in hotspots, (5) describe the distribution of sex work hotspots across Mombasa and its four subcounties, and (6) compare the distribution of hotspots that were known to the local HIV prevention program prior to this study and those newly identified.

METHODS

The standard programmatic mapping approach was modified to estimate the population of young women aged 14 to 24 years who visit sex work hotspots in Mombasa to meet partners for commercial, transactional, and casual sex.

RESULTS

We estimated that there were 11,777 FSWs (range 9265 to 14,290) in Mombasa in 2014 among whom 6127 (52.02%) were 14 to 24 years old. The population estimates for women aged 14 to 24 years who engaged in transactional and casual sex and congregated at the hotspots were 5348 (range 4185 to 6510) and 4160 (range 3194 to 5125), respectively. Of the 1025 validated sex work hotspots, 870 (84.88%) were locations also visited by women engaged in transactional and casual sex. Only 47 (4.58%) hotspots were exclusive sex work locations. The geographic and typological distribution of hotspots were significantly different between the four subcounties (P<.001). Of the 1025 hotspots, 419 (40.88%) were already known to the local HIV prevention program and 606 (59.12%) were newly identified.

CONCLUSIONS

Using the adapted programmatic mapping approach detailed in this study, our results show that HIV prevention programs tailored to AGYW can focus delivery of their interventions to sex work hotspots to reach subgroups that may be at increased risk for HIV.

Micro-planning at scale with key populations in Kenya: Optimising peer educator ratios for programme outreach and HIV/STI service utilisation

Peer education with micro-planning has been integral to scaling up key population (KP) HIV/STI programmes in Kenya since 2013. Micro-planning reinforces community cohesion within peer networks and standardizes programme inputs, processes and targets for outreach, including peer educator (PE) workloads. We assessed programme performance for outreach-in relation to the mean number of KPs for which one PE is responsible (KP:PE ratio)-and effects on HIV/STI service utilisation. Quarterly programmatic monitoring data were analysed from October 2013 to September 2016 from implementing partners working with female sex workers (FSWs) and men who have sex with men (MSM) across the country. All implementing partners are expected to follow national guidelines and receive micro-planning training for PEs with support from a Technical Support Unit for KP programmes. We examined correlations between KP:PE ratios and regular outreach contacts, condom distribution, risk reduction counselling, STI screening, HIV testing and violence reporting by KPs. Kenya conducted population size estimates (PSEs) of KPs in 2012. From 2013 to 2016, KP programmes were scaled up to reach 85% of FSWs (PSE 133,675) and 90% of MSM (PSE 18,460). Overall, mean KP:PE ratios decreased from 147 to 91 for FSWs, and from 79 to 58 for MSM. Lower KP:PE ratios, up to 90:1 for FSW and 60:1 for MSM, were significantly associated with more regular outreach contacts (p<0.001), as well as more frequent risk reduction counselling (p<0.001), STI screening (p<0.001) and HIV testing (p<0.001). Condom distribution and reporting of violence by KPs did not differ significantly between the two groups over all time periods. Micro-planning with adequate KP:PE ratios is an effective approach to scaling up HIV prevention programmes among KPs, resulting in high levels of programme uptake and service utilisation.

Changes in HIV prevention programme outcomes among key populations in Kenya: Data from periodic surveys

