Epidemiology and multilocus sequence typing of group B streptococcus colonising pregnant women and their neonates at Dr George Mukhari Academic Hospital, Pretoria

Background: Group B streptococcus (GBS) is regarded as one of the most important causes of maternal and neonatal morbidity and mortality in many parts of the world. GBS recto-vaginal colonization is important in the health of a mother and her neonate, especially in developing countries. Maternal vaginal colonization with GBS at the time of delivery can cause vertical transmission to the neonate. Multilocus sequence typing (MLST) is a technique used to characterize microbial isolates by means of sequencing internal fragments of housekeeping genes and has the advantage of reproducibility and has been shown to correlate with the other typing techniques and thus has emerged as the standard for delineating the clonal population of GBS. The study aimed to investigate the epidemiology of GBS colonization among pregnant women and their neonates, and to characterize the isolates by multilocus sequence typing technique at Dr George Mukhari Academic Hospital, Pretoria. Methodology: A total of 413 pregnant women who visited the antenatal clinic were recruited and screened. Participants were interviewed using a questionnaire to gather demographic and other relevant information such as history of current pregnancy, previous miscarriages and still births. Samples from maternal rectum and vagina as well as neonate ear and umbilical cord were taken for culture using colistin and nalidixic acid (CNA) blood agar and incubated for 24-48 hours. If negative after 48 hours, Todd-Hewitt broth was subcultured after 18-48 hours onto sheep blood agar. Multilocus sequence typing (MLST) was used to characterize seven group B streptococcus isolates collected at Dr George Mukhari academic hospital. Fragments of seven housekeeping genes were amplified by polymerase chain reaction (PCR) for each strain and sequenced. CLC bio software (Inqaba biotech, South Africa; Pretoria) was used to analyse sequenced loci and UPGMA dendrogram was constructed. Results: The colonization rate for GBS in pregnant women and their neonates was 30.9% and 0%, respectively. A higher proportion of GBS were isolated from the rectum (37.9%) as compared to the vagina (20.6%). Most socio-economic, demographic and obstetric factors analysed were not significantly associated with.GBS colonization. On 128 positive samples, the results of Todd-Hewitt enrichment broth and direct plating method using CNA were compared. A total of 45.3% of colonised were positive on direct selective agar (CNA); an additional 54.7% samples were recovered from Todd-Hewitt broth. Three genes (adhP, glnA and tkt) were sequenced successfully for six samples (1, 2. 4,6,12 and 65). The UPGMA tree with 1000 bootstrap showing the relationship between six samples was drawn.Conclusion: This study revealed that pregnant women of all ages are at risk of group B streptococcus colonization. Group B streptococcus was common among pregnant women at Dr George Mukhari Academic Hospital. No socio-economic risk factor was associated with group B streptococcus colonization. Results confirm that the combination of Todd-Hewitt broth and CNA agar plate is a time saving and sensitive method. The allelic profile, characteristics such as G+C (guanine+cytosine) content and dN/dS ratio were not analysed because of the smaller sample size used in this study, which shows that the MLST method was unsuccessful in this study. The UPGMA tree based on differences in consensus of the isolates showed that all group B streptococcus isolates are clustered and descend from a single node.Life SciencesM.Sc. (Life Sciences

Storage Potential of the Cactus Pear (Opuntia ficus-indica) Fruit Juice and Its Biological and Chemical Evaluation during Fermentation into Cactus Pear Wine

The cactus pear (Opuntia ficus-indica) fruit is widely cultivated and grown naturally in arid regions because it is adaptive to a wide range of soil and environments. The pear fruit is inhabited by different micro-organisms and has chemical composition suitable for wine making. Profiling the contributing micro-organisms and evaluating the chemical parameters of cactus pear wine can assist in selecting reliable microbes for use as starter cultures. Spontaneous fermentation was carried out for 13 days and followed by three months of cold storage. Fermenting microbes were isolated, characterised and identified. The chemical parameters, namely, sugar concentration, ethanol concentration, pH and total acidity, were analysed. A total of 22 micro-organisms were identified, among which nine yeast species, two acetic acid bacteria (Gluconobacter spp.) and eight Bacillus spp. were isolated. The simple sugars were used up, and ethanol was produced to a high concentration of 50.9 g/L. The pH ranged between 2.8 and 2.9; hence, a maximum total acidity of ±25 g/100 mL was achieved. At least 78% of the available tannins were used in the early stages of fermentation. Potassium and magnesium were the highest minerals obtained, and zinc was the lowest. The highest ash content obtained was 7.9 g/100 mL. The vitamin C content was retained and gradually increased throughout the fermentation process. The findings indicate that lasting flavoured wine can be developed from cactus pear fruit because of the fermenting microbes and the chemical composition of the fruit

Bacterial pathogens identified from houseflies in different human and animal settings : a systematic review and meta‐analysis.

