Last data update: May 06, 2024. (Total: 46732 publications since 2009)
Records 1-6 (of 6 Records) |
Query Trace: Maher AD[original query] |
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Performance of a novel rapid test for recent HIV infection among newly-diagnosed pregnant adolescent girls and young women in four high-HIV-prevalence districts-Malawi, 2017-2018
Agyemang EA , Kim AA , Dobbs T , Zungu I , Payne D , Maher AD , Curran K , Kim E , Kwalira H , Limula H , Adhikari A , Welty S , Kandulu J , Nyirenda R , Auld AF , Rutherford GW , Parekh BS . PLoS One 2022 17 (2) e0262071 Tests for recent HIV infection (TRI) distinguish recent from long-term HIV infections using markers of antibody maturation. The limiting antigen avidity enzyme immunoassay (LAg EIA) is widely used with HIV viral load (VL) in a recent infection testing algorithm (RITA) to improve classification of recent infection status, estimate population-level HIV incidence, and monitor trends in HIV transmission. A novel rapid test for recent HIV infection (RTRI), Asanté™, can determine HIV serostatus and HIV recency within minutes on a lateral flow device through visual assessment of test strip or reader device. We conducted a field-based laboratory evaluation of the RTRI among pregnant adolescent girls and young women (AGYW) attending antenatal clinics (ANC) in Malawi.We enrolled pregnant AGYW aged <25 years testing HIV-positive for the first time at their first ANC visit from 121 ANCs in four high-HIV burden districts. Consenting participants provided blood for recency testing using LAg EIA and RTRI, which were tested in central laboratories. Specimens with LAg EIA normalized optical density values ≤2.0 were classified as probable recent infections. RTRI results were based on: (1) visual assessment: presence of a long-term line (LT) indicating non-recent infection and absence of the line indicating recent infection; or (2) a reader; specimens with LT line intensity units <3.0 were classified as probable recent infections. VL was measured for specimens classified as a probable recent infections by either assay; those with HIV-1 RNA ≥1,000 copies/mL were classified as confirmed recent infections. We evaluated the performance of the RTRI by calculating correlation between RTRI and LAg EIA results, and percent agreement and kappa between RTRI and LAg EIA RITA results.Between November 2017 to June 2018, 380 specimens were available for RTRI evaluation; 376 (98.9%) were confirmed HIV-positive on RTRI. Spearman's rho between RTRI and LAg EIA was 0.72 indicating strong correlation. Percent agreement and kappa between RTRI- and LAg EIA-based RITAs were >90% and >0.65 respectively indicating substantial agreement between the RITAs.This was the first field evaluation of an RTRI in sub-Saharan Africa, which demonstrated good performance of the assay and feasibility of integrating RTRI into routine HIV testing services for real-time surveillance of recent HIV infection. |
Improving the benefits of HIV testing and referrals in large household surveys through active linkages to care: lessons and recommendations from the Namibia population-based HIV impact assessment (NAMPHIA), 2017
Grasso MA , Hamunime N , Maher AD , Cockburn D , Williams DB , Taffa N , Hong SY , Jackson K , Wolkon A , Low A , Stephens SC . AIDS Care 2021 33 (10) 1-4 In household-based surveys that include rapid HIV testing services (HTS), passive referral systems that give HIV-positive participants information about how and where to access ART but minimal follow-up support from survey staff may result in suboptimal linkage. In the 2017 Namibia Population-based HIV Impact Assessment (NAMPHIA), we piloted a system of active linkage to care and ART (ALCART) that utilized the infrastructure of existing community-based partner organizations (CBPOs). All HIV-positive participants age 15-64 years not on ART were given standard passive referrals to ART plus the option to participate in ALCART. Cases were assigned to CBPOs in participants' localities. Healthcare workers from the CBPO's contacted cases and facilitated their linkage to facility-based ART. A total of 510 participants were eligible and consented to ALCART. The majority were new diagnoses (80.8%), while the remainder were previously diagnosed but not on ART (19.2%). Of the 510, 473 (92.7%) were successfully linked into care. Of these, all but one initiated ART. Our ALCART system used existing CBPOs and contributed to >90% linkage-to-care and >99% ART-initiation among linked participants in a large, nationally-representative survey. This approach can be used to improve the potential benefits of HTS in other large population-based surveys. |
