Direct biomarkers of microbial translocation as predictors of immune activation in adult Zambians with environmental enteropathy and hepatosplenic schistosomiasis.

Thesis of of Doctor of Philosophy in ImmunologyBackground: Microbial translocation is a poorly understood consequence of several disorders such as environmental enteropathy (EE) and hepatosplenic schistosomiasis (HSS) disease. Direct biomarkers of microbial translocation such lipopolysaccharide, 16S rRNA gene and Toll-like receptor ligands may predict immune activation. This study evaluated whether direct biomarkers of microbial translocation correlate and predict immune activation in adult Zambians with EE and HSS disease. The public health importance of biomarkers is that they can be used to predict individuals with EE or HSS who are likely to develop chronic immune activation or are at risk. The biomarkers may be used for early diagnosis and stratify for any treatment or intervention. Methods: An unmatched case-control study was conducted in participants with EE (n=67) recruited from Misisi compound, Lusaka, Zambia, with two comparison groups, HSS participants (n=86) from The University Teaching Hospital and healthy controls (n=41). Plasma lipopolysaccharide (LPS) was measured by Limulus Amoebocyte Lysate Assay, plasma 16S rRNA gene copy number was quantified by quantitative real-time PCR, Toll-like receptor ligands (TLRLs) activity by QUANTI-Blue detection medium, plasma biomarkers of host response (C-reactive protein, soluble CD14, soluble CD163 and lipopolysaccharide-binding protein) to microbial translocation were measured by ELISA and cytokines (TNF-α, IL-6, IL-10, IL-4, IL-2, IFN-γ and IL-17) from cell culture supernatant by Cytometric Bead Array. Results: Plasma lipopolysaccharide levels were elevated in EE group with median 378.9 (IQR, 82.7 - 879.5) EU/ml compared to participants with HSS with median 213.1 (IQR, 77.2 - 358.3) EU/ml; p=0.03 or healthy controls with median 202.3 (IQR, 43.2 - 251.1) EU/ml; p=0.01. The 16S rRNA copy number were significantly elevated in the EE group with median 2651 (IQR, 529 – 8779) copies/μl compared to the levels in participants with HSS with median 387 (IQR, 165 – 1990) copies/μl; p<0.001) or healthy controls with median 193 (IQR, 132 – 455) copies/μl; p<0.001. TLRLs activity was significantly higher in the EE group with median 0.49 (IQR, 0.0 - 0.8) OD units than in participants with HSS with median 0.13 (IQR, 0.0 - 0.8) OD units; p=0.01 or the healthy controls with median 0.02 (IQR, 0.0 - 0.12) OD units; p=0.004. Participants with HSS had higher TLRLs activity compared to healthy controls p=0.02. In multivariate multiple regression models LPS, 16S rRNA copy number, and TLRL activity were independent predictors of cytokines while controlling for baseline characteristics. In the EE group, a good model fit was obtained (R2 = 0.526, F = 47.53, p < 0.001) which predicted TNF-α, IL-6, and IL-10. In the HSS group, a less impressive but still significant fit was obtained (R2 = 0.382, F = 22.43, p = 0.002 which predicted 16S rRNA and TLRLs. In healthy controls, no satisfactory model was obtained (R2 = 0.040, F =1.03, p = 0.38). Conclusions: Direct biomarkers of microbial translocation were higher in EE and HSS participants compared to healthy controls. The biomarkers seems to correlate and predict immune activation in individuals with EE and HSS infection. This data support the model that proposes that biomarkers of microbial origin in the gastrointestinal tract move across a vii compromised intestinal barrier leading to heightened immune activation in conditions with intestinal barrier dysfunction. The study recommends measurement of microbial translocation using these biomarkers. They are cheaper, practical and non-invasive

Prevalence and Determinants of Virological Non-Suppression Among HIV Infected Adolescents on Antiretroviral Treatment At Kanyama General Hospital, Lusaka, Zambia