Housefly (Musca domestica) is an excellent candidate for the distribution of susceptible and resistant bacterial strains that potentially threaten public health. To date, there is a paucity of information on the global distribution of pathogenic bacteria of medical and veterinary importance from diverse environmental settings. Therefore, this study was undertaken to conduct a systemic review and meta-analysis to estimate occurrence of various bacterial species of medical and veterinary importance harboured by houseflies around the world. Published articles from 1980 to 2020 were retrieved from electronic databases and assessed for eligibility according to Preferred Reporting Items for Systemic Reviews and Meta-Analysis guidelines. Seventy-eight studies were included in the review with only 44 studies being eligible for meta-analysis. Results indicated that eligible studies used in this review were from four continents, i.e., Asia (47.4%) America (23.1%), Africa (20.5%) and Europe (8.9%). The majority of the studies (56.4%) used the culture method for the identification of bacterial pathogens, while 30.7% used both culture and PCR techniques. For meta-analysis, we focused on five pathogenic bacterial species including Escherichia coli, Enterococcus faecium, Klebsiella pneumoniae, Pseudomonas aeruginosa and Staphylococcus aureus. High heterogeneity was found among studies investigating different pathogens including E. coli (Q = 10,739.55; I2 = 99.60; Q-p 0.0001), E. faecium (Q = 317.61; I2 = 86.46; Q-p < 0.0001), K. pneumonia (Q = 1,576.61; I2 = 97.27; Q-p < 0.0001), S. aureus (Q = 2,439.12; I2 = 98.24; Q-p < 0.0001) and P. aeruginosa (Q = 1,283.0; I2 = 96.65; Q-p < 0.0001). Furthermore, it was observed that houseflies carried a considerable number of susceptible and antibiotic-resistant bacterial strains that pose considerable threats to public health. Findings from this study have provided more insight on the vectoral potential of houseflies in the transmission of significant bacterial pathogens from different regions across the world. Further investigation is required to quantify the bacterial contamination and dissemination by houseflies

“One Health” perspective on prevalence of co-existing extended-spectrum β-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae: a comprehensive systematic review and meta-analysis

Abstract Background The Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) bacterial isolates that produce extended-spectrum β-lactamases (ESBLs) contribute to global life-threatening infections. This study conducted a systematic review and meta-analysis on the global prevalence of ESBLs in co-existing E. coli and K. pneumoniae isolated from humans, animals and the environment. Methods The systematic review protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) [ID no: CRD42023394360]. This study was carried out following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. One hundred and twenty-six eligible studies published on co-existing antibiotic resistance in E. coli and K. pneumoniae between 1990 and 2022 were included. Results The pooled prevalence of ESBL-producing E. coli and K. pneumoniae was 33.0% and 32.7% for humans, 33.5% and 19.4% for animals, 56.9% and 24.2% for environment, 26.8% and 6.7% for animals/environment, respectively. Furthermore, the three types of resistance genes that encode ESBLs, namely blaSHVblaCTX−M,blaOXA, and blaTEM, were all detected in humans, animals and the environment. Conclusions The concept of “One-Health” surveillance is critical to tracking the source of antimicrobial resistance and preventing its spread. The emerging state and national surveillance systems should include bacteria containing ESBLs. A well-planned, -implemented, and -researched alternative treatment for antimicrobial drug resistance needs to be formulated

Prevalence and antimicrobial resistance profiles of Campylobacter species in South Africa: a “One Health” approach using systematic review and meta-analysis

Objectives: This study investigated the prevalence and antibiotic resistance (AR) profiles of Campylobacter spp. isolated from animals, humans, and the environment in South Africa based on available published data. Methods: Original articles published from January 1, 1990 to January 1, 2021 were searched from PubMed, ScienceDirect, Google Scholar, Africa Index Medicus, Scopus, and African Journal Online databases. Data were analyzed with Comprehensive Meta-Analysis (version 3.0). Results: After screening, articles on animals (n = 25), humans (n = 7), environment (n = 3), animals/environment (n = 2), and a (n = 1) study on animals, humans, and the environment were included in this review. The pooled prevalence estimates (PPEs) were 28.8%, 16.4%, and 28.4% in animals, humans, and the environment, respectively. The Campylobacter jejuni and Campylobacter coli species were commonly isolated from humans, animals, and the environment in South Africa. The AR profiles were screened from 2032 Campylobacter spp., with the highest PPE of AR observed against clindamycin (76.9%) and clarithromycin (76.5%). Campylobacter isolates tested with the disk diffusion assay and minimum inhibitory concentration methods recorded an overall AR prevalence of 35.3% and 37.1%, respectively, whereas multidrug resistance PPE was 35.3%. Conclusion: Regular surveillance of Campylobacter spp. prevalence and its antimicrobial resistance strains is recommended, as well as the formulation of a “One Health” approach for better management and control of Campylobacter spp. infection in South Africa