Implementation of Antibody Rapid Diagnostic Testing versus Real-Time Reverse Transcription-PCR Sample Pooling in the Screening of COVID-19: a Case of Different Testing Strategies in Africa

COVID-19 has wreaked havoc across the globe, although cases in Africa remain lower than 50 other regions but they are gradually on an upward trajectory. To date, COVID-19 cases have 51 been reported in 54 countries. However, due to limited SARS-COV-2 rRT-PCR testing 52 capacity and scarcity of testing reagents, it is probable that the total number of cases could 53 far exceed published statistics. In this viewpoint, using Ghana, Malawi, South Africa and 54 Zimbabwe as examples of countries that have implemented different testing strategies, we 55 argue that the implementation of sample pooling for rRT-PCR over antibody rapid diagnostic 56 testing could have a greater impact in assessing disease burden. Sample pooling offers huge 57 advantages compared to single test rRT-PCR, as it lowers experimental costs, personnel 58 time, reduces burnout and analytical run-times. Africa is already strained in terms of testing 59 resources for COVID-19, hence cheaper alternative ways need to be implemented to 60 conserve resources, maximise on mass testing and reduce transmission in the wider 61 population

Comparison of non-invasive methods of assessing liver fibrosis in combination ART-experienced Zimbabweans

Background: The prevalence of morbidity and mortality associated with liver disease among HIV-infected individuals on combination antiretroviral therapy (ART) is high. Early screening of liver disease is essential, as it provides an opportunity for successful treatment. Hence, there is a need for reliable, inexpensive and non-invasive early markers of hepatic damage. Objectives: Non-invasive algorithms are available for assessing the extent of liver fibrosis as markers of ongoing inflammatory damage. This study compared the use of the FibroTest, Fibrosis-4 (FIB-4) index, APRI test and AST:ALT ratio in assessing liver fibrosis in combination ART-experienced individuals. Methods: In a comparative cross-sectional study, 79 participants between the ages of 8 and 62 years were recruited. The performance of each fibrosis algorithm was determined using established cut-off scores for clinically significant liver fibrosis. Results: The prevalence of liver fibrosis as determined by the FibroTest, FIB-4 index, APRI test and AST: ALT ratio were 19.0%, 21.5%, 12.7% and 79.7%, respectively. For individual biomarkers, A-2M concentration (p < 0.001) and AST activity (p = 0.003) remained significantly elevated in participants with fibrosis than those without as defined by FibroTest and APRI test, respectively, after adjustments for multiple comparisons. Conclusion: Our data demonstrate a high prevalence of asymptomatic liver fibrosis among combination ART-experienced individuals in Zimbabwe, and this warrants adequate monitoring of liver fibrosis in individuals on ART. Discordance of fibrosis results among the algorithms and individual biomarkers and calls for further work in identifying optimal biomarkers for detection of asymptomatic fibrosis

Dried blood spot omega-3 and omega-6 long chain polyunsaturated fatty acid levels in 7–9 year old Zimbabwean children: a cross sectional study

Background Omega-3 long chain-polyunsaturated fatty acids (LC-PUFAs)–docosahexaenoic acid (DHA), docosapentaenoic acid (DPA) and eicosapentaenoic acid (EPA)– and omega-6 LC-PUFA arachidonic acid (ARA), are essential for optimum physical and mental development in children. Prior to this study, the blood omega-3 LC-PUFA levels were unknown in Zimbabwean children, particularly in those aged 7–9 years, despite the documented benefits of LC-PUFAs. Documentation of the LC-PUFA levels in this age group would help determine whether interventions, such as fortification, are necessary. This study aimed to determine dried whole blood spot omega-3 and omega-6 LC-PUFA levels and LC-PUFA reference intervals among a selected group of Zimbabwean children aged 7–9 years old. Methods We conducted a cross sectional study from September 2011 to August 2012 on a cohort of peri-urban, Zimbabwean children aged 7–9 years. The children were born to mothers enrolled at late pregnancy into an HIV prevention program between 2002 and 2004. Dried whole blood spots were sampled on butylated hydroxytoluene antioxidant impregnated filter papers and dried. LC-PUFAs were quantified using gas liquid chromatography. Differences in LC-PUFAs between groups were compared using the Kruskal Wallis test and reference intervals determined using non-parametric statistical methods. Results LC-PUFAs levels were determined in 297 Zimbabwean children of whom 170 (57.2 %) were girls. The study determined that LC-PUFAs (wt/wt) ranges were EPA 0.06–0.55 %, DPA 0.38–1.98 %, DHA 1.13–3.52 %, ARA 5.58–14.64 % and ARA: EPA ratio 15.47–1633.33. Sixteen participants had omega-3 LC-PUFAs levels below the determined reference intervals, while 18 had higher omega-6 LC-PUFAs. The study did not show gender differences in omega-3 and omega-6 LC-PUFAs levels (all p > 0.05). EPA was significantly higher in the 8 year age group compared to those aged 7 and 9 years (median; 0.20 vs 0.17 vs 0.18, respectively, p = 0.049). ARA: EPA ratio was significantly higher in the 7 year age group compared to those aged 8 and 9 years (median; 64.38 vs 56.43 vs 55.87 respectively, p = 0.014). Conclusions In this cohort of children, lower EPA levels and higher ARA: EPA ratios were observed compared to those reported in apparently healthy children elsewhere. The high ARA: EPA ratios might increase the vulnerability of these children to inflammatory pathologies. Identification and incorporation into diet of locally produced foodstuffs rich in omega-3 LC-PUFAs is recommended as well as advocating for dietary supplementation with omega-3 fish oils and algae based oils

Comparison of non-invasive methods of assessing liver fibrosis in combination ART-experienced Zimbabweans

CITATION: Nherera, B. et al. 2019. Comparison of non-invasive methods of assessing liver fibrosis in combination ART-experienced Zimbabweans. Southern African Journal of HIV Medicine, 20(1):a844, doi.org/10.4102/sajhivmed.v20i1.844.The original publication is available at https://sajhivmed.org.zaBackground: The prevalence of morbidity and mortality associated with liver disease among HIV-infected individuals on combination antiretroviral therapy (ART) is high. Early screening of liver disease is essential, as it provides an opportunity for successful treatment. Hence, there is a need for reliable, inexpensive and non-invasive early markers of hepatic damage. Objectives: Non-invasive algorithms are available for assessing the extent of liver fibrosis as markers of ongoing inflammatory damage. This study compared the use of the FibroTest, Fibrosis-4 (FIB-4) index, APRI test and AST:ALT ratio in assessing liver fibrosis in combination ART-experienced individuals. Methods: In a comparative cross-sectional study, 79 participants between the ages of 8 and 62 years were recruited. The performance of each fibrosis algorithm was determined using established cut-off scores for clinically significant liver fibrosis. Results: The prevalence of liver fibrosis as determined by the FibroTest, FIB-4 index, APRI test and AST: ALT ratio were 19.0%, 21.5%, 12.7% and 79.7%, respectively. For individual biomarkers, A-2M concentration ( p < 0.001) and AST activity ( p = 0.003) remained significantly elevated in participants with fibrosis than those without as defined by FibroTest and APRI test, respectively, after adjustments for multiple comparisons. Conclusion: Our data demonstrate a high prevalence of asymptomatic liver fibrosis among combination ART-experienced individuals in Zimbabwe, and this warrants adequate monitoring of liver fibrosis in individuals on ART. Discordance of fibrosis results among the algorithms and individual biomarkers and calls for further work in identifying optimal biomarkers for detection of asymptomatic fibrosis.Publisher's versio

Higher serum 25-hydroxyvitamin D concentrations are associated with active pulmonary tuberculosis in hospitalised HIV infected patients in a low income tropical setting: a cross sectional study

