A Novel HIV-1 RNA Testing Intervention to Detect Acute and Prevalent HIV Infection in Young Adults and Reduce HIV Transmission in Kenya: Protocol for a Randomized Controlled Trial

Temporal trends and transmission dynamics of pre-treatment HIV-1 drug resistance within and between risk groups in Kenya, 1986-2020

BACKGROUND

Evidence on the distribution of pre-treatment HIV-1 drug resistance (HIVDR) among risk groups is limited in Africa. We assessed the prevalence, trends and transmission dynamics of pre-treatment HIVDR within and between MSM, people who inject drugs (PWID), female sex workers (FSWs), heterosexuals (HETs) and perinatally infected children in Kenya.

METHODS

HIV-1 partial pol sequences from antiretroviral-naive individuals collected from multiple sources between 1986 and 2020 were used. Pre-treatment reverse transcriptase inhibitor (RTI), PI and integrase inhibitor (INSTI) mutations were assessed using the Stanford HIVDR database. Phylogenetic methods were used to determine and date transmission clusters.

RESULTS

Of 3567 sequences analysed, 550 (15.4%, 95% CI: 14.2-16.6) had at least one pre-treatment HIVDR mutation, which was most prevalent amongst children (41.3%), followed by PWID (31.0%), MSM (19.9%), FSWs (15.1%) and HETs (13.9%). Overall, pre-treatment HIVDR increased consistently, from 6.9% (before 2005) to 24.2% (2016-20). Among HETs, pre-treatment HIVDR increased from 6.6% (before 2005) to 20.2% (2011-15), but dropped to 6.5% (2016-20). Additionally, 32 clusters with shared pre-treatment HIVDR mutations were identified. The majority of clusters had R0 ≥ 1.0, indicating ongoing transmissions. The largest was a K103N cluster involving 16 MSM sequences sampled between 2010 and 2017, with an estimated time to the most recent common ancestor (tMRCA) of 2005 [95% higher posterior density (HPD), 2000-08], indicating propagation over 12 years.

CONCLUSIONS

Compared to HETs, children and key populations had higher levels of pre-treatment HIVDR. Introduction of INSTIs after 2017 may have abrogated the increase in pre-treatment RTI mutations, albeit in the HET population only. Taken together, our findings underscore the need for targeted efforts towards equitable access to ART for children and key populations in Kenya.

Modeling the impact of different PrEP targeting strategies combined with a clinic-based HIV-1 nucleic acid testing intervention in Kenya

BACKGROUND

Up to 69% of adults who acquire HIV in Kenya seek care for acute retroviral symptoms, providing an important opportunity for early diagnosis and HIV care engagement. The Tambua Mapema Plus (TMP) trial tested a combined HIV-1 nucleic acid testing, linkage, treatment, and partner notification intervention for adults with symptoms of acute HIV infection presenting to health facilities in coastal Kenya. We estimated the potential impact on the Kenyan HIV epidemic of providing PrEP to individuals testing negative in TMP, if scaled up.

METHODS

We developed an agent-based simulation of HIV-1 transmission using TMP data and current Kenyan statistics. PrEP interventions were layered onto a model of TMP as standard of care, to estimate additional potential population-level impact of enrolling HIV-negative individuals identified through TMP on PrEP over 10 years. Four scenarios were modeled: PrEP for uninfected individuals in disclosed serodiscordant couples; PrEP for individuals with concurrent partnerships; PrEP for all uninfected individuals identified through TMP; and PrEP integrated into the enhanced partner services component of TMP.

FINDINGS

Providing PrEP to both individuals with concurrent partnerships and uninfected partners identified through enhanced partner services reduced new HIV infections and was efficient based on numbers needed to treat (NNT). The mean percent of infections averted was 2.79 (95%SI:-10.83, 15.24) and 4.62 (95%SI:-9.5, 16.82) when PrEP uptake was 50% and 100%, respectively, and median NNT was 22.54 (95%SI:not defined, 6.45) and 27.55 (95%SI:not defined, 11.0), respectively. Providing PrEP for all uninfected individuals identified through TMP averted up to 12.68% (95%SI:0.17, 25.19) of new infections but was not efficient based on the NNT: 200.24 (95%SI:523.81, 123.23).

CONCLUSIONS

Providing PrEP to individuals testing negative for HIV-1 nucleic acid after presenting to a health facility with symptoms compatible with acute HIV adds value to the TMP intervention, provided PrEP is targeted effectively and efficiently.

