A5004821284- Pneumonia and Respiratory Infections
- Pneumocystis jirovecii pneumonia detection and treatment
- Respiratory viral infections research
- Antibiotic Resistance in Bacteria
- Tuberculosis Research and Epidemiology
- Escherichia coli research studies
- Viral gastroenteritis research and epidemiology
- HIV/AIDS drug development and treatment
- Salmonella and Campylobacter epidemiology
- Burkholderia infections and melioidosis
- HIV/AIDS Research and Interventions
- Streptococcal Infections and Treatments
- Pharmaceutical and Antibiotic Environmental Impacts
- Fungal Infections and Studies
- Zoonotic diseases and public health
- Listeria monocytogenes in Food Safety
- Clostridium difficile and Clostridium perfringens research
- Mycobacterium research and diagnosis
- Chemical Looping and Thermochemical Processes
- Pediatric health and respiratory diseases
- Bacteriophages and microbial interactions
- Antifungal resistance and susceptibility
- Emergency and Acute Care Studies
- Bacterial biofilms and quorum sensing
- Infective Endocarditis Diagnosis and Management
Stellenbosch University
2004-2024
Henry M. Jackson Foundation
2022
University of Cape Town
2015-2021
National Health Laboratory Service
2019
St. John's University
2013
Mayo Clinic in Arizona
2010
Tygerberg Hospital
2010
Mayo Clinic
2008
The emergence of extended-spectrum beta-lactamase (ESBL) and plasmid-mediated AmpC (pAmpC) enzymes in Escherichia coli raises concern regarding accurate laboratory detection interpretation susceptibility testing results. Twenty-six cefpodoxime ESBL screen-positive, cefoxitin-resistant E. clinical isolates were subjected to clavulanate confirmatory employing disk augmentation, Etest, the BD Phoenix NMC/ID-132 panel. Phenotypic pAmpC production was assessed by boronic acid augmentation. genes...
Monitoring changes in pneumococcal carriage is key to understanding vaccination-induced shifts the ecology of and impact on health. We longitudinally investigated dynamics infants. Pneumococcal isolates were obtained from nasopharyngeal (NP) swabs collected 2-weekly 137 infants enrolled birth through their first year life. Pneumococci serotyped by sequetyping, confirmed Quellung. isolated 54% (1809/3331) Median time acquisition was 63 days. Serotype-specific rates ranged 0.01 0.88...
Fungal prosthetic valve endocarditis is a rare but devastating disease. To better characterise this syndrome, we retrospectively reviewed 21 cases of fungal seen at Mayo Clinic over the past 40 years. The average patient age was 65 years with 2 : 1 male predominance. Twelve (57%) occurred within year placement. aortic most commonly affected, and common aetiological agent Candida species, followed by Histoplasma capsulatum. Although 20 patients (95%) were immunocompetent, they had other risk...
Abstract We report emergence of ciprofloxacin-resistant Salmonella enterica serovar Kentucky in Canada during 2003–2009. All isolates had similar macrorestriction patterns and were multilocus sequence type ST198, which has been observed Europe Africa. Ciprofloxacin-resistant S. represents 66% all nontyphoidal sp. since 2003.
Over the last decade, a marked increase in Salmonella enterica serotype 4,[5],12:i:- with core resistance to ampicillin, streptomycin, sulphonamides and tetracycline (ASSuT) has been observed Europe. This study describes emergence characterization of isolates multidrug-resistant Canada.Human clinical were identified by provincial laboratories from 2003 2010. Serotyping phage typing performed standardized methodologies. MIC values determined using broth microdilution. PCR was used determine...
The acquisition of beta-lactamases in members the Enterobacteriaceae family poses a challenge to antimicrobial susceptibility testing clinical laboratory. We correlated distribution MICs for Klebsiella spp. and Escherichia coli with presence extended-spectrum beta-lactamase (ESBL) plasmid-mediated AmpC (pAmpC) genes. A total 264 isolates were subjected cefazolin, ceftriaxone, cefotaxime, ceftazidime, cefepime, aztreonam agar dilution MIC determination; ESBL screening confirmatory by methods...
Abstract Background In light of rampant childhood diarrhoea, this study investigated bacterial pathogens from human and non-human sources in an urban informal settlement. Meat abattoirs ( n = 85), river water 64), diarrheic stool 66) were collected between September 2015 May 2016. A duplex real-time PCR, gel-based CHROMagar™STEC used to screen Tryptic Soy Broth (TSB) for E. coli . Standard methods other selected food waterborne pathogens. Results Pathogens isolated stool, meat, surface...