The Kenya National AIDS and STI Control Programme (NASCOP) conducted annual polling booth surveys (PBS) in 2014 and 2015 to measure outcomes from the national HIV prevention programme for key populations (KPs), comprising behavioural, biomedical and structural interventions. KPs included female sex workers (FSWs), men who have sex with men (MSM) and people who inject drugs (PWID). We compared survey results from the first and second rounds. Comparing the second to the first round, significantly more FSWs (93% vs. 88%, p<0.001) and MSM (77% vs. 58%, p<0.001) reported condom use at last sex with a paying client, and at last anal sex among MSM (80% vs. 77%, p<0.05) and PWID (48% vs. 27%, p<0.01). However, condom use with regular partners remained low, at less than 53% for FSWs and 69% for MSM. Among PWID, there was a significant increase in use of new needles and syringes at last injection (93% vs. 88%, p<0.001), and a significant decrease in reported non-availability of clean needles (23% vs. 36%, p<0.001). The number of overdoses in the past six months reduced significantly but remained high (40% vs. 51%, p<0.001). FSWs and MSM reported significantly higher HIV testing, and in all KP groups, over 93% reported ever having been tested for HIV. Among the respondents self-reporting to have tested HIV positive (24% of FSW, 22% of MSM and 19% of PWID), 80% of FSWs, 70% of MSM, and 73% of PWID reported currently taking antiretroviral therapy (ART). While the experience of forced intercourse by partners declined among FSWs (18% vs. 22%, p<0.01) and MSM (13% vs. 17%, p<0.01), more FSWs reported violence by law enforcement personnel (49% vs. 44%, p<0.001). These findings provide valuable information on the programme's progress, and a signpost for the integrated behavioural, biomedical and structural interventions to achieve their HIV prevention targets.

The contributions and future direction of Program Science in HIV/STI prevention

Background

Program Science is an iterative, multi-phase research and program framework where programs drive the scientific inquiry, and both program and science are aligned towards a collective goal of improving population health.

Discussion

To achieve this, Program Science involves the systematic application of theoretical and empirical knowledge to optimize the scale, quality and impact of public health programs. Program Science tools and approaches developed for strategic planning, program implementation, and program management and evaluation have been incorporated into HIV and sexually transmitted infection prevention programs in Kenya, Nigeria, India, and the United States.

Conclusion

In this paper, we highlight key scientific contributions that emerged from the growing application of Program Science in the field of HIV and STI prevention, and conclude by proposing future directions for Program Science.

Effects of exposure to an intensive HIV-prevention programme on behavioural changes among female sex workers in Nairobi, Kenya

While Kenya has had a long-standing national HIV-prevention programme, evidence on the level of exposure to its interventions and related effects on behavioural changes among female sex workers (FSWs) is limited. Using cross-sectional behavioural data collected in 2013 from 1 357 FSWs aged 18 years and above in Nairobi, Kenya, this study explores the relationship between FSW programme exposure levels and behavioural outcomes including condom use, sexually transmitted infection (STI)-treatment, and empowerment measures like disclosure of self-identity and violence reporting. We categorised programme exposure levels as none, moderate and intensive. Multivariate logistic regression was used for analysis. Overall, 35% of the FSWs were not exposed to any HIV prevention programme, whereas about 24% had moderate and 41% had intensive exposure. FSWs having intensive programme exposure had a higher likelihood of using condoms consistently with occasional clients (AOR: 1.57; 95% CI: 1.08-2.31) and seeking treatment for STIs (AOR: 3.37; 95% CI: 1.63-7.02) compared to FSWs with no or moderate exposure. Intensive programme exposure was also associated with higher self-disclosure of sex-work identity (AOR: 1.63; 95% CI: 1.19-2.24), reporting of violence to police (AOR: 2.45; 95% CI: 1.03-5.84), and negotiation of condom use at last sex when the client was under the influence of alcohol (AOR: 1.63; 95% CI: 0.94-2.82). Although HIV prevention programmes in Kenya have been underway for over a decade, programme efforts were largely focused on saturating the coverage (intervention breadth). Strategies should now focus on ensuring improved quality of contacts through intensified programme exposure (intervention depth) to enhance gains in behavioural change among FSWs and preventing the burden of HIV infection among them.

Healthcare provider perspectives on managing sexually transmitted infections in HIV care settings in Kenya: A qualitative thematic analysis

BACKGROUND

The burden of sexually transmitted infections (STIs) has been increasing in Kenya, as is the case elsewhere in sub-Saharan Africa, while measures for control and prevention are weak. The objectives of this study were to (1) describe healthcare provider (HCP) knowledge and practices, (2) explore HCP attitudes and beliefs, (3) identify structural and environmental factors affecting STI management, and (4) seek recommendations to improve the STI program in Kenya.