Background Zambia continues to face challenges in addressing the HIV epidemic among adolescents. Despite implementing various interventions to improve viral suppression among adolescents, the proportion of adolescents achieving viral load (VL) suppression remains low compared to the adults, and below the Joint United Nations Programme on HIV/AIDS (UNAIDS) 95% target. Therefore, the study estimated the proportion and determined the factors associated with non-suppression among HIV infected adolescents on antiretroviral treatment at Kanyama General Hospital, Lusaka, Zambia Methods A cross-sectional study was conducted using routinely collected data from SmartCare on adolescents (10 – 19 years) receiving ART for the period 1st January 2020 to 30th September 2022. Demographic and clinic characteristics data was extracted. The study defined virological non-suppression as having VL count ≥1000 RNA copies/mL. The study used multivariable logistic regression to identify factors associated with virological non-suppression. Data analysis was conducted in Stata 14. Results Of the 415 study participants, majority were 15-19 years (62.4%, 259/415) were female (56.6%, 235/415). The proportion of non-suppression was 5.8% (24/415, 95% CI=0.04-0.08). Age and sex showed no significant association with virological non-suppression, indicated by p-values of 0.089 and 0.310, respectively. Both treatment duration on ART and current treatment line were identified as determinants of virological non-suppression, with treatment duration on ART showing slightly decreased odds of (AOR=0.99, 95% CI=0.98-1.00) and being on the 2nd treatment line/regimen was associated with increased odds (AOR=8.09, 95% CI=2.71-24.17) of virological non-suppression. Conclusion The study found a prevalence of 5.8% virological non-suppression among adolescents. Treatment duration on ART and 2nd treatment line/regimen were found as determinants of virological non-suppression. Need to continuously monitor adolescent’s treatment duration on ART to avoid them moving 2nd treatment line/regimen

Comparison of Viral Load Suppression among HIV-1 Infected Children Aged 5 to 12 Years on Once Daily Versus Twice Daily Abacavir-Containing Regimens at University Teaching Hospitals - Children’s Hospital, Lusaka, Zambia

Abacavir is one of the first-line drugs used to treat HIV infection in paediatric patients in Zambia, whose use in children has not been widely published. This study compared the virologic response of abacavir given as part of a once-daily regimen with the response when given as part of a twice-daily regimen. A total of eighty-two children aged two to twelve years currently receiving antiretroviral therapy at the Paediatric Centre of Excellence, University Teaching Hospitals, Lusaka, Zambia, were observed in the study. This was a prospective cohort study. All the children were initially on twice daily abacavir containing regimen with lamivudine twice daily and efavirenz once daily, with 40 maintained on this regimen by the attending clinician and 42 switched to once-daily abacavir, lamivudine and efavirenz by the attending clinician. Profiles were obtained for each child to compare viral load at baseline and week 24. Data was analysed using Stata Version 16.The proportion of children with undetectable viral load in the once-daily group at twenty-four weeks was 64.3 per cent compared to 72.5 per centin the twice-daily group. Twice-daily dosing reduced the odds of achieving an undetectable viral load by about 59 per cent, while being male reduced the odds of achieving an undetectable HIV viral load by 19.6 per cent. Baseline haemoglobin, creatinine, or alanine transferase levels were not predictors of viral load suppression.The study suggests that once-daily dosing of an abacavir-containing regimen achieved a lower viral suppression rate when compared to twice-daily dosing. It is recommended that once-daily dosing of abacavir containing regimen should be considered as a dosing option for Zambian children living with HIV

Effects of medication knowledge on medication adherence among hypertensive patients at Matero level one hospital, Lusaka city, Zambia: a cross sectional study

Background: Medication adherence is the mainstay to good treatment outcomes. Failure to adhere to medication in hypertensive patients may lead to considerable deterioration of the disease resulting in increased costs of healthcare and mortality. Knowledge about the name of the drug, indications and side effects may enhance medication adherence. Therefore, the aim of this study was to assess effects of medication knowledge on medication adherence among hypertensive patients.Methods: This was a cross-sectional study that involved 120 hypertensive patients. A structured questionnaire was used to collect data on demographic characteristics. Adherence was assessed using the 8-item Morisky medication adherence scale while patient’s medication knowledge was assessed using a 7-item scale. Multiple logistic regression was used to assess factors associated with medication adherence.Results: The mean age of participants was 59 years (SD±14.9) and 10 (8.3%), 42 (35%) and 68 (56.7%) had adequate, average and poor medication knowledge respectively. The prevalence of adherence in this study was 37.5%. In multivariable logistic regression analysis, uncontrolled blood pressure (BP) (AOR: 0.38, CI: 0.16-0.90) was associated with lower likelihood of adhering to medication.Conclusions: The adherence level to treatment was low and medication knowledge of hypertensive patients was generally poor. Uncontrolled BP was associated with non-adherence. Patients with uncontrolled hypertension should be given health education and counselling regarding their condition to improve medication adherence.

Improving validity of informed consent for biomedical research in Zambia using a laboratory exposure intervention.

