Spatial Distribution of Diarrhoea and Microbial Quality of Domestic Water during an Outbreak of Diarrhoea in the Tshikuwi Community in Venda, South Africa

Total microbial quality assessment and geographical information system were used for evaluating the quality of water and the spatial distribution of diarrhoea cases in Tshikuwi, a rural community in South Africa, during an outbreak of diarrhoea. The water-abstraction points included two groundwater storage tanks, namely Tank 1 and Tank 2 and the Khandanama river. Indicator microbial counts for total coliforms, faecal coliforms, enterococci, and heterotrophic bacteria exceeded the limit for no risk as stipulated by the South African water-quality guidelines for domestic use for Tank 1 and the Khandanama river. Vibrio, Salmonella, and Shigella species were prevalent in the Khandanama river. The spatial distribution of diarrhoea cases showed a hot-spot of diarrhoea cases close to Tank 1 and the Khandanama river. Results of chi-square analysis showed that the proportion of infection from each water source was different or that infection depends on the type of water source (α=0.05). The demonstrated spatial clustering of diarrhoea cases might have been influenced by the poor microbial quality of water used from Tank 1 and the Khandanama river. The results further highlight the urgent need of water-treatment facilities and monitoring of water quality in rural communities of South Africa

Hepatitis B virus in HIV-infected patients in north-eastern South Africa: Prevalence, exposure, protection and response to HAART

Objective. Hepatitis B virus (HBV) and HIV are endemic infections in many African countries. The objectives of this study were to determine the levels of exposure to, and protection from, HBV, as well as the prevalence of HIVHBV co-infection and the response of HBV to highly active anti-retroviral therapy (HAART) in a cross-section of HIV-infected patients in north-eastern South Africa. Study design. This was a laboratory-based, unmatched study. Three hundred and eighty patients were screened by ELISA for HBsAg, anti-HBc and anti-HBs. Samples non-reactive for HBsAg but reactive for anti-HBc were examined for occult HBV infection. Response to HAART was assessed by measuring HBV viral loads, seroconversion from HBeAg to anti-HBe, and levels of aminotransferase. Results. Of the study population of 380, 60% (95% CI 54.8 - 64.9) were exposed to HBV based on HBsAg, anti-HBs or anti-HBc; 20% (95% CI 16.1 - 24.4) had active HBV infection, based on HBsAg serology, and 30% (95% CI 25.2 - 35.2) were protected, based on anti-HBs levels ≥10 IU/l. Of 181 HBsAg-negative individuals, 61 had HBV occult infection (33.7%, 95% CI 26.9 - 41.1). The differences in prevalence were not statistically significant when gender, marital status and CD4+ cell counts were considered. Of 21 patients analysed, 80% showed adequate response to the first-line HAART regimen (stavudine/lamivudine/efavirenz or nevirapine) after 12 months of use. Conclusion. The study confirms the higher level (60%) of exposure to HBV in HIV patients in Limpopo Province, as well as the high (20%) prevalence of HBsAg positivity and occult hepatitis B (33.7%). However, further studies are warranted to corroborate the benefit of lamivudine-containing HAART regimens, as HIV/HBV co-infected patients have a higher liver-related mortality if hepatitis B is not treated

Further screening of Venda medicinal plants for activity against HIV type 1 reverse transcriptase and integrase

The use of medicinal plants for AIDS-related conditions is common in South Africa. In order to establish an antiviral rationale for the use of these plants we screened fractions of the methanol extracts of medicinal plants for activity against HIV-1 reverse transcriptase (RT) and integrase (IN). The n-butanol fraction obtained from the crude methanol extracts of the roots of Bridelia micrantha (Hochst) Baill. (Euphorbiaceae) was observed to be as the most active inhibiting the RNA-dependent-DNA polymerization (RDDP) activity of HIV-1 RT with an IC50 of 7.3 g/ml. However, it had no activity on the 3’-end processing activity of HIV integrase. Bioassay-guided fractionation of the n-butanol fraction yielded friedelin and -sistosterol, which did not inhibit the RDDP of RT or 3’-end processing functions of IN even at a concentration of 500 M. An uncharacterized fraction obtained in the bioassay-guided fractionating process inhibited the RDDP with an IC50 of 9.6 g/ml, but had no inhibition on IN. Phytochemical screening indicated the presence of flavonoids and tannins in the uncharacterized fraction.Key words: HIV-1; reverse transcriptase; integrase; medicinal plants; inhibition; Venda; South Afric