FUNDING

National Institutes of Health, Sub-Saharan African Network for TB/HIV Research Excellence.

Testing strategies to detect acute and prevalent HIV infection in adult outpatients seeking healthcare for symptoms compatible with acute HIV infection in Kenya: a cost-effectiveness analysis

BACKGROUND

Detection of acute and prevalent HIV infection using point-of-care nucleic acid amplification testing (POC-NAAT) among outpatients with symptoms compatible with acute HIV is critical to HIV prevention, but it is not clear if it is cost-effective compared with existing HIV testing strategies.

METHODS

We developed and parametrised a decision tree to compare the cost-effectiveness of (1) provider-initiated testing and counselling (PITC) using rapid tests, the standard of care; (2) scaled-up provider-initiated testing and counselling (SU-PITC) in which all patients were tested with rapid tests unless they opted out; and (3) opt-out testing and counselling using POC-NAAT, which detects both acute and prevalent infection. The model-based analysis used data from the Tambua Mapema Plus randomised controlled trial of a POC-NAAT intervention in Kenya, supplemented with results from a stochastic, agent-based network model of HIV-1 transmission and data from published literature. The analysis was conducted from the perspective of the Kenyan government using a primary outcome of cost per disability-adjusted life-year (DALY) averted over a 10-year time horizon.

RESULTS

After analysing the decision-analytical model, the average per patient cost of POC-NAAT was $214.9 compared with $173.6 for SU-PITC and $47.3 for PITC. The mean DALYs accumulated per patient for POC-NAAT were 0.160 compared with 0.176 for SU-PITC and 0.214 for PITC. In the incremental analysis, SU-PITC was eliminated due to extended dominance, and the incremental cost-effectiveness ratio (ICER) comparing POC-NAAT to PITC was $3098 per DALY averted. The ICER was sensitive to disability weights for HIV/AIDS and the costs of antiretroviral therapy.

CONCLUSION

POC-NAAT offered to adult outpatients in Kenya who present for care with symptoms compatible with AHI is cost-effective and should be considered for inclusion as the standard of HIV testing in this population.

TRIAL REGISTRATION NUMBER

Tambua Mapema ("Discover Early") Plus study (NCT03508908) conducted in Kenya (2017-2020) i.e., Post-results.

Modeling the Impact of HIV-1 Nucleic Acid Testing Among Symptomatic Adult Outpatients in Kenya

BACKGROUND

Up to 69% of adults who acquire HIV in Kenya seek care before seroconversion, providing an important opportunity for early diagnosis and treatment. The Tambua Mapema Plus (TMP) trial tested a combined HIV-1 nucleic acid testing, linkage, treatment, and partner notification intervention for adults aged 18-39 years with symptoms of acute HIV infection presenting to health facilities in coastal Kenya. We estimated the potential impact of TMP on the Kenyan HIV epidemic.

METHODS

We developed an agent-based network model of HIV-1 transmission using TMP data and Kenyan statistics to estimate potential population-level impact of targeted facility-based testing over 10 years. Three scenarios were modeled: standard care [current use of provider-initiated testing and counseling (PITC)], standard HIV rapid testing scaled to higher coverage obtained in TMP (scaled-up PITC), and the TMP intervention.

RESULTS

Standard care resulted in 90.7% of persons living with HIV (PLWH) knowing their status, with 67.5% of those diagnosed on treatment. Scaled-up PITC resulted in 94.4% of PLWH knowing their status and 70.4% of those diagnosed on treatment. The TMP intervention achieved 97.5% of PLWH knowing their status and 80.6% of those diagnosed on treatment. The percentage of infections averted was 1.0% (95% simulation intervals: -19.2% to 19.9%) for scaled-up PITC and 9.4% (95% simulation intervals: -8.1% to 24.5%) for TMP.

CONCLUSION

Our study suggests that leveraging new technologies to identify acute HIV infection among symptomatic outpatients is superior to scaled-up PITC in this population, resulting in >95% knowledge of HIV status, and would reduce new HIV infections in Kenya.

Predictors of testing history and new HIV diagnosis among adult outpatients seeking care for symptoms of acute HIV infection in coastal Kenya: a cross-sectional analysis of intervention participants in a stepped-wedge HIV testing trial

Background

HIV testing is the first step to stop transmission. We aimed to evaluate HIV testing history and new diagnoses among adult outpatients in Kenya aged 18–39 years seeking care for symptoms of acute HIV infection (AHI).

