Mammarenaviruses of rodents, South Africa and Zimbabwe

We conducted a survey for group-specific indirect immunofluorescence antibody to mammarenaviruses by using Lassa fever and Mopeia virus antigens on serum specimens of 5,363 rodents of 33 species collected in South Africa and Zimbabwe during 1964–1994. Rodents were collected for unrelated purposes or for this study and stored at −70°C. We found antibody to be widely distributed in the 2 countries; antibody was detected in serum specimens of 1.2%–31.8% of 14 species of myomorph rodents, whereas 19 mammarenavirus isolates were obtained from serum specimens and viscera of 4 seropositive species. Phylogenetic analysis on the basis of partial nucleoprotein sequences indicates that 14 isolates from Mastomys natalensis, the Natal multimammate mouse, were Mopeia virus, whereas Merino Walk virus was characterized as a novel virus in a separate study. The remaining 4 isolates from 3 rodent species potentially constitute novel viruses pending full characterization.http://www.cdc.gov/eidam2022Medical VirologyMicrobiology and Plant PathologyUP Centre for Sustainable Malaria Control (UP CSMC)Veterinary Tropical Disease

Serum resistance and lipopolysaccharide of haemophilus ducreyi

A dissertation submitted to the Faculty of Medicine, University of the VVitwatersrand, Johannesburg, in fulfilment of the requirements for the degree Master of Science. 1990The pathogenesis of Haemophilus ducreyi, the aetiological agent of chancroid' is poorly understood. An ability to resist killing by pooled normal human serum (PNHS) appears to contribute to the virulence of several Gram-negative bacteria, influenced by their lipopolysaccharide (LPS) in certain cases. The aim of this investigation is to measure the degree of serum resistance in clinical strains of H. ducreyi, and to determine whether their LPS plays a role in this serum resistance.IT201

Diversity and biotechnology applications of thermophilic bacteria from hot-spring water in Limpopo South Africa relating to wastewater bioremediation and water safety

D.Tech. (Biotechnology)Abstract: Hot-spring environments are valuable resources for novel and useful bacteria in biotechnology. In South Africa, hot springs in Limpopo Province have been investigated by metagenomics but not by culture-based methods. This study was performed in order to describe the diversity of cultured bacteria from hot springs, and to comment on their relevance to public health and antibiotic resistance. Furthermore, potential bacterial candidates were screened for characteristics associated with wastewater (WW) bioremediation and applications. Cultured bacteria were identified by a combination of tools using the 16S rDNA sequence by comparison with public databases, percent guanine-cytosine content, amplified rDNA restriction analysis (ARDRA) and phylogeny. Resistance against ten antibiotics (carbenicillin, gentamicin, kanamycin, streptomycin, tetracycline, chloramphenicol, ceftriaxone, co-trimoxazole, nalidixic acid and norfloxacin) and eight heavy metal ions (Al, Cr, Cu, Fe, Hg, Mn, Ni and Pb) were tested using disk diffusion assays. Isolates were screened for production of enzymes and biophysical characteristics (bioflocculant and biosurfactant activities, biosorption, bioassimilation, anti-biofilm and antimicrobial properties) and selected cell free culture supernatants (CFCS) were processed by tandem LC-MS for identification of the bioactive molecules. CFCS were exposed to pollutants (pigmented food, textile dyes, polyaromatic hydrocarbons) and food WW samples to establish whether there was a reduction in turbidity or phenol levels. Forty-three (43) Gram-positive isolates were of the phylum Firmicutes with the majority of the genus Bacillus (n = 31). Different species were identified as Anoxybacillus flavithermus, Anoxybacillus rupiensis, Bacillus subtilis, Bacillus licheniformis and Brevibacillus spp. Single isolates of Gram-positive Kocuria sp. and Arthrobacter sp., and Gram-negative Cupriavidus sp., Ralstonia sp., Cronobacter sp., Tepidimonas sp., Hafnia sp. and Sphingomonas sp. were identified, previously reported to be emerging opportunistic pathogens, and an absence of Legionella sp. was reported. Low levels of antibiotic resistance (AR) were reported. Only 2.5% (n = 40) of the isolates were multiple antibiotic resistant against >3 antibiotics, while 37.5% were found for both resistance against one or two antibiotics. Resistance was found against ceftriaxone (52.5%), nalidixic acid (37.5%) and carbenicillin (22.5%). All 29 isolates tested heavy metals were tolerant to ≥2 heavy-metal salts. No association was observed between antibiotic resistance and heavy-metal tolerance. Amylase and protease positive isolates, and isolates that could discolorize bromothymol blue were detected by conventional agar plate assays. The CFCS of A. rupiensis 19S was selected for..

Phylogenetic Analysis and Antimicrobial Profiles of Cultured Emerging Opportunistic Pathogens (Phyla Actinobacteria and Proteobacteria) Identified in Hot Springs

Hot spring water may harbour emerging waterborne opportunistic pathogens that can cause infections in humans. We have investigated the diversity and antimicrobial resistance of culturable emerging and opportunistic bacterial pathogens, in water and sediment of hot springs located in Limpopo, South Africa. Aerobic bacteria were cultured and identified using 16S ribosomal DNA (rDNA) gene sequencing. The presence of Legionella spp. was investigated using real-time polymerase chain reaction. Isolates were tested for resistance to ten antibiotics representing six different classes: β-lactam (carbenicillin), aminoglycosides (gentamycin, kanamycin, streptomycin), tetracycline, amphenicols (chloramphenicol, ceftriaxone), sulphonamides (co-trimoxazole) and quinolones (nalidixic acid, norfloxacin). Gram-positive Kocuria sp. and Arthrobacter sp. and gram-negative Cupriavidus sp., Ralstonia sp., Cronobacter sp., Tepidimonas sp., Hafnia sp. and Sphingomonas sp. were isolated, all recognised as emerging food-borne pathogens. Legionella spp. was not detected throughout the study. Isolates of Kocuria, Arthrobacter and Hafnia and an unknown species of the class Gammaproteobacteria were resistant to two antibiotics in different combinations of carbenicillin, ceftriaxone, nalidixic acid and chloramphenicol. Cronobacter sp. was sensitive to all ten antibiotics. This study suggests that hot springs are potential reservoirs for emerging opportunistic pathogens, including multiple antibiotic resistant strains, and highlights the presence of unknown populations of emerging and potential waterborne opportunistic pathogens in the environment

Preferred learning modalities and practice for critical skills: A global survey of paediatric emergency medicine clinicians

© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ. Objective To describe senior paediatric emergency clinician perspectives on the optimal frequency of and preferred modalities for practising critical paediatric procedures. Methods Multicentre multicountry cross-sectional survey of senior paediatric emergency clinicians working in 96 EDs affiliated with the Pediatric Emergency Research Network. Results 1332/2446 (54%) clinicians provided information on suggested frequency of practice and preferred learning modalities for 18 critical procedures. Yearly practice was recommended for six procedures (bag valve mask ventilation, cardiopulmonary resuscitation (CPR), endotracheal intubation, laryngeal mask airway insertion, defibrillation/direct current (DC) cardioversion and intraosseous needle insertion) by at least 80% of respondents. 16 procedures were recommended for yearly practice by at least 50% of respondents. Two procedures (venous cutdown and ED thoracotomy) had yearly practice recommended b