PHENOLIC CONTENT DISTRIBUTION AND ANTIOXIDANT ACTIVITIES OF TERMINALIA SERICEA BURCH

Background: Terminalia sericea has been used traditionally for the treatment of diseases associated with oxidative stress. This study was aimed at determining the distribution of phenols in the leaves, stem bark and root bark of Terminalia sericea and their antioxidant activity. Materials and methods: Hot and cold water, methanol/acetone extracts were evaluated for their total phenolic content (TPC), flavone/flavonol content (FFC), flavonone/dihydroflavone content (FDFC), hydroxycinnamic acid derivative content (HCAC) and tannin content (TC). DPPH (2,2-diphenyl-1-picrylhydrazyl) free radicals and reducing power assays were used to assess the antioxidant activity. Results: The leaves had the highest average TPC (440) expressed in milligram Gallic Acid Equivalent (mgCAE) /gram of the extract. The leaves also had the highest average TC (7.14) expressed in milligram Quercetin Equivalent (mgQE) /gram of the extract. The stem had the highest average FDFC (19.23 mgQE/g) while the root had the highest average FFC (74.76 mgQE/g) and HCAC (214.57) expressed in milligram Caffeic Acid Equivalent mgCAE/ gram of the extract. The stem exhibited the highest average DPPH free radical scavenging (9.85 µg/mL) and reducing power (6.01 µg/mL) activities. Water was a better extracting solvent for TPC and FDFC while methanol/acetone was a better extracting solvent for FFC and HCAC. The correlation between TC and reducing power activity (r=0.668) at P < 0.05 suggests that tannins were responsible for the antioxidant activity. Conclusion: This study has shown that the distribution of phenolics differs in the organs of T. sericea, and could affect the quality of medicinal products sold

Introducing a drift and diffusion framework for childhood growth research

Acknowledgements We thank the participants and staff of the MAL-ED study for their vital contributions and we thank Prof. Laura Caulfield for her insightful and constructive input. The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the U.S. National Institutes of Health or Department of Health and Human Services. Publisher Copyright: © 2020 Lewis FI et al.Peer reviewedPublisher PD

Psychosocial and environmental determinants of child cognitive development in rural south africa and tanzania: findings from the mal-ed cohort

Background Approximately 66% of children under the age of 5 in Sub-Saharan African countries do not reach their full cognitive potential, the highest percentage in the world. Because the majority of studies investigating child cognitive development have been conducted in high-income countries (HICs), there is limited knowledge regarding the determinants of child development in low- and middle-income countries (LMICs). Methods This analysis includes 401 mother-child dyads from the South Africa and Tanzania sites of the Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) longitudinal birth cohort study. We investigated the effect of psychosocial and environmental determinants on child cognitive development measured by the Wechsler Preschool Primary Scales of Intelligence (WPPSI) at 5 years of age using multivariable linear regression. Results Socioeconomic status was most strongly associated with child cognitive development (WPSSI Score Difference (SD):14.27, 95% CI:1.96, 26.59). Modest associations between the organization of the home environment and its opportunities for cognitive stimulation and child cognitive development were also found (SD: 3.08, 95% CI: 0.65, 5.52 and SD: 3.18, 95% CI: 0.59, 5.76, respectively). Conclusion This study shows a stronger association with child cognitive development at 5 years of age for socioeconomic status compared to more proximal measures of psychosocial and environmental determinants. A better understanding of the role of these factors is needed to inform interventions aiming to alleviate the burden of compromised cognitive development for children in LMICs.publishedVersio