METHODS AND FINDINGS

Using individual in-depth interviews (IDIs), data were obtained from 87 HCPs working in 21 high-volume comprehensive HIV care centers (CCCs) in 7 of Kenya's 8 regions. Transcript coding was performed through an inductive and iterative process, and the data were analyzed using NVivo 10.0. Overall, HCPs were knowledgeable about STIs, saw STIs as a priority, reported high STI co-infection amongst people living with HIV (PLHIV), and believed STIs in PLHIV facilitate HIV transmission. Most used the syndromic approach for STI management. Condoms and counseling were available in most of the clinics. HCPs believed that having an STI increased stigma in the community, that there was STI antimicrobial drug resistance, and that STIs were not prioritized by the authorities. HCPs had positive attitudes toward managing STIs, but were uncomfortable discussing sexual issues with patients in general, and profoundly for anal sex. The main barriers to the management of STIs reported were low commitment by higher levels of management, few recent STI-focused trainings, high stigma and low community participation, and STI drug stock-outs. Solutions recommended by HCPs included formulation of new STI policies that would increase access, availability, and quality of STI services; integrated STI/HIV management; improved STI training; increased supervision; standardized reporting; and community involvement in STI prevention. The key limitations of our study were that (1) participant experience and how much of their workload was devoted to managing STIs was not considered, (2) some responses may have been subject to recall and social desirability bias, and (3) patients or clients of STI services were not interviewed, and therefore their inputs were not obtained. While considering these limitations, the number and variety of facilities sampled, the mix of staff cadres interviewed, the use of a standardized instrument, and the consistency of responses add strength to our findings.

CONCLUSIONS

This study showed that HCPs understood the challenges of, and solutions for, improving the management of STIs in Kenya. Commitment by higher management, training in the management of STIs, measures for reducing stigma, and introducing new policies of STI management should be considered by health authorities in Kenya.

Lessons learned from respondent-driven sampling recruitment in Nairobi: experiences from the field

BACKGROUND

Respondent-driven sampling (RDS) is used in a variety of settings to study hard-to-reach populations at risk for HIV and sexually transmitted infections. However, practices leading to successful recruitment among diverse populations in low-resource settings are seldom reported. We implemented the first, integrated, bio-behavioural surveillance survey among men who have sex with men, female sex workers and people who injected drugs in Nairobi, Kenya.

METHODS

The survey period was June 2010 to March 2011, with a target sample size of 600 participants per key populations. Formative research was initially conducted to assess feasibility of the survey. Weekly monitoring reports of respondent characteristics and recruitment chain graphs from NetDraw illustrated patterns and helped to fill recruitment gaps.

RESULTS

RDS worked well with men who have sex with men and female sex workers with recruitment initiating at a desirable pace that was maintained throughout the survey. Networks of people who injected drugs were well-integrated, but recruitment was slower than the men who have sex with men and female sex workers surveys.

CONCLUSION

By closely monitoring RDS implementation and conducting formative research, RDS studies can effectively develop and adapt strategies to improve recruitment and improve adherence to the underlying RDS theory and assumptions.

Risk Factors for HIV Acquisition in a Prospective Nairobi-Based Female Sex Worker Cohort

