Dr Justine Gibson

Senior Lecturer

School of Veterinary Science
Faculty of Science
gibson.j@uq.edu.au
+61 7 54601 830

Overview

Dr Gibson graduated with a Bachelor of Veterinary Science in 1996 and after working in veterinary practice for a number of years undertook a PhD investigating the epidemiology and basis of fluoroquinolone resistance in multidrug-resistant Escherichia coli and Enterobacter spp. isolated from companion animals. Dr Gibson’s research spans the fields of veterinary microbiology and molecular biology.

Dr Justine Gibson is a veterinary microbiologist with ten years’ experience researching zoonotic and animal bacterial diseases, focusing on population genetics, molecular epidemiology, microbial pathogenesis and antimicrobial resistance. She was awarded her PhD “Epidemiology and basis of fluoroquinolone resistance in multidrug-resistant Escherichia coli and Enterobacter spp. isolated from companion animals” in 2010. She was awarded a Dean’s commendation for outstanding achievement for her PhD thesis (given to the top 10% of UQ PhD theses awarded in a given calendar year). She commenced her current appointment as Lecturer in Veterinary Bacteriology and Mycology at the School of Veterinary Science, at The University of Queensland in 2010. Since then she has supervised two honours students to completion and currently supervises two PhD students, two MPhil candidates and one Masters by coursework student. Her current research interest include antimicrobial resistance with a focus on multidrug-resistant Escherichia coli and Enterobacter spp. isolated from production and companion animals, the development of novel therapies for MDR infections; infectious diseases of wildlife; bovine and porcine respiratory disease and bovine mastitis.

Research Interests

  • Studies on avian pathogenic Escherichia coli in commercial broiler chickens in Southeast Queensland.
    Avian colibacillosis has received considerable attention worldwide in the poultry industry due to its direct association with significant economic losses. Economic losses are a result of reduced production due to high mortality and morbidity. Avian Pathogenic E. coli (APEC) is the causative agent of avian colibacillosis and is capable of causing localised or systematic extraintestinal infections. The mechanism by which APEC causes disease is not yet fully understood. Recent overseas studies have sought to define the APEC pathotype and have indicated that the prevalence of various virulence genes among isolates from chickens with colibacillosis were useful markers for the detection and characterisation of APEC. In Australia, the review of the literature shows that up to date knowledge regarding the molecular and general epidemiology of APEC in poultry is very limited. My research aims to estimate the bird and farm-level prevalence, describe farm-level risk factors and describe the molecular epidemiology of APEC in clinically healthy commercial broiler chickens from South-East Queensland (SEQ). This research will produce the first in-depth understanding of the range of virulence genes present in E. coli circulating in commercial broiler chicken flocks. On the basis of this knowledge a secondary aim is to assess the likelihood of these avian E. coli being linked to human disease.
  • Antimicrobial resistance in bacteria associated with porcine respiratory disease in Australia
    Actinobacillus pleuropneumoniae, Haemophilus parasuis, Pasteurella multocida and Bordetella bronchiseptica are the most common causative agents of porcine respiratory disease which causes significant losses to the pig industry. Antimicrobial resistance has been reported in these bacteria in other countries, however, in Australia, there is no current available data. The aim of this study is to determine the antimicrobial resistance patterns of fifty three (53) A. pleuropneumoniae, fifty two (52) H. parasuis, fifty one (51) P. multocida and eighteen (18) B. bronchