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.

Virologic Nonsuppression and HIV Drug Resistance Among People Who Inject Drugs and Their Sexual and Injecting Partners in Kenya.

We evaluated the prevalence and correlates of HIV viral nonsuppression and HIV drug resistance (HIV-DR) in a cohort of people who inject drugs living with HIV (PWID-LH) and their sexual and injecting partners living with HIV in Kenya. HIV-DR testing was performed on participants with viral nonsuppression. Of 859 PWID-LH and their partners, 623 (72.5%) were on antiretroviral therapy (ART) ≥4 months and 148/623 (23.8%) were not virally suppressed. Viral nonsuppression was more common among younger participants and those on ART for a shorter duration. Among 122/148 (82.4%) successfully sequenced samples, 55 (45.1%) had detectable major HIV-DR mutations, mainly to non-nucleoside and nucleotide reverse transcriptase inhibitors (NNRTI and NRTI). High levels of HIV-DR among those with viral nonsuppression suggests need for viral load monitoring, adherence counseling, and timely switching to alternate ART regimens in this key population.

Prevalence and correlates of violence among sexual and injecting partners of people who inject drugs living with HIV in Kenya: a cross-sectional study.

BACKGROUND: In Kenya, violence is common among people who inject drugs (PWID) living with HIV and their sexual and injecting partners and may lead to decreased uptake of HIV services, increased HIV risk behaviors, and increased HIV transmission. Violence is defined as any physical harm, threatened harm, or forced sexual acts inflicted on a person in the past year. Understanding the nature of violence and its correlates among PWID and their partners will inform population-specific public health interventions and policy recommendations. METHODS: This is a cross-sectional study nested in a prospective cohort study conducted in eight public health centers, methadone clinics, and needle syringe programs in Nairobi, Kilifi, and Mombasa counties in Kenya. 3,302 sexual and/or injecting partners of PWID living with HIV were recruited through assisted partner services and participated in the study. Prevalence and correlates of violence were identified using the Wald test and negative binomial regression. RESULTS: Out of 3302 study participants, 1439 (44%) had experienced violence within the past year. Physical violence was the most common form of violence experienced (35%), followed by being threatened (23%) or subjected to sexual violence (7%). In an adjusted analysis, female participants reported higher experiences of sexual violence (prevalence ratio [PR] = 2.46; 95% confidence interval [CI] 1.62, 3.74; p < 0.001) compared to male participants. In adjusted analysis, coastal residents had a higher experience of overall violence (PR = 1.48; 95% CI 1.27, 1.72; p < 0.001) than those living in Nairobi. This regional effect was relatively stronger among the female respondents (pinteraction = 0.025). Participants' sex modified the association between region and experiencing violence after adjusting potential confounding factors. CONCLUSIONS: The study reveals the prevalence of violence among PWID and identifies high-risk sub-groups, including women, specifically for sexual violence, and coastal residents. Tailored interventions addressing their unique needs are essential. A holistic approach that combines violence prevention and response, comprehensive harm reduction, healthcare access, and community support is crucial to address the complex issue of drug use and HIV burden among PWID in Kenya for improved health outcomes.

SARS-CoV-2 antibody prevalence, correlates, and access to harm reduction services among people who inject drugs living with and without HIV and their partners in Kenya.

BACKGROUND: In sub-Saharan Africa many people who inject drugs (PWID) are living with undiagnosed or untreated HIV and experience high levels of poverty and conditions that can contribute to worse outcomes from SARS-CoV-2 infection. Identifying the burden of SARS-CoV-2 infection in marginalized populations like PWID may contribute to controlling the pandemic. METHODS: This is a nested cross-sectional study within an ongoing cohort study that recruits PWID living with HIV and their injecting and/or sexual partners at needle and syringe program sites and methadone clinics in Kenya. Blood samples were collected from consenting participants at enrollment to determine SARS-CoV-2 antibodies using a Platellia BioRad SARS-CoV-2 total antibody enzyme-linked immunosorbent assay. Baseline data were collected on HIV status, antiretroviral therapy and methadone adherence. We used logistic regression to identify factors associated with antibody positivity and descriptive statistics to report SARS-CoV-2 antibody prevalence. RESULTS: One thousand participants were enrolled between April and July 2021, of whom 323 (32.3%) were women and 677 (67.7%) were men. Median age of participants was 36 years (interquartile range: 30, 42). SARS-CoV-2 antibody positivity was found in 309 (30.9%) participants. Disruption in obtaining methadone service was reported by 106 (24.3%) of the participants. Men were significantly less likely than women to have SARS-CoV-2 antibodies (adjusted odds ratio [aOR] = 0.68, 95% confidence interval [CI] 0.51, 0.95; p < 0.01) Participants who reported a sexual or injecting partner diagnosed with SARS-CoV-2 were twofold more likely to have SARS-CoV-2 antibodies detected (aOR = 2.21, 95% CI 1.06, 4.58; p < 0.032). Living with HIV was not associated with presence of SARS-CoV-2 antibodies. CONCLUSION: The seroprevalence of SARS-CoV-2 of 30.9% in this cohort suggests high transmission rates within this population. SARS-CoV-2 seroprevalence was similar for people living with and without HIV. A large portion of this population was noted to have had disruption in access to harm reduction services.

