Low levels of viral suppression among refugees and host nationals accessing antiretroviral therapy in a Kenyan refugee camp.

BACKGROUND: Refugees and host nationals who accessed antiretroviral therapy (ART) in a remote refugee camp in Kakuma, Kenya (2011-2013) were compared on outcome measures that included viral suppression and adherence to ART. METHODS: This study used a repeated cross-sectional design (Round One and Round Two). All adults (≥18 years) receiving care from the refugee camp clinic and taking antiretroviral therapy (ART) for ≥30 days were invited to participate. Adherence was measured by self-report and monthly pharmacy refills. Whole blood was measured on dried blood spots. HIV-1 RNA was quantified and treatment failures were submitted for drug resistance testing. A remedial intervention was implemented in response to baseline testing. The primary outcome was viral load <5000 copies/mL. The two study rounds took place in 2011-2013. RESULTS: Among eligible adults, 86% (73/85) of refugees and 84% (86/102) of Kenyan host nationals participated in the Round One survey; 60% (44/73) and 58% (50/86) of Round One participants were recruited for Round Two follow-up viral load testing. In Round One, refugees were older than host nationals (median age 36 years, interquartile range, IQR 31, 41 vs 32 years, IQR 27, 38); the groups had similar time on ART (median 147 weeks, IQR 38, 64 vs 139 weeks, IQR 39, 225). There was weak evidence for a difference between proportions of refugees and host nationals who were virologically suppressed (<5000 copies/mL) after 25 weeks on ART (58% vs 43%, p = 0.10) and no difference in the proportions suppressed at Round Two (74% vs 70%, p = 0.66). Mean adherence within each group in Round One was similar. Refugee status was not associated with viral suppression in multivariable analysis (adjusted odds ratio: 1.69, 95% CI 0.79, 3.57; p = 0.17). Among those not suppressed at either timepoint, 69% (9/13) exhibited resistance mutations. CONCLUSIONS: Virologic outcomes among refugees and host nationals were similar but unacceptably low. Slight improvements were observed after a remedial intervention. Virologic monitoring was important for identifying an underperforming ART program in a remote facility that serves refugees alongside host nationals. This work highlights the importance of careful laboratory monitoring of vulnerable populations accessing ART in remote settings.

Evaluation of quantification of HIV-1 RNA viral load in plasma and dried blood spots by use of the semiautomated Cobas Amplicor assay and the fully automated Cobas Ampliprep/TaqMan assay, version 2.0, in Kisumu, Kenya.

In Kenya, HIV-1 viral load monitoring is commonly performed with the Cobas Amplicor using plasma specimens. Interest is growing in transitioning to real-time PCR (RT-PCR), such as the Cobas Ampliprep/Cobas TaqMan (CAP/CTM), using dried blood spots (DBS). Before implementation, direct evaluation of the two assays using DBS field specimens is required. This study compares the sensitivity, specificity, negative and positive predictive values (NPV and PPV, respectively), concordance, and agreement between HIV-1 viral load measurements using plasma and DBS specimens obtained from 512 HIV-1-infected pregnant females enrolled in the Kisumu Breastfeeding Study and tested with the Cobas Amplicor and CAP/CTM assays. The sensitivity and NPV of viral load detection in DBS specimens were higher with CAP/CTM (sensitivity, 100%; 95% confidence interval [CI], 99.1 to 100.0%; NPV, 100%; 95% CI, 59.0 to 100.0%) than the Cobas Amplicor (sensitivity, 96.6%; 95% CI, 94.3 to 98.1%; NPV, 58.8%; 95% CI, 40.7 to 75.4%). The PPVs were comparable between both assays when using DBS. The specificity of viral load detection in DBS specimens was lower with CAP/CTM (77.8%; 95% CI, 40.0 to 97.2%) than that of the Cobas Amplicor (95.2%; 95% CI, 76.2 to 99.9%). Good concordance and agreement were observed when paired plasma and DBS specimens were tested with both assays. Lower specificity with the CAP/CTM is likely due to proviral HIV-1 DNA amplification and lower detection limits with RT-PCR. However, the CAP/CTM has better sensitivity and higher throughput than the Cobas Amplicor. These findings suggest that DBS may be a suitable alternative to plasma when using RT-PCR, which could increase access to viral load monitoring in resource-limited settings.