BACKGROUND: Complex biomedical research can lead to disquiet in communities with limited exposure to scientific discussions, leading to rumours or to high drop-out rates. We set out to test an intervention designed to address apprehensions commonly encountered in a community where literacy is uncommon, and where complex biomedical research has been conducted for over a decade. We aimed to determine if it could improve the validity of consent. METHODS: Data were collected using focus group discussions, key informant interviews and observations. We designed an intervention that exposed participants to a detailed demonstration of laboratory processes. Each group was interviewed twice in a day, before and after exposure to the intervention in order to assess changes in their views. RESULTS: Factors that motivated people to participate in invasive biomedical research included a desire to stay healthy because of the screening during the recruitment process, regular advice from doctors, free medical services, and trust in the researchers. Inhibiting factors were limited knowledge about samples taken from their bodies during endoscopic procedures, the impact of endoscopy on the function of internal organs, and concerns about the use of biomedical samples. The belief that blood can be used for Satanic practices also created insecurities about drawing of blood samples. Further inhibiting factors included a fear of being labelled as HIV positive if known to consult heath workers repeatedly, and gender inequality. Concerns about the use and storage of blood and tissue samples were overcome by a laboratory exposure intervention. CONCLUSION: Selecting a group of members from target community and engaging them in a laboratory exposure intervention could be a useful tool for enhancing specific aspects of consent for biomedical research. Further work is needed to determine the extent to which improved understanding permeates beyond the immediate group participating in the intervention

Opuntia stricta cladode Extract reduces blood glucose levels in Alloxan-induced diabetic mice.

Opuntia stricta (commonly called prickly pear cactus) is a natural plant that grows in some parts of Zambia where its fruits and cladodes are commonly consumed for nutritional and medicinal purposes, including glycaemic control among some patients with diabetes mellitus (DM). There is insufficient evidence whether Opuntia stricta indigenously growing in Zambia possess antidiabetic effects.To assess in vivo antidiabetic effects of the aqueous extract of Opuntia stricta cladodes in alloxan-induced diabetic mice. A laboratory-based experimental study was conducted involving 20 adult Swiss albino mice (Mus musculus) weighing 18-30 g. DM was induced using a single intraperitoneal dose of alloxan monohydrate 90 mg/kg. Opuntia stricta aqueous extract was administered orally and blood glucose levels (in mmol/L) monitored daily for 10 days. Alloxan induced a 4- to 5-fold sustained increase in blood glucose levels at 72 hours after administration in mice. Within a 10-day experimental period, Opuntia stricta cladode aqueous extract (1 mg/kg) significantly reduced blood glucose levels in vivo (from 16.6 ± 1.4 mmol/L, 95% CI: 14.9-18.3 at baseline to 7.5 ± 1.0 mmol/L, 95% CI: 6.2-8.9 at endpoint, p < 0.001, n = 5). Similarly, at a dose of 2 mg/kg, the extract significantly reduced blood glucose levels (from 18.7 ± 4.6 mmol/L, 95% CI: 13.0-24.4 at baseline to 6.9 ± 1.7 mmol/L, 95% CI: 4.7-9.0 at endpoint, p = 0.001, n = 5). Opuntia stricta cladode aqueous extract attained a greater reduction in blood glucose levels compared to Glibenclamide 0.25 mg/kg. Opuntia stricta cladode aqueous extract demonstrated a presence of alkaloids, flavonoids, saponins, sterols, carbohydrates, phenols and tannins. Opuntia stricta cladode from Zambia demonstrates antidiabetic effects to reduce blood glucose levels in vivo

A first report of Biomphalaria pfeifferi in the Lower Shire Valley, Southern Malawi, a major intermediate snail host species for intestinal schistosomiasis

The distribution of certain permissive intermediate snail host species in freshwater is a crucial factor shaping transmission of intestinal schistosomiasis, a neglected tropical disease that causes much human suffering in Africa. To shed new light on southern Malawi, where cases of intestinal schistosomiasis have been found, repeated malacological surveys were conducted in Chikwawa and Nsanje Districts in the Lower Shire Valley, to detect and to characterize populations of Biomphalaria, the intermediate host for intestinal schistosomiasis. Sampling took place across a total of 45 freshwater sites, noting water conductivity, pH, temperature, total dissolved salts (TDS) and geographical elevation. The presence or absence of snails was predicted upon physiochemical and environmental conditions in Random Forest modelling. Water conductivity, TDS and geographical elevation were most important in predicting abundance of snails with water temperature and pH of slightly less important roles. This first report of B. pfeifferi in the Lower Shire Valley enhances understanding of the environmental factors that strongly associate and allow prediction of its local distribution. This represents a useful step towards developing appropriate intervention strategies to mitigate intestinal schistosomiasis transmission.Additional authors: Lucas J. Cunningham, Julie-Anne Akiko Tangena & J. Russell Stothar

Rifaximin Reduces Markers of Inflammation and Bacterial 16S rRNA in Zambian Adults with Hepatosplenic Schistosomiasis: A Randomized Control Trial

We thank the Wellcome Trust through the Southern Africa Consortium for Research Excellence for funding this study (WT087537MA)

Seroprevalence of Co-Infection of HSV-2 and HIV in Clients attending VCT at The University Teaching Hospital