Abstract Background The inherent risk of developing tuberculosis (TB) in HIV- infected individuals is further enhanced by hypovitaminosis D. Interventions that offset HIV-associated immune deterioration potentially arrest disease progression and incidence of opportunistic infections including TB. Despite conflicting reports on association between vitamin D deficiency (VDD) and risk of TB, vitamin D (VD) supplementation remains a promising intervention. Methods We conducted a comparative cross-sectional study on 145 HIV+/pulmonary TB+ (PTB) and 139 HIV+/PTB− hospitalised patients to investigate association of vitamin D status and risk of PTB. Stratified random sampling was used to select archived serum specimens from participants enrolled in a randomised controlled trial (RCT) conducted to investigate the impact of using a point-of-care urine lipoarabinomannan strip test for TB diagnosis. PTB status was confirmed using sputum smear microscopy, culture or GeneXpert MTB/RIF. Serum 25-hydroxyvitamin D [25(OH) D] concentrations were assayed by competitive chemiluminescent immunoassay prior to commencement of anti-TB treatment. Effect of VD status on duration of hospital stay and patient outcomes on follow up at 8 weeks were also investigated. Median serum 25(OH) D concentrations were compared using Mann-Whitney test and covariates of serum VD status were assessed using logistic regression analysis. Results Overall VDD prevalence in the cohort was 40.9% (95% CI: 35.1–46.8). Median serum 25(OH)D concentrations were significantly higher in HIV+/PTB+ group (25.3 ng/ml, IQR:18.0–33.7) compared to the HIV+/PTB− group (20.4 ng/ml, IQR:14.6–26.9), p = 0.0003. Patients with serum 25(OH) D concentration ≥ 30 ng/ml were 1.9 times more likely to be PTB+ compared to those with serum 25(OH) D concentrations < 30 ng/ml (odds ratio (OR) 1.91; 95% CI 1.1–3.2). PTB-related death was associated with higher odds of having 25(OH) D levels≥30 ng/ml. Age, gender, CD4+ count, combination antiretroviral therapy (cART) status, efavirenz based cART regimen and length of hospital stay were not associated with vitamin D status. Conclusions The finding of an association between higher serum 25(OH) D concentrations and active PTB and TB-related mortality among hospitalised HIV-infected patients in the present study is at variance with the commonly reported association of hypovitaminosis and susceptibility to TB. Our findings though, are in concordance with a small pool of reports from other settings

Prevalence of lipodystrophy and metabolic abnormalities in HIV-infected African children after 3 years on first-line antiretroviral therapy.

BACKGROUND: Most pediatric lipodystrophy data come from high-income/middle-income countries, but most HIV-infected children live in sub-Saharan Africa, where lipodystrophy studies have predominantly investigated stavudine-based regimens. METHODS: Three years after antiretroviral therapy (ART) initiation, body circumferences and skinfold thicknesses were measured (n = 590), and fasted lipid profile assayed (n = 325), in children from 2 ARROW trial centres in Uganda/Zimbabwe. Analyses compared randomization to long-term versus short-term versus no zidovudine from ART initiation [unadjusted; latter 2 groups receiving abacavir+lamivudine+non-nucleoside-reverse-transciptase-inhibitor (nNRTI) long-term], and nonrandomized (confounder-adjusted) receipt of nevirapine versus efavirenz. RESULTS: Body circumferences and skinfold thicknesses were similar regardless of zidovudine exposure (P &gt; 0.1), except for subscapular and supra-iliac skinfolds-for-age which were greater with long-term zidovudine (0.006 &lt; P &lt; 0.047). Circumferences/skinfolds were also similar with efavirenz and nevirapine (adjusted P &gt; 0.09; 0.02 &lt; P &lt; 0.03 for waist/waist-hip-ratio). Total and high-density lipoprotein (HDL)-cholesterol, HDL/triglyceride-ratio (P &lt; 0.0001) and triglycerides (P = 0.01) were lower with long-term zidovudine. Low-density lipoprotein (LDL)-cholesterol was higher with efavirenz than nevirapine (P &lt; 0.001). Most lipids remained within normal ranges (75% cholesterol, 85% LDL and 100% triglycerides) but more on long-term zidovudine (3 NRTI) had abnormal HDL-cholesterol (88% vs. 40% short/no-zidovudine, P &lt; 0.0001). Only 8/579(1.4%) children had clinical fat wasting (5 grade 1; 3 grade 2); 2(0.3%) had grade 1 fat accumulation. CONCLUSIONS: Long-term zidovudine-based ART is associated with similar body circumferences and skinfold thicknesses to abacavir-based ART, with low rates of lipid abnormalities and clinical lipodystrophy, providing reassurance where national programs now recommend long-term zidovudine. Efavirenz and nevirapine were also similar; however, the higher LDL observed with efavirenz and lower HDL observed with zidovudine suggests that zidovudine+lamivudine+efavirenz should be investigated in future