HIV prevalence, risk factors for infection, and uptake of prevention, testing, and treatment among female sex workers in Namibia
Jonas A , Patel SV , Katuta F , Maher AD , Banda KM , Gerndt K , Pietersen I , Menezes de Prata N , Mutenda N , Nakanyala T , Kisting E , Kawana B , Nietschke AM , Prybylski D , McFarland W , Lowrance DW . J Epidemiol Glob Health 2020 10 (4) 351-358 BACKGROUND: In most settings, Female Sex Workers (FSW) bear a disproportionate burden of Human Immunodeficiency Virus (HIV) disease worldwide. Representative data to inform the development of behavioral and biomedical interventions for FSW in Namibia have not been published. OBJECTIVES: Our objectives were to measure HIV prevalence, identify risk factors for infection, and describe uptake of prevention, testing, and treatment among FSW in Namibia. METHODS: We conducted cross-sectional surveys using Respondent-driven Sampling (RDS) in the Namibian cities of Katima Mulilo, Oshikango, Swakopmund/Walvis Bay, and Windhoek. Participating FSW completed behavioral questionnaires and rapid HIV testing. RESULTS: City-specific ranges of key indicators were: HIV prevalence (31.0-52.3%), reached by prevention programs in the past 12 months (46.9-73.6%), condom use at last sex with commercial (82.1-91.1%) and non-commercial (87.0-94.2%) partners, and tested for HIV within past 12 months or already aware of HIV-positive serostatus (56.9-82.1%). Factors associated with HIV infection varied by site and included: older age, having multiple commercial or non-commercial sex partners, unemployment, being currently out of school, and lower education level. Among HIV-positive FSW, 57.1% were aware of their HIV-positive serostatus and 33.7% were on antiretroviral treatment. DISCUSSION: Our results indicate extremely high HIV prevalence and low levels of case identification and treatment among FSW in Namibia. Our results, which are the first representative community-based estimates among FSW in Namibia, can inform the scale-up of interventions to reduce the risk for HIV acquisition and onward transmission, including treatment as prevention and pre-exposure prophylaxis. |
Rates and correlates of HIV incidence in Namibia's Zambezi region: Sentinel, community-based cohort study, 2014 to 2016
Maher AD , Nakanyala T , Mutenda N , Banda KM , Prybylski D , Wolkon A , Jonas A , Sawadogo S , Ntema C , Chipadze MR , Sinvula G , Tizora A , Mwandambele A , Chaturvedi S , Agovi AM , Agolory S , Hamunime N , Lowrance DW , McFarland W , Patel SV . JMIR Public Health Surveill 2020 6 (2) e17107 BACKGROUND: Direct measures of HIV incidence are needed to assess the population-level impact of prevention programs but are scarcely available in subnational epidemic hotspots of sub-Saharan Africa. We created a sentinel HIV incidence cohort within a community-based program that provided home-based HIV testing to all residents of Namibia's Zambezi region, where approximately 24% of the adult population was estimated to be living with HIV. OBJECTIVE: The aim of this study was to estimate HIV incidence, detect correlates of HIV acquisition, and assess the feasibility of the sentinel, community-based approach to HIV incidence surveillance in a subnational epidemic hotspot. METHODS: Following the program's initial home-based testing (December 2014-July 2015), we purposefully selected 10 clusters of 60 to 70 households each and invited residents who were HIV negative and aged >/=15 years to participate in the cohort. Consenting participants completed behavioral interviews and a second HIV test approximately 1 year later (March-September 2016). We used Poisson models to calculate HIV incidence rates between baseline and follow-up and multivariable Cox proportional hazard models to assess the correlates of seroconversion. RESULTS: Among 1742 HIV-negative participants, 1624 (93.23%) completed follow-up. We observed 26 seroconversions in 1954 person-years (PY) of follow-up, equating to an overall incidence rate of 1.33 per 100 PY (95% CI 0.91-1.95). Among women, the incidence was 1.55 per 100 PY (95% CI 1.12-2.17) and significantly higher among those aged 15 to 24 years and residing in rural areas (adjusted hazard ratio [aHR] 4.26, 95% CI 1.39-13.13; P=.01), residing in the Ngweze suburb of Katima Mulilo city (aHR 2.34, 95% CI 1.25-4.40; P=.01), who had no prior HIV testing in the year before cohort enrollment (aHR 3.38, 95% CI 1.04-10.95; P=.05), and who had engaged in transactional sex (aHR 17.64, 95% CI 2.88-108.14; P=.02). Among men, HIV incidence was 1.05 per 100 PY (95% CI 0.54-2.31) and significantly higher among those aged 40 to 44 years (aHR 13.04, 95% CI 5.98-28.41; P<.001) and had sought HIV testing outside