With two million new HIV infections annually, ongoing investigations of risk factors for HIV acquisition is critical to guide ongoing HIV prevention efforts. We conducted a prospective cohort analysis of HIV uninfected female sex workers enrolled at an HIV prevention clinic in Nairobi (n = 1640). In the initially HIV uninfected cohort (70 %), we observed 34 HIV infections during 1514 person-years of follow-up, i.e. an annual incidence of 2.2 % (95 % CI 1.6-3.1 %). In multivariable Cox Proportional Hazard analysis, HIV acquisition was associated with a shorter baseline duration of sex work (aHR 0.76, 95 % CI 0.63-0.91), minimum charge/sex act (aHR 2.74, 0.82-9.15, for low vs. intermediate; aHR 5.70, 1.96-16.59, for high vs. intermediate), N. gonorrhoeae infection (aAHR 5.89, 95 % CI 2.03-17.08), sex with casual clients during menses (aHR 6.19, 95 % CI 2.58-14.84), Depo Provera use (aHR 5.12, 95 % CI 1.98-13.22), and estimated number of annual unprotected regular partner contacts (aHR 1.004, 95 % CI 1.001-1.006). Risk profiling based on baseline predictors suggested that substantial heterogeneity in HIV risk is evident, even within a key population. These data highlight several risk factors for HIV acquisition that could help to re-focus HIV prevention messages.

Kenyan female sex workers' use of female-controlled nonbarrier modern contraception: do they use condoms less consistently?

OBJECTIVES

To examine whether nonbarrier modern contraceptive use is associated with less consistent condom use among Kenyan female sex workers (FSWs).

STUDY DESIGN

Researchers recruited 579 FSWs using respondent-driven sampling. We conducted multivariate logistic regression to examine the association between consistent condom use and female-controlled nonbarrier modern contraceptive use.

RESULTS

A total of 98.8% reported using male condoms in the past month, and 64.6% reported using female-controlled nonbarrier modern contraception. In multivariate analysis, female-controlled nonbarrier modern contraceptive use was not associated with decreased condom use with clients or nonpaying partners.

CONCLUSION

Consistency of condom use is not compromised when FSWs use available female-controlled nonbarrier modern contraception.

IMPLICATIONS

FSWs should be encouraged to use condoms consistently, whether or not other methods are used simultaneously.

Emerging themes for sensitivity training modules of African healthcare workers attending to men who have sex with men: a systematic review

Sensitivity training of front-line African health care workers (HCWs) attending to men who have sex with men (MSM) is actively promoted through national HIV prevention programming in Kenya. Over 970 Kenyan-based HCWs have completed an eight-modular online training free of charge (http://www.marps-africa.org) since its creation in 2011. Before updating these modules, we performed a systematic review of published literature of MSM studies conducted in sub-Saharan Africa (sSA) in the period 2011-2014, to investigate if recent studies provided: important new knowledge currently not addressed in existing online modules; contested information of existing module topics; or added depth to topics covered already. We used learning objectives of the eight existing modules to categorise data from the literature. If data could not be categorised, new modules were suggested. Our review identified 142 MSM studies with data from sSA, including 34 studies requiring module updates, one study contesting current content, and 107 studies reinforcing existing module content. ART adherence and community engagement were identified as new modules. Recent MSM studies conducted in sSA provided new knowledge, contested existing information, and identified new areas of MSM service needs currently unaddressed in the online training.

HIV and STI prevalence and injection behaviors among people who inject drugs in Nairobi: results from a 2011 bio-behavioral study using respondent-driven sampling

There is a dearth of evidence on injection drug use and associated HIV infections in Kenya. To generate population-based estimates of characteristics and HIV/STI prevalence among people who inject drugs (PWID) in Nairobi, a cross-sectional study was conducted with 269 PWID using respondent-driven sampling. PWID were predominantly male (92.5 %). An estimated 67.3 % engaged in at least one risky injection practice in a typical month. HIV prevalence was 18.7 % (95 % CI 12.3–26.7), while STI prevalence was lower [syphilis: 1.7 % (95 % CI 0.2–6.0); gonorrhea: 1.5 % (95 % CI 0.1–4.9); and Chlamydia: 4.2 % (95 % CI 1.2–7.8)]. HIV infection was associated with being female (aOR, 3.5; p = 0.048), having first injected drugs 5 or more years ago (aOR, 4.3; p = 0.002), and ever having practiced receptive syringe sharing (aOR, 6.2; p = 0.001). Comprehensive harm reduction programs tailored toward PWID and their sex partners must be fully implemented as part of Kenya’s national HIV prevention strategy.