PREVALENCE OF CRYPTOSPORIDIUM SPP. AMONG ASYMPTOMATIC HEALTHY EXPATRIATE WORKERS IN SHARJAH, UNITED ARAB EMIRATES

Background: Epidemiological data on Cryptosporidium infections in the United Arab Emirates (UAE) is scarce. Therefore, the main objective of this study was to determine the prevalence of Cryptosporidium species among a community of expatriates in Sharjah, UAE working in different sectors, including the food industry, house maids and other domestic occupations. Materials and Methods: One hundred and thirty four stool samples were collected from asymptomatic individuals presenting to the Sharjah Municipality Public Health Clinic (SMPHC) for screening of intestinal parasites for work permission purposes between 2009 and 2011. Demographic information such as age, sex, and country of origin was collected. Genomic DNA extracted from the stool samples were tested for Cryptosporidium species using real-time PCR (qPCR). Results: Twenty-six individuals (19.4%) were positive for Cryptosporidium sp. by PCR. The infection rate was found to be highest in Afghan nationals (33%; 3/9) compared with the rest of the study population; yet, no significant association existed between nationality and infection rate. Moreover, no association was observed between infection rate and gender (χ2 = 2.439; P = 0.118), nor infection rate and age group (χ2 = 1.219; P = 0.544). Conclusion: Infection by Cryptosporidium sp. was common in the study group, and further studies are needed within the native Emirati population before any conclusions can be made about foreigners potentially transmitting the parasite. Furthermore, data provided in this study could help determine its public and veterinary significance particularly in outbreaks in the country

Prevalence of drug-resistant mutations in newly diagnosed drug-naïve HIV-1-infected individuals in a treatment site in the Waterberg District, Limpopo province

Aim. We studied the prevalence of resistance mutations in drug-naïve HIV-infected individuals at the Bela-Bela treatment site to gather information on the presence of antiretroviral (ARV) drug-resistant viruses in drug-naïve populations, so as to improve treatment guidance. Subjects and methods. Drug-naive HIV-1-infected individuals were sequentially recruited between February 2008 and December 2008 from individuals visiting the voluntary counseling and testing (VCT) services of the Bela-Bela HIV/AIDS Wellness Clinic. Viral subtyping was done by phylogenetic analysis; drug-resistant mutations were determined according to the Stanford HIV Drug Resistance Interpretation and the International AIDS society-USA guidelines. Results. A drug-resistant mutation prevalence of 3.5% (95% confidence interval 0.019796 - 0.119077) comprising Y181C and L33F was observed; 98% of the viruses were HIV-1 subtype C on the protease (PR) and reverse transcriptase (RT) gene regions. Conclusion. The prevalence of drug-resistant mutations in drug-naïve persons may be low in Bela-Bela after 8 years of access to antiretroviral treatment (ART), and resistance testing before initiating treatment may not be needed

Bacterial Contamination of Vhuswa - A Local Weaning Food and Stored Drinking-water in Impoverished Households in the Venda Region of South Africa

Bacterial contaminants of Vhuswa, a traditional maize-based weaning food, and domestic drinking-water stored in impoverished rural households in Venda of Limpopo province, South Africa, were determined. One hundred and twenty-five samples of Vhuswa fed to children aged less than five years were assessed for Escherichia coli , Campylobacter jejuni , Salmonella , and Shigella . The microbiological quality of 125 drinking-water samples was also evaluated using total coliforms, faecal coliforms, and faecal streptococci as indicators. The frequency of isolation of E. coli, Salmonella, Shigella, and C. jejuni from the Vhuswa samples was 70%, 5%, 5%, and 2% respectively. The geometric mean counts of total coliforms, faecal coliforms, and faecal streptococci in tap-water stored in household containers ranged from 4.9x102 to 5.8x103 cfu 100 mL-1 , 2.6x102 to 3.7x103 cfu 100 mL-1 , and 3.1x103 to 5.8x103 cfu 100 mL-1 respectively, and for stored spring water it was 5.1x103 cfu 100 mL-1 , 3.2x103 cfu 100 mL-1 , and 5.1x103 cfu 100 mL-1 respectively. The frequent contamination of water and food samples in this study has important implications for the health of children from impoverished communities