Using Peer-Referral Chains with Incentives to Promote HIV Testing and Identify Undiagnosed HIV Infections Among Crack Users in San Salvador

Impact of Peer Referral on Pre-Exposure Prophylaxis Adherence and Persistence Among Men Who Have Sex with Men: A Cohort Study in China

Peer referral leverages social networks to connect individuals with health services, potentially enhancing pre-exposure prophylaxis (PrEP) use. This study aims to investigate the impact of peer referral on PrEP adherence and persistence among men who have sex with men (MSM) in China. This study is nested in a 12-month PrEP (FTC/TDF) demonstration trial in China from September 2021 to December 2023. Peer referral was defined as participants being referred by peers already enrolled in the trial. PrEP adherence was measured as taking four or more pills per week for daily users or following the 2 + 1 + 1 event-driven regimen at least 75% of the time. PrEP persistence was defined as the time from initiation to discontinuation. We collected data from the first 6 months of follow-up and used generalized estimating equations and Cox regression models to evaluate the association between peer referral and PrEP adherence and persistence. A total of 1,131 MSM initiated PrEP, with 121 (10.7%) referred by peers. At month 6, adherence rates were 75.0% for peer-referred MSM and 67.1% for non-peer-referred MSM. Peer-referred MSM had higher adherence than non-peer-referred MSM (aRR = 1.11, 95% CI: 1.01-1.22). Regarding persistence, 812 (71.8%) MSM continued using PrEP at 6 months of follow-up, and peer-referred MSM were more likely to persist with PrEP (aHR = 1.85, 95% CI: 1.17-2.91). These findings demonstrate the potential of peer referral in promoting PrEP use among MSM, suggesting the value of powerful peer-based interventions like peer navigation in future PrEP outreach.

Respondent-driven sampling is more efficient than facility-based strategies at identifying undiagnosed people who inject drugs living with HIV in India

INTRODUCTION

Injection drug use drives HIV epidemics in many low-resource settings, yet many people who inject drugs (PWID) living with HIV are not diagnosed. We assessed the ability of respondent-driven sampling (RDS) - which uses peer network connections - to identify undiagnosed PWID living with HIV compared to a facility-based strategy in India.

METHODS

In six Indian cities from 2014 to 2017, integrated care centers (ICCs) provided HIV testing. From 2016 to 2017, RDS samples of PWID in these same cities were conducted. Using biometric matching, characteristics associated with identification by RDS only and both RDS and ICC, compared to ICC only were explored. Undiagnosed individuals tested positive and did not report a prior diagnosis. The number needed to recruit (NNR) (average number recruited to find one undiagnosed PWID living with HIV) and the identification rate (average number undiagnosed PWID identified per week) assessed the efficiency of RDS vs. ICCs.

RESULTS

There were 10,759 ICC clients and 6012 RDS participants; 40% of RDS participants were also ICC clients resulting in 14,397 unduplicated PWID. PWID identified by RDS vs. ICC only were more likely to be male (adjusted odds ratios [aOR] RDS only: 6.8, both: 2.7) and living with HIV but undiagnosed (aOR RDS only: 2.5, both: 1.5). Overall, the RDS NNR was 11 and the ICC NNR was 26. The RDS identification rate (18.6/week) was faster than the ICC identification rate (2.7/week) overall and in all cities.

CONCLUSIONS

RDS required screening fewer PWID and more rapidly identified undiagnosed PWID living with HIV as compared to ICCs.

Applying Behavioural Insights to HIV Prevention and Management: a Scoping Review

PURPOSE OF REVIEW

This scoping review summarises the literature on HIV prevention and management interventions utilizing behavioural economic principles encapsulated in the MINDSPACE framework.

RECENT FINDINGS

MINDSPACE is an acronym developed by the UK's behavioural insights team to summarise nine key influences on human behaviour: Messenger, Incentives, Norms, Default, Salience, Priming, Affect, Commitment, and Ego. These effects have been used in various settings to design interventions that encourage positive behaviours. Currently, over 200 institutionalised behavioural insight teams exist internationally, which may draw upon the MINDSPACE framework to inform policy and improve public services. To date, it is not clear how behavioural insights have been applied to HIV prevention and management interventions. After screening 899 studies for eligibility, 124 were included in the final review. We identified examples of interventions that utilised all the MINDSPACE effects in a variety of settings and among various populations. Studies from high-income countries were most common (n = 54) and incentives were the most frequently applied effect (n = 100). The MINDSPACE framework is a useful tool to consider how behavioural science principles can be applied in future HIV prevention and management interventions. Creating nudges to enhance the design of HIV prevention and management interventions can help people make better choices as we strive to end the HIV/AIDS pandemic by 2030.