Methods

The Tambua Mapema Plus study, a stepped-wedge trial, enrolled patients presenting to care at six primary care facilities with symptoms of AHI for a targeted HIV-1 nucleic acid (NA) testing intervention compared with standard provider-initiated testing using rapid antibody tests. Intervention participants underwent a questionnaire and NA testing, followed by rapid tests if NA-positive. Multinomial logistic regression was used to analyse factors associated with never testing or testing > 1 year ago (“late retesting”) relative to testing ≤ 1 year ago (“on-time testers”). Logistic regression was used to analyse factors associated with new diagnosis. All analyses were stratified by sex.

Results

Of 1,500 intervention participants, 613 (40.9%) were men. Overall, 250 (40.8%) men vs. 364 (41.0%) women were late retesters, and 103 (16.8%) men vs. 50 (5.6%) women had never tested prior to enrolment. Younger age, single status, lower education level, no formal employment, childlessness, sexual activity in the past 6 weeks, and > 1 sexual partner were associated with testing history among both men and women. Intimate partner violence > 1 month ago, a regular sexual partner, and concurrency were associated with testing history among women only. New diagnoses were made in 37 (2.5%) participants (17 men and 20 women), of whom 8 (21.6%) had never tested and 16 (43.2%) were late retesters. Newly-diagnosed men were more likely to have symptoms for > 14 days, lower education level and no religious affiliation and less likely to be young, single, and childless than HIV-negative men; newly-diagnosed women were more likely to report fever than HIV-negative women. Among men, never testing was associated with fivefold increased odds (95% confidence interval 1.4–20.9) of new diagnosis relative to on-time testers in adjusted analyses.

Conclusion

Most new HIV diagnoses were among participants who had never tested or tested > 1 year ago. Strengthening provider-initiated testing targeting never testers and late retesters could decrease time to diagnosis among symptomatic adults in coastal Kenya.

Trial registration

ClinicalTrials.gov Identifier: NCT03508908 registered on 26/04/2018.

“Facilitating HIV status adjustment: Qualitative insights from the Tambua Mapema proof-of-concept study in Kenya”

Systematic efforts are needed to prepare persons newly diagnosed with acute or chronic HIV infection to cope. We examined how patients dealt with this news, looking at how readiness to accept an HIV diagnosis impacted treatment outcomes, prevention of transmission, and HIV status disclosure. We examined vulnerability and agency over time and considered implications for policy and practice. A qualitative sub-study was embedded in the Tambua Mapema (“Discover Early”) Plus (TMP) study (NCT03508908), conducted in coastal Kenya between 2017 and 2020, which was a stepped wedge trial to evaluate an opt-out HIV-1 nucleic acid testing intervention diagnosing acute and chronic HIV infections. Diagnosed participants were offered antiretroviral therapy (ART), viral load monitoring, HIV partner notification services, and provision of pre-exposure prophylaxis (PrEP) to their uninfected partners. Data were analyzed using thematic approaches. Participants included 24 individuals who completed interviews at four time points (2 weeks and 3, 6, and 9 months after diagnosis), including 18 patients (11 women and 7 men) and 6 partners (1 woman, 5 men, of whom 4 men started PrEP). Acceptance of HIV status was often a long, individualized, and complex process, whereby participants’ coping strategies affected day-to-day issues and health over time. Relationship status strongly impacted coping. In some instances, couples supported each other, but in others, couples separated. Four main themes impacted participants’ sense of agency: acceptance of diagnosis and commitment to ART; positive feedback after attaining viral load suppression; recognition of partner supportive role and focus on sustained healthcare support whereby religious meaning was often key to successful transition. To support patients with acute or newly diagnosed chronic HIV, healthcare and social systems must be more responsive to the needs of the individual, while also improving quality of care, strengthening continuity of care across facilities, and promoting community support.

Effect of an opt-out point-of-care HIV-1 nucleic acid testing intervention to detect acute and prevalent HIV infection in symptomatic adult outpatients and reduce HIV transmission in Kenya: a randomized controlled trial

BACKGROUND

In sub-Saharan Africa, adult outpatients with symptoms of acute infectious illness are not routinely tested for prevalent or acute HIV infection (AHI) when seeking healthcare.