the study between baseline and follow-up (aHR 8.28, 95% CI 1.39-49.38; P=.02). No seroconversions occurred among persons with HIV-positive partners on antiretroviral treatment. CONCLUSIONS: Nearly three decades into Namibia's generalized HIV epidemic, these are the first estimates of HIV incidence for its highest prevalence region. By creating a sentinel incidence cohort from the infrastructure of an existing community-based testing program, we were able to characterize current transmission patterns, corroborate known risk factors for HIV acquisition, and provide insight into the efficacy of prevention interventions in a subnational epidemic hotspot. This study demonstrates an efficient and scalable framework for longitudinal HIV incidence surveillance that can be implemented in diverse sentinel sites and populations. |
Task-shifting point-of-care CD4+ testing to lay health workers in HIV care and treatment services in Namibia
Kaindjee-Tjituka F , Sawadogo S , Mutandi G , Maher AD , Salomo N , Mbapaha C , Neo M , Beukes A , Gweshe J , Muadinohamba A , Lowrance DW . Afr J Lab Med 2017 6 (1) 643 Introduction: Access to CD4+ testing remains a common barrier to early initiation of antiretroviral therapy among persons living with HIV/AIDS in low- and middle-income countries. The feasibility of task-shifting of point-of-care (POC) CD4+ testing to lay health workers in Namibia has not been evaluated. Methods: From July to August 2011, Pima CD4+ analysers were used to improve access to CD4+ testing at 10 selected public health facilities in Namibia. POC Pima CD4+ testing was performed by nurses or lay health workers. Venous blood samples were collected from 10% of patients and sent to centralised laboratories for CD4+ testing with standard methods. Outcomes for POC Pima CD4+ testing and patient receipt of results were compared between nurses and lay health workers and between the POC method and standard laboratory CD4+ testing methods. Results: Overall, 1429 patients received a Pima CD4+ test; 500 (35.0%) tests were performed by nurses and 929 (65.0%) were performed by lay health workers. When Pima CD4+ testing was performed by a nurse or a lay health worker, 93.2% and 95.2% of results were valid (p = 0.1); 95.6% and 98.1% of results were received by the patient (p = 0.007); 96.2% and 94.0% of results were received by the patient on the same day (p = 0.08). Overall, 97.2% of Pima CD4+ results were received by patients, compared to 55.4% of standard laboratory CD4+ results (p < 0.001). Conclusions: POC CD4+ testing was feasible and effective when task-shifted to lay health workers. Rollout of POC CD4+ testing via task-shifting can improve access to CD4+ testing and retention in care between HIV diagnosis and antiretroviral therapy initiation in low- and middle-income countries. |
Limited utility of dried-blood- and plasma spot-based screening for antiretroviral treatment failure with Cobas Ampliprep/TaqMan HIV-1 version 2.0.
Sawadogo S , Shiningavamwe A , Chang J , Maher AD , Zhang G , Yang C , Gaeb E , Kaura H , Ellenberger D , Lowrance DW . J Clin Microbiol 2014 52 (11) 3878-83 The 2013 WHO antiretroviral therapy (ART) guidelines recommend dried blood spots (DBS) as an alternative specimen type for viral load (VL) monitoring. We assessed the programmatic utility of screening for ARV treatment failure (TF) at 5,000 and 1,000 copies/mL using DBS and dried plasma spots (DPS) with a commonly used VL assay, the Roche COBAS Ampliprep/COBAS TaqManV.2.0 (CAP/CTM). Plasma, DBS, and DPS were prepared from 839 whole-blood specimens collected from patients on ART ≥ six months at three public facilities in Namibia. VL was measured in plasma, DBS and DPS using the CAP/CTM and results were compared using plasma VL as the reference standard. The clinical sensitivity, specificity, Positive and Negative Predictive Value, (PPV and NPV) of DBS were 0.99, 0.55, 0.33 and 0.99, and 0.99, 0.26, 0.29 and 0.99 at ARV TF diagnostic thresholds of 5,000 copies/mL and 1,000 copies/mL, respectively; for DPS, they were 0.88, 0.98, 0.92 and 0.97, and 0.91, 0.96, 0.89, and 0.97 at TF diagnostic thresholds of 5,000 copies/mL and 1,000 copies/mL, respectively. TF prevalence in DBS was overestimated by 33% and 57% at the two thresholds, respectively. A high rate of false-positive results would occur if the CAP/CTM with DBS were used to screen for ARV TF. WHO recommendations for DBS-based VL monitoring should be specific to VL assay version and type. Despite the higher performance of DPS, the programmatic utility for TF screening may be limited by requirements for processing the whole blood at the collection site. |
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