CD4, viral load response, and adherence among antiretroviral-naive breast-feeding women receiving triple antiretroviral prophylaxis for prevention of mother-to-child transmission of HIV in Kisumu, Kenya.

BACKGROUND: Health benefits and survival of an exclusively breast-fed infant is dependent on the mother's health; thus, the need for antiretroviral (ARV) intervention for prevention of mother-to-child transmission (PMTCT). Achieving maternal health benefits from these regimens requires adherence to the treatments and close monitoring. We evaluated virologic, immunologic responses, and adherence among women receiving maternal triple ARV prophylaxis consisting of lamivudine/zidovudine and nevirapine or nelfinavir in the Kisumu Breastfeeding Study. METHODS: We analyzed baseline demographic data, trends in CD4 count, and viral load (VL) at enrollment (32-34 weeks gestation), delivery, 14 and 24 weeks postpartum among 434 women who remained in the study at 24 weeks postpartum. Adherence rates were determined using pill counts reinforced by self-report and drug calendar. We dichotomized adherence as ≥95% versus <95%. RESULTS: Among the 434 women, 84% (n = 366) had adherence ≥95%. The proportion of women with undetectable VL (<400 copies/mL) increased from 6% at baseline to 79%, and that of those with CD4 count <250 cells per microliter decreased from 23% (100) at baseline to 5% (22) at 24 weeks postpartum. In discrete-survival model, time to achieving VL suppression was associated with baseline VL <5.0 log copies per milliliter, parity ≥2, and use of nelfinavir- versus nevirapine-based ARV. Association between undetectable VL with duration of therapy (P < 0.0001) and adherence with suppression of VL (P = 0.001) was observed. CONCLUSIONS: High baseline VL and short exposure to ARVs for PMTCT are risk factors for failing to achieve undetectable VL. These findings support the new WHO guidelines for early initiation of ARV prophylaxis for PMTCT for maximal reduction of maternal VL.

Comparison of HIV-1 detection in plasma specimens and dried blood spots using the Roche COBAS Ampliscreen HIV-1 test in Kisumu, Kenya.

The World Health Organization recommends screening donor blood for HIV in centralized laboratories. This recommendation contributes to quality, but presents specimen transport challenges for resource-limited settings which may be relieved by using dried blood spots (DBS). In sub-Saharan Africa, most countries screen donor blood with serologic assays only. Interest in window period reduction has led blood services to consider adding HIV nucleic acid testing (NAT). The U.S. Food and Drug Administration (FDA) mandates that HIV-1 NAT blood screening assays have a 95% detection limit at or below 100 copies/ml and 5000 copies/ml for pooled and individual donations, respectively. The Roche COBAS Ampliscreen HIV-1 test, version 1.5, used for screening whole blood or components for transfusion, has not been tested with DBS. We compared COBAS Ampliscreen HIV-1 RNA detection limits in DBS and plasma. An AIDS Clinical Trials Group, Viral Quality Assurance laboratory HIV-1 standard with a known viral load was used to create paired plasma and DBS standard nine member dilution series. Each was tested in 24 replicates with the COBAS Ampliscreen. A probit analysis was conducted to calculate 95% detection limits for plasma and DBS, which were 23.8 copies/ml (95% CI 15.1-51.0) for plasma and 106.7 copies/ml (95% CI 73.8-207.9) for DBS. The COBAS Ampliscreen detection threshold with DBS suggests acceptability for individual donations, but optimization may be required for pooled specimens.