Search

Background: HIV self-testing (HIVST) may increase HIV testing uptake, facilitating earlier treatment for key populations like MSM who experience barriers accessing clinic-based HIV testing. HIVST usability among African MSM has not been explored. Methods: We assessed usability of oral fluid (OF) and fingerstick (FS; blood) HIVST kits during three phases among MSM with differing degrees of HIVST familiarity in Mpumalanga, South Africa. In 2015, 24 HIVST-naïve MSM conducted counselor-observed OF and FS HIVST after brief demonstration. In 2016 and 2017, 45 and 64 MSM with experience using HIVST in a pilot study chose one HIVST to conduct with a counselor-observer present. In addition to written, the latter group had access to video instructions. We assessed frequency of user errors and reported test use ease, changes in error frequency by phase, and covariates associated with correct usage using log-Poisson and Gaussian generalized estimating equations. Results: Among OF users (n = 57), 15–30% committed errors in each phase; however, observers consistently rated participants as able to test alone. Among FS users (n = 100), observers noted frequent errors, most commonly related to blood collection and delivery. We found suggestive evidence (not reaching statistical significance) that user errors decreased, with 37.5%, to 28.1%, and 18.2% committing errors in phases I, II, and III, respectively (p-value:0.08), however observer concerns remained constant. Ease and confidence using HIVST increased with HIV testing experience. Participants using three HIVST were more likely (RR:1.92, 95% CI:1.32, 2.80) to report ease compared to those without prior HIVST experience. Never testers (RR:0.66, 95% CI:0.44–0.99) reported less ease performing HIVST compared to participants testing in the past six months. Conclusions: MSM were able to perform the OF test. Fingerstick test performance was less consistent; however preference for fingerstick was strong and performance may improve with exposure and instructional resources. Continued efforts to provide accessible instructions are paramount. [ABSTRACT FROM AUTHOR]

Background: Samples submitted for HIV PCR testing that fail to yield a positive or negative result represent missed diagnostic opportunities. We describe HIV PCR test rejections and indeterminate results, and the associated delay in diagnosis, within South Africa’s early infant diagnosis (EID) program from 2010 to 2015. Methods: HIV PCR test data from January 2010 to December 2015 were extracted from the National Health Laboratory Service Corporate Data Warehouse, a central data repository of all registered test-sets within the public health sector in South Africa, by laboratory number, result, date, facility, and testing laboratory. Samples that failed to yield either a positive or negative result were categorized according to the rejection code on the laboratory information system, and descriptive analysis performed using Microsoft Excel. Delay in diagnosis was calculated for patients who had a missed diagnostic opportunity registered between January 2013 and December 2015 by means of a patient linking-algorithm employing demographic details. Results: Between 2010 and 2015, 2 178 582 samples were registered for HIV PCR testing of which 6.2% (n = 134 339) failed to yield either a positive or negative result, decreasing proportionally from 7.0% (n = 20 556) in 2010 to 4.4% (n = 21 388) in 2015 (p<0.001). Amongst 76 972 coded missed diagnostic opportunities, 49 585 (64.4%) were a result of pre-analytical error and 27 387 (35.6%) analytical error. Amongst 49 694 patients searched for follow-up results, 16 895 (34.0%) had at least one subsequent HIV PCR test registered after a median of 29 days (IQR: 13–57), of which 8.4% tested positive compared with 3.6% of all samples submitted for the same period. Conclusions: Routine laboratory data provides the opportunity for near real-time surveillance and quality improvement within the EID program. Delay in diagnosis and wastage of resources associated with missed diagnostic opportunities must be addressed and infants actively followed-up as South Africa works towards elimination of mother-to-child transmission. [ABSTRACT FROM AUTHOR]

Background: Expansion of HIV viral load (VL) testing services are required to meet increased targets for monitoring patients on antiretroviral treatment. South Africa currently tests >4million VLs per annum in 16 highly centralised, automated high-throughput laboratories. The Xpert HIV-1 VL assay (Cepheid) was evaluated against in-country predicates, the Roche Cobas Taqmanv2 and Abbott HIV-1RT, to investigate options for expanding VL testing using GeneXpert’s random access, polyvalent capabilities and already established footprint in South Africa with the Xpert MTB/RIF assay (207 sites). Additionally, the performance of Xpert HIV-1VL on alternative, off-label specimen types, Dried Blood Spots (DBS) and whole blood, was investigated. Method: Precision, accuracy (agreement) and clinical misclassification (1000cp/ml) of Xpert HIV-1VL plasma was compared to Taqmanv2 (n = 155) and Abbott HIV-1 RT (n = 145). Misclassification of Xpert HIV-1VL was further tested on DBS (n = 145) and whole blood (n = 147). Results: Xpert HIV-1VL demonstrated 100% concordance with predicate platforms on a standardised frozen, plasma panel (n = 42) and low overall percentage similarity CV of 1.5% and 0.9% compared to Taqmanv2 and Abbott HIV-1 RT, respectively. On paired plasma clinical specimens, Xpert HIV-1VL had low bias (SD 0.32–0.37logcp/ml) and 3% misclassification at the 1000cp/ml threshold compared to Taqmanv2 (fresh) and Abbott HIV-1 RT (frozen), respectively. Xpert HIV-1VL on whole blood and DBS increased misclassification (upward) by up to 14% with increased invalid rate. All specimen testing was easy to perform and compatible with concurrent Xpert MTB/RIF Tuberculosis testing on the same instrument. Conclusion: The Xpert HIV-1VL on plasma can be used interchangeably with existing predicate platforms in South Africa. Whole blood and DBS testing requires further investigation, but polyvalency of the GeneXpert offers a solution to extending VL testing services. [ABSTRACT FROM AUTHOR]