Estimating the size of the female sex worker population in Kenya to inform HIV prevention programming

Background

The high burden of HIV infections among female sex workers (FSW) in sub-Saharan Africa has been long recognised, but effective preventive interventions have largely not been taken to scale. We undertook a national geographical mapping exercise in 2011/2012 to assess the locations and population size of FSW in Kenya, to facilitate targeted HIV prevention services for this population.

Methods and Findings

We used a geographical mapping approach, consisting of interviews with secondary key informants to identify “hot” spots frequented by FSW, their operational dynamics and the estimated numbers of FSW in those spots. This was followed by validation of the estimates through interviews with FSW at each spot identified. The mapping covered Nairobi, the capital city of Kenya, and 50 other major urban centres. In total, 11,609 secondary key informant interviews were conducted to identify FSW spots. Further, a total of 6,360 FSW were interviewed for spot validation purposes. A total of 10,670 spots where FSW congregate were identified. The estimated FSW population in all the towns mapped was 103,298 (range 77,878 to 128, 717). Size estimates in the towns mapped were extended to smaller towns that were not mapped, using a statistical model. The national urban FSW population estimate was 138,420 (range 107, 552 to 169, 288), covering all towns of over 5,000 population. We estimated that approximately 5% of the urban female population of reproductive age in Kenya could be sex workers, which is consistent with previous estimates from other sub-Saharan African countries.

Conclusions

This study provides the first national level data on the size of the FSW population in Kenya. These data can be used to enhance HIV prevention programme planning and implementation for FSW, to form the basis for impact evaluations, and to improve programme coverage by directing efforts to locations with the greatest need.

High HIV risk in a cohort of male sex workers from Nairobi, Kenya

OBJECTIVES

Men who have sex with men (MSM) are at high risk of HIV-1 acquisition and transmission, yet there remains limited data in the African context, and for men who sell sex to men (MSM SW) in particular.

METHODS

We enrolled 507 male sex workers in a Nairobi-based prospective cohort study during 2009-2012. All participants were offered HIV/STI screening, counselling and completed a baseline questionnaire.

RESULTS

Baseline HIV prevalence was 40.0% (95% CI 35.8% to 44.3%). Prevalent HIV infection was associated with age, less postsecondary education, marijuana use, fewer female partners and lower rates of prior HIV testing. Most participants (73%) reported at least two of insertive anal, receptive anal and insertive vaginal sex in the past 3 months. Vaginal sex was reported by 37% of participants, and exclusive MSM status was associated with higher HIV rates. Condom use was infrequent, with approximately one-third reporting 100% condom use during anal sex. HIV incidence was 10.9 per 100 person-years (95% CI 7.4 to 15.6). Predictors of HIV risk included history of urethral discharge (aHR 0.29, 95% CI 0.08 to 0.98, p=0.046), condom use during receptive anal sex (aHR 0.05, 95% CI 0.01 to 0.41, p=0.006) and frequency of sex with male partners (aHR 1.33/sex act, 95% CI 1.01 to 1.75, p=0.04).

CONCLUSIONS

HIV prevalence and incidence were extremely high in Nairobi MSM SW; a combination of interventions including increasing condom use, pre-exposure prophylaxis and access to effective treatment is urgently needed to decrease HIV transmission in this key population.

Men who have sex with men sensitivity training reduces homoprejudice and increases knowledge among Kenyan healthcare providers in coastal Kenya

INTRODUCTION

Healthcare workers (HCWs) in Africa typically receive little or no training in the healthcare needs of men who have sex with men (MSM), limiting the effectiveness and reach of population-based HIV control measures among this group. We assessed the effect of a web-based, self-directed sensitivity training on MSM for HCWs (www.marps-africa.org), combined with facilitated group discussions on knowledge and homophobic attitudes among HCWs in four districts of coastal Kenya.