Accounting for population structure in genetic studies of cystic fibrosis.

CFTR F508del (c.1521_1523delCTT, p.Phe508delPhe) is the most common pathogenic allele underlying cystic fibrosis (CF), and its frequency varies in a geographic cline across Europe. We hypothesized that genetic variation associated with this cline is overrepresented in a large cohort (N > 5,000) of persons with CF who underwent whole-genome sequencing and that this pattern could result in spurious associations between variants correlated with both the F508del genotype and CF-related outcomes. Using principal-component (PC) analyses, we showed that variation in the CFTR region disproportionately contributes to a PC explaining a relatively high proportion of genetic variance. Variation near CFTR was correlated with population structure among persons with CF, and this correlation was driven by a subset of the sample inferred to have European ancestry. We performed genome-wide association studies comparing persons with CF with one versus two copies of the F508del allele; this allowed us to identify genetic variation associated with the F508del allele and to determine that standard PC-adjustment strategies eliminated the significant association signals. Our results suggest that PC adjustment can adequately prevent spurious associations between genetic variants and CF-related traits and are therefore effective tools to control for population structure even when population structure is confounded with disease severity and a common pathogenic variant.

Characteristics associated with HIV and hepatitis C seroprevalence among sexual and injecting partners of HIV positive persons who inject drugs in Nairobi and coastal Kenya.

BACKGROUND: Persons who inject drugs (PWID) have higher HIV and hepatitis C virus (HCV) seroprevalence than the general population in many parts of sub-Saharan Africa (SSA). The seroprevalences of HIV and HCV are also higher in coastal Kenya than in Nairobi. Understanding drivers of regional HIV and HCV variation among PWID in Kenya may inform population-specific prevention interventions. METHODS: Using a cross-sectional study, we defined HIV and HCV seroprevalence among persons identified as sexual or injecting partners of HIV positive PWID in two regions of Kenya and used logistic regression to identify demographic and behavioral characteristics associated with higher seroprevalence. RESULTS: Among 2386 partners, 469 (19.7%) tested HIV positive and 297(12.4%) tested HCV antibody positive. Partners on the Coast were more likely to live with HIV (seroprevalences: Coast = 23.8%, Nairobi = 17.1%; p < 0.001) and be HCV antibody positive (seroprevalences: Coast = 17.0%, Nairobi = 8.6%; p < 0.001). After adjusting for sex, age, and years injecting and accounting for clustering by site, the higher prevalence of both diseases in the Coast remained significant for HIV (OR 1.68, 95% CI 1.13-2.51) but not for HCV (OR 1.72, 95% CI 0.84-3.74). Compared to those recruited in Nairobi, partners on the Coast were older (Coast = 35 years, Nairobi = 31 years; p < 0.001), more likely to be male (Coast = 77.6%, Nairobi = 61.7%; p < 0.001), to have paid (Coast = 59.2%, Nairobi = 32.8%; p < 0.001) or received (Coast = 44.2%, Nairobi 35.4%; p < 0.001) money for sex, or to have had sex with someone they knew to be HIV positive (Coast 22.0%, Nairobi 10.8%; p < 0.001). Partners who had injected for five or more years had 1.48 times greater odds (95% CI 1.20-1.82) of living with HIV compared to partners who injected less than 5 years and more than twice the odds of HCV (95% CI 1.84-4.11). CONCLUSION: HIV and HCV seroprevalence among sexual and injecting partners of PWID was, respectively, 5 times and > 12 times greater than is reported among the general population in Kenya (4% and < 1%, respectively). Providing resources and education will be crucial to reduce exposure and to maintain the lower needle and equipment sharing that we observed compared to other studies.

A new implementation of a semi-continuous method for DNA mixture interpretation.

A new calculation module within the PopStats module of the CODIS software package, based on the underlying mathematics presented in the MixKin software package, has been developed for assigning the Likelihood Ratio (LR) of DNA mixture profiles. This module uses a semi-continuous model that allows for population structure and allelic drop-out and drop-in but does not require allelic peak heights or other laboratory-specific parameters. This new implementation (named SC Mixture), like MixKin, does not specify or estimate a probability of drop-out. Instead, each contributor to a mixture has an independent drop-out rate, and the probability of the mixture profile for a specified proposition concerning the contributors is integrated over the range of possible drop-out rates. The allelic drop-in rate and the population structure parameter, theta, used by the software are specified by the user. The user can examine up to five contributors to a mixture, however, conditioning on assumed contributors and limiting the number of unknowns in both numerator and denominator hypotheses greatly improves performance. We report results from an extensive validation study performed for ten mixtures with each of one (single source), two, three, four, or five contributors, with four combinations of drop-in rate and a population structure parameter. Each mixture was run as a complete profile or with the random removal of alleles to simulate drop-out. All 1620 combinations were evaluated with PopStats, MixKin, and LRmix and considerable consistency was found among the results with all three packages.