HIV and Substance Use in Latin America: A Scoping Review

This scoping review aims to explore the interplay between substance use (SU) and HIV in Latin America (LA). Database searches yielded 3481 references; 196 were included. HIV prevalence among people who used substances (PWUS) ranged from 2.8-15.2%. SU definitions were variable throughout studies, and thus data were not easily comparable. In 2019, only 2% of new HIV infections were attributed to injection drug use (IDU) in LA. Factors associated with HIV among PWUS included being female, IDU and homelessness, and PWUS were likely to engage in risky sexual behaviors, start antiretroviral treatment late, have poor adherence, have treatment failure, be lost to follow-up, have comorbidities, and experience higher mortality rates and lower quality of life, as has been reported in PLWH with SU in other regions. Five intervention studies were identified, and only one was effective at reducing HIV incidence in PWUS. Interventions in other regions have varying success depending on context-specific characteristics, highlighting the need to conduct more research in the LA region. Though progress has been made in establishing SU as a major concern in people living with HIV (PLWH), much more is yet to be done to reduce the burden of HIV and SU in LA.

Cumulative Effects of Adding a Small Group Intervention to Social Network Testing on HIV Testing Rates Among Crack Users in San Salvador, El Salvador

The present study evaluates a combination prevention intervention for crack users in San Salvador, El Salvador that included social network HIV testing, community events and small group interventions. We examined the cumulative effects of the social network HIV testing and small group interventions on rates of HIV testing, beyond the increase that we saw with the introduction of the social network HIV testing intervention alone. HIV test data was converted into the number of daily tests and analyzed the immediate and overtime impact of small group interventions during and in the twelve weeks after the small group intervention. The addition of the small group interventions to the baseline of monthly HIV tests resulted in increased rates of testing lasting 7 days after the small group interventions suggesting a reinforcing effect of small group interventions on testing rates.

Chain Peer Referral Approach for HIV Testing Among Adolescents in Kisumu County, Kenya

New HIV infections among adolescents continues to be a large public health burden in sub-Saharan Africa, with few adolescents accessing HIV testing and counseling (HTC) services. We evaluated the effect of a peer referral program among adolescents in Kisumu county, Kenya in accessing HTC. Female adolescents aged 15 to 19 years were recruited from three health clinics in Kisumu County. They, in turn, recruited their peers for HTC by handing out referral cards. Referrals would then recruit their peers and this peer-referral repeated for approximately 5 months. The 252 female index seeds showed a relatively higher-risk profile for HIV compared to the 792 referral participants. The referral system yielded an increased proportion of first-time adolescent testers from 13.1% among index seeds to 42.7% among the second wave of referrals. However, the peer referral system ultimately did not increase the absolute number of adolescents Queryaccessing HTC. Future strategies should consider these findings to better target those with undiagnosed HIV infection.

Intervention Reach and Sexual Risk Reduction of a Multi-level, Community-Based HIV Prevention Intervention for Crack Users in San Salvador, El Salvador

This article examines the effects of a multi-level, community-based HIV prevention intervention for crack users residing in low-income neighborhoods in San Salvador, El Salvador conducted between August 2011 and June 2016. The intervention consisted of three components introduced sequentially: (1) rapid HIV testing in community settings; (2) a social network HIV testing intervention; and (3) small group interventions with crack users who were members of the same social network. The intervention was evaluated with an interrupted time series design in which we used respondent-driven sampling to conduct 7 cross-sectional surveys with crack users along a 3-4 month period for each assessment (total n = 1597). Results revealed a significant increase in exposure to the intervention over time with 50% of the participants reporting exposure to one or more of the three components. Getting an HIV test at the community site was associated with reductions in total times each individual had sex without a condom (p < 0.05) compared to those who had been exposed to no intervention components. Being referred by another crack user through the Social Network HIV intervention was also associated with reductions in total numbers of condomless sex (p < 0.05) The cumulative effect of being exposed to more than one intervention component was associated with reductions in total number of times individuals had condomless sex (p < 0.05). In spite of the high level of intervention reach and that self-reported exposure to intervention components was associated with lower sexual risk, reductions in sexual risk over time were not observed in the full sample, indicating that the penetration of HIV prevention components was not sufficient to produce population level change.