METHODS

We trained four district "AIDS coordinators" to provide a two-day training to local HCWs working at antiretroviral therapy-providing facilities in coastal Kenya. Self-directed learning supported by group discussions focused on MSM sexual risk practices, HIV prevention and healthcare needs. Knowledge was assessed prior to training, immediately after training and three months after training. The Homophobia Scale assessed homophobic attitudes and was measured before and three months after training.

RESULTS

Seventy-four HCWs (68% female; 74% clinical officers or nurses; 84% working in government facilities) from 49 health facilities were trained, of whom 71 (96%) completed all measures. At baseline, few HCWs reported any prior training on MSM anal sexual practices, and most HCWs had limited knowledge of MSM sexual health needs. Homophobic attitudes were most pronounced among HCWs who were male, under 30 years of age, and working in clinical roles or government facilities. Three months after training, more HCWs had adequate knowledge compared to baseline (49% vs. 13%, McNemar's test p<0.001); this was most pronounced in those with clinical or administrative roles and in those from governmental health providers. Compared to baseline, homophobic attitudes had decreased significantly three months after training, particularly among HCWs with high homophobia scores at baseline, and there was some evidence of correlation between improvements in knowledge and reduction in homophobic sentiment.

CONCLUSIONS

Scaling up MSM sensitivity training for African HCWs is likely to be a timely, effective and practical means to improve relevant sexual health knowledge and reduce personal homophobic sentiment among HCWs involved in HIV prevention, testing and care in sub-Saharan Africa.

Estimates of the size of key populations at risk for HIV infection: men who have sex with men, female sex workers and injecting drug users in Nairobi, Kenya

OBJECTIVES

Size estimates of populations at higher risk for HIV infection are needed to help policy makers understand the scope of the epidemic and allocate appropriate resources. Population size estimates of men who have sex with men (MSM), female sex workers(FSW) and intravenous drug users (IDU) are few or non-existent in Nairobi, Kenya.

METHODS

We integrated three population size estimation methods into a behavioural surveillance survey among MSM, FSW and IDU in Nairobi during 2010–2011. These methods included the multiplier method, ‘Wisdom of the Crowds’ and an approach that drew on published literature. The median of the three estimates was hypothesised to be the most plausible size estimate with the other results forming the upper and lower plausible bounds. Data were shared with community representatives and stakeholders to finalise ‘best’ point estimates and plausible bounds based on the data collected in Nairobi, a priori expectations from the global literature and stakeholder input.

RESULTS

We estimate there are approximately 11 042 MSM with a plausible range of 10 000–22 222, 29 494 FSW with a plausible range of 10 000–54 467 FSW and approximately 6107 IDU and plausibly 5031–10 937 IDU living in Nairobi.

CONCLUSIONS

We employed multiple methods and used a wide range of data sources to estimate the size of three hidden populations in Nairobi, Kenya. These estimates may be useful to advocate for and to plan, implement and evaluate HIV prevention and care programmes for MSM, FSW and IDU. Surveillance activities should consider integrating population size estimation in their protocols.

Enumeration of sex workers in the central business district of Nairobi, Kenya

Accurate program planning for populations most at risk for HIV/STI acquisition requires knowledge of the size and location where these populations can best be reached. To obtain this information for sex workers operating at 137 hotspots in the central business district (CBD) in Nairobi, Kenya, we utilized a combined mapping and capture-recapture enumeration exercise. The majority of identified hotspots in this study were bars. Based on this exercise, we estimate that 6,904 male and female sex workers (95% confidence intervals, 6690 and 7118) were working nightly in the Nairobi CBD in April 2009. Wide ranges of captures per spot were obtained, suggesting that relatively few hot spots (18%) contain a relatively high proportion of the area's sex workers (65%). We provide geographic data including relatively short distances from hotspots to our dedicated sex worker outreach program in the CBD (mean<1 km), and clustering of hotspots within a relatively small area. Given the size covered and areas where sex work is likely taking place in Nairobi, the estimate is several times lower than what would be obtained if the entire metropolitan area was enumerated. These results have important practical and policy implications for enhancing HIV/STI prevention efforts.