METHODS

Adult symptomatic outpatients aged 18-39 years were evaluated by a consensus AHI risk score. Patients with a risk score ≥ 2 and no previous HIV diagnosis were enrolled in a stepped-wedge trial of opt-out delivery of point-of-care (POC) HIV-1 nucleic acid testing (NAAT), compared with standard provider-initiated HIV testing using rapid tests in the observation period. The primary outcome was the number of new diagnoses in each study period. Generalized estimating equations with a log-binomial link and robust variance estimates were used to account for clustering by health facility. The trial is registered with ClinicalTrials.gov NCT03508908.

RESULTS

Between 2017 and 2020, 13 (0.9%) out of 1374 participants in the observation period and 37 (2.5%) out of 1500 participants in the intervention period were diagnosed with HIV infection. Of the 37 newly diagnosed cases in the intervention period, two (5.4%) had AHI. Participants in the opt-out intervention had a two-fold greater odds of being diagnosed with HIV (odds ratio = 2.2, 95% confidence interval: 1.39-3.51) after adjustment for factors imbalanced across study periods.

CONCLUSIONS

Among symptomatic adults aged 18-39 years targeted by our POC NAAT intervention, we identified one chronic HIV infection for every 40 patients and one AHI patient for every 750 patients tested. Although AHI yield was low in this population, routinely offered opt-out testing could diagnose twice as many patients as an approach relying on provider discretion.

HIV testing approaches to reach the first UNAIDS 95% target in sub-Saharan Africa

HIV testing is a crucial first step to accessing HIV prevention and treatment services and to achieving the UNAIDS target of 95% of people living with HIV being aware of their status by 2030. Combined implementation of facility-based and community-based approaches has helped to achieve high levels of HIV testing coverage in many countries including those in sub-Saharan Africa. Approaches such as index testing and self-testing help to reach individuals at higher risk of acquiring HIV, men, and those less likely to use health facilities or community-based services. However, as the proportion of people living with HIV who are aware of their HIV status has risen, the challenge of reaching those who remain undiagnosed or those who are at high risk of acquiring HIV has grown. Demand generation and novel testing approaches will be necessary to reach undiagnosed people living with HIV and to promote frequent retesting among key and priority populations.

High patient acceptability but low coverage of provider-initiated HIV testing among adult outpatients with symptoms of acute infectious illness in coastal Kenya

Background

Only approximately one in five adults are offered HIV testing by providers when seeking care for symptoms of acute illness in Sub-Saharan Africa. Our aims were to estimate testing coverage and identify predictors of provider-initiated testing and counselling (PITC) and barriers to PITC implementation in this population.

Methods

We assessed HIV testing coverage among adult outpatients 18–39 years of age at four public and two private health facilities in coastal Kenya, during a 3- to 6-month surveillance period at each facility. A subset of patients who reported symptoms including fever, diarrhoea, fatigue, body aches, sore throat or genital ulcers were enrolled to complete a questionnaire independently of PITC offer. We assessed predictors of PITC in this population using generalised estimating equations and identified barriers to offering PITC through focus group discussion with healthcare workers (HCW) at each facility.

Results

Overall PITC coverage was 13.7% (1600 of 11,637 adults tested), with 1.9% (30) testing positive. Among 1,374 participants enrolled due to symptoms, 378 (27.5%) were offered PITC and 352 (25.6%) were tested, of whom 3.7% (13) tested positive. Among participants offered HIV testing, 93.1% accepted it; among participants not offered testing, 92.8% would have taken an HIV test if offered. The odds of completed PITC were increased among older participants (adjusted odds ratio [aOR] 1.7, 95% confidence interval [CI] 1.4–2.1 for 30–39 years, relative to 18–24 years), men (aOR 1.3, 95% CI 1.1–1.7); casual labourers (aOR 1.3, 95% CI 1.0–1.7); those paying by cash (aOR 1.2, 95% CI 1.0–1.4) or insurance (aOR 3.0, 95% CI 1.5–5.8); participants with fever (aOR 1.5, 95% CI 1.2–1.8) or genital ulcers (aOR 4.0, 95% CI 2.7–6.0); and who had tested for HIV >1 year ago (aOR 1.4, 95% CI 1.0–2.0) or had never tested (aOR 2.2, 95% CI 1.5–3.1). Provider barriers to PITC implementation included lack of HCW knowledge and confidence implementing guidelines, limited capacity and health systems constraints.

Conclusion

PITC coverage was low, though most patients would accept testing if offered. Missed opportunities to promote testing during care-seeking were common and innovative solutions are needed.