Background: High BMI and blood pressure are leading chronic disease risk factors in South Africa. Longterm effects of HIV and ART on adiposity and blood pressure are poorly understood, and direct comparisons of risk factor trajectories in HIV- versus HIV+ populations are rare. Methods: In 2003 and 2010, height, weight, and blood pressure were recorded in a study population (n = 505) in KwaZulu-Natal, South Africa (30% adult HIV prevalence). We modeled change in BMI and BP longitudinally in HIV- individuals (n = 315), seroconverters (n = 32), HIV+ patients not on ART (HIV+ART−; n = 52), HIV+ patients on ART for 0–<2 years as of 2010 (HIV+ART0–<2 yrs; n = 18), patients on ART for 2–5 years (HIV+ART2–5yrs; n = 44), and a subgroup with unknown HIV status (n = 44). Difference-in-differences were assessed in reference to the HIV- population. Results: Between 2003 and 2010, BMI increased significantly in the HIV- group, by 0.874 (95% CI 0.339, 1.41; p = 0.001), to 30.4. BMI drop was significantly greater in HIV+ART0-<2yrs than in HIV+ART2–5yrs (p = 0.005). DID in BMI in HIV+ART0-<2yrs versus the reference was -5.21 (95% CI -7.53, -2.90; p = 0.001), and DID in HIV+ART2–5yrs versus reference was -1.35 (95% CI -2.89, 0.189; p = 0.086). DID in SBP in HIV+ART−vs HIV- DID was -7.55 mmHg (95% CI -13.2 to -1.90; p = 0.009). Conclusion: Short-term ART (0–<2 years) was associated with larger weight loss than either no ART or long-term ART. Once on ART for 2+ years, individuals ‘caught up’ on weight gain with the HIV- population. Our results showcase the importance of health system readiness to address the burgeoning double burden of disease in South Africa. [ABSTRACT FROM AUTHOR]

Background: The BD-FACSPresto™ CD4 is a new, point-of-care (POC) instrument utilising finger-stick capillary blood sampling. This study evaluated its performance against predicate CD4 testing in South Africa. Methods: Phase-I testing: HIV+ patient samples (n = 214) were analysed on the Presto™ under ideal laboratory conditions using venous blood. During Phase-II, 135 patients were capillary-bled for CD4 testing on FACSPresto™, performed according to manufacturer instruction. Comparative statistical analyses against predicate PLG/CD4 method and industry standards were done using GraphPad Prism 6. It included Bland-Altman with 95% limits of agreement (LOA) and percentage similarity with coefficient of variation (%CV) analyses for absolute CD4 count (cells/μl) and CD4 percentage of lymphocytes (CD4%). Results: In Phase-I, 179/217 samples yielded reportable results with Presto™ using venous blood filled cartridges. Compared to predicate, a mean bias of 40.4±45.8 (LOA of -49.2 to 130.2) and %similarity (%CV) of 106.1%±7.75 (7.3%) was noted for CD4 absolute counts. In Phase-2 field study, 118/135 capillary-bled Presto™ samples resulted CD4 parameters. Compared to predicate, a mean bias of 50.2±92.8 (LOA of -131.7 to 232) with %similarity (%CV) 105%±10.8 (10.3%), and 2.87±2.7 (LOA of -8.2 to 2.5) with similarity of 94.7±6.5% (6.83%) noted for absolute CD4 and CD4% respectively. No significant clinical differences were indicated for either parameter using two sampling methods. Conclusion: The Presto™ produced remarkable precision to predicate methods, irrespective of venous or capillary blood sampling. A consistent, clinically insignificant over-estimation (5–7%) of counts against PLG/CD4 and equivalency to FACSCount™ was noted. Further field studies are awaited to confirm longer-term use. [ABSTRACT FROM AUTHOR]