The main objectives of this study are to explore the seroprevalence of co-infection of Human immunodeficiency virus and Herpes Simplex Virus-2 in clients attending voluntary counselling and testing (VCT), seroprevalence of HSV-2 among HIV negative and HIV positive and to determine associations between demographic and sexual behaviour factors on one hand and co-infection on the other.This was a descriptive study that was conducted at University Teaching Hospital in clinic 3. This clinic is a Sexually Transmitted Infections clinic which also has VCT services. The study was conducted on clients who were attending VCT for a period of three months.Clients attending VCT were asked to complete a VCT standard and a HSV-2 questionnaires. In the HSV-2 questionnaire, clients were asked questions about demographic and sexual behavioural factors. These clients were between 18 and 49 years old. For each client who gave consent, 4 millilitres of venous blood was collected once for HIV and HSV-2 tests. For testing HIV Abbott determine was used (screening test) with a sensitivity of 100% and specificity of 99.7%. The Uni-Gold test was used for confirmatory testing with sensitivity of 100% and specificity of 100%. For HSV-2 testing, indirect ELISA IgG which has the sensitivity of 99.4% and specificity of 98% was used.Before getting results, clients were also given post test counselling. Those who were found seropositive for both or either of the two viruses were referred to clinicians for management.The co-infection rate among clients attending VCT was 17.9% (41/229). The seroprevaence of HSV-2 among HIV positive clients was 59.4% (41/69) compared to seroprevalence of HSV-2 among those who were HIV negative of 13.7% (22/160). The sex distribution was significantly different between males and females (p = 0.029). Females were more likely to be co-infected than males. No age difference was observed between the two age groups those aged 18 to 34 and those between 35 and 49 years old. There was association between condom use and the co-infection (X^ 11.00; p value 0.004), while multiple sex partners yielded no significant association (p= 0.234). Those clients who reported with history of sexually transmitted infections were more likely to be co-infected than those who reported no history of sexually transmitted infections. The level of education showed no significant association with co-infection. Condom use, history of sexually transmitted infections and sex were all statistically significantly associated with co-infection. Those clients who reported non condom use, history of STIs and females were more likely to be co-infected. There was no significant different between educational level and co-infection as well as multiple sex partners and co-infection in this study.According to our results, we need to screen for HSV-2 in clients attending VCT because HSV-2 is also common in these clients. We also need counselling for both HIV and HSV-2 due to the fact that there is likehood of co-infection. There is need for more health promotion about condom use to prevent infection as reported elsewhere to reduce both HIV and HSV-2 infections. More research needs to be done in order to get more information on the screening for HSV-2 in VCT centres

Predicting COVID-19 mortality in Zambia - an Application of Machine Learning

Background: The Corona virus, has caused havoc all over the world, it has left no country untouched resulting in millions of cases and deaths. In an effort to fight back, scientist and public health professionals have used every form of advancing technology to curb the spread, predict the unforeseen adverse events, improve preparedness, and bring the world under control once more. Objective: The objective of this study was to predict mortality in hospitalized COVID-19 patients in Zambia using ML methods from a number of predictors that have been shown to be predictive of mortality. Methods: This research used powerful ML models in predicting COVID-19 mortality in 1,433 hospitalized patients in Zambia. The feature importance analysis helped in identification of important factors. The ML models GB, RF, SVM, DT, LR, and NB were used the performance metrics checked for each model were accuracy, recall, specificity, precision, F1 Score, ROC-AUC, and PRC-AUC. Results: The feature importance analysis found that hospital length of stay (LOS) and white blood cell count were the most influential features, other factors arranged in order of reducing importance included: age, wave, diabetes, hypertension, and sex. The GB achieved accuracy of 91.5%, recall of 93.6%, F1 Score of 91.7%, and ROC-AUC of 96.9%. The RF achieved accuracy of 90.9%, recall of 93.8%, F1 Score of 91.2%, and ROC-AUC of 96.8%. The SVM achieved accuracy of 87.8%, recall of 91.2%, F1 Score of 88.2%, and ROC-AUC of 94.1%. The accuracy and ROC-AUC of other models were 88.2% and 90.7% respectively for DT, 81.9% and 90.1% respectively for LR, and 79.2% and 86.9% respectively for NB. Conclusion: The study successfully derived and validated multiple ML models that predicted mortality effectively with reasonably high performance in stated metrics. The GB was the best suited for the data in our study. GB was thus recommended for similar studies with RF as best alternative. Knowledge of underlying health conditions about patients (length of hospitalization (LOS), white blood cell count, age, sex, hypertension, diabetes, and other factors) can help healthcare providers offer lifesaving services on time, improve preparedness and decongest health facilities