Lower respiratory tract infection in children is increasingly thought to be polymicrobial origin. Children with symptoms suggestive of pulmonary tuberculosis (PTB) may have tuberculosis, other infections or co-infection Mycobacterium and pathogens. We aimed identify the presence potential pathogens nasopharyngeal (NP) samples from suspected PTB. NP collected consecutive presenting PTB at Red Cross Children’s Hospital (Cape Town, South Africa) were tested by multiplex real-time RT-PCR....
ABSTRACT Sequence analysis of Pneumocystis jiroveci internal transcribed spacer (ITS) regions has become an important epidemiological tool. The objectives the present study were to investigate sequence variations in ITS1-5.8S ribosomal DNA (rDNA)-ITS2 regions; determine P. genotypes Cape Town, South Africa; and resolve lineage evolution types by use coalescent theory. ITS amplified from samples collected 19 patients. PCR products cloned, four five clones sequenced each specimen. Statistical...
Nasopharyngeal (NP) colonization by Streptococcus pneumoniae (pneumococcus) precedes the development of respiratory tract infection. Colonization antimicrobial-resistant pneumococci, especially in infants, is a major public health concern. We longitudinally investigated antimicrobial-resistance amongst pneumococci colonizing nasopharynx South African infants immunized with 13-valent pneumococcal conjugate vaccine (PCV13). NP swabs were collected every second week from birth through first...
ABSTRACT Dihydropteroate synthase (DHPS) gene mutations have raised concerns about emerging sulfonamide resistance in Pneumocystis jirovecii . DHPS and dihydrofolate reductase (DHFR) products were amplified clinical specimens from South African patients. One of 53 genes sequenced contained the double mutation Thr55Ala Pro57Ser. DHFR detected Ala67Val new Arg59Gly C278T.
Pneumococcal serotype identification is essential to monitor pneumococcal vaccine effectiveness and replacement. Serotyping by conventional serological methods are costly, labour-intensive, require significant technical expertise. We compared two different molecular pneumococci isolated from the nasopharynx of South African infants participating in a birth cohort study, Drakenstein Child Health Study, an area with high 13-valent conjugate (PCV13) coverage.A real-time multiplex PCR (rmPCR)...
We present the first confirmation of presence B. pseudomallei in environment Ghana. This study will bring attention to a disease with potential cause significant morbidity and mortality Ghana, but which has gone completely unrecognized until this point.
Background S. aureus colonization is a risk factor for invasive disease. Few studies have used strain genotype data to study acquisition and carriage patterns. We investigated nasopharyngeal in infants an intensively sampled South African birth cohort. Methods Nasopharyngeal swabs were collected at fortnightly from 137 through their first year of life. was characterized by spa typing. The incidence acquisition, median duration each determined. patterns defined combining the carrier index...
Introduction: Shiga toxin-producing Escherichia coli (STEC) is an emerging infectious pathogen which could lead to haemolytic uremic syndrome. Even though previous studies have compared the performance of CHROMagarTMSTEC real-time polymerase chain reaction (PCR) in Europe, no study has been done assess its on African isolates.Objectives: This project aimed validate and test in-house-developed duplex PCR use it as a reference standard determine isolates from diarrhoeic stool samples.Methods:...
Melioidosis is a potentially severe disease caused by the gram-negative soil-dwelling bacterium called Burkholderia pseudomallei . The true breadth of distribution this tropical pathogen starting to emerge with environmental and clinical isolates frequently characterized in new countries regions. Even so, isolates, cases, genetic data from continent Africa remain scant. We previously confirmed presence B. environment Ghana, unmasking area endemicity for pathogen. Here, we describe...
The use of positive blood culture bottles for direct disk diffusion susceptibility testing (dDD), together with chromogenic limited to groups pathogens antimicrobial interpretation may provide a means laboratories-in-development introduce rapid abbreviated testing. We assessed the performance dDD on Chromatic MH agar using contrived and compared findings current standard practice. Furthermore, we characterized growth 24 bacterial 3 yeast species aid spot tests same-day identification....
Background: Diarrhoea is a major cause of morbidity in Cape Town, South Africa, and mortality attributed to failure recognize the severity condition. Cryptosporidium Giardia are increasingly recognized as important causes diarrhoea Africa however, suboptimal diagnostic techniques may lead underappreciation their significance. Our objectives compare yield direct immunofluorescent antigen (DFA) microscopy on concentrated stool samples for Giardia, with current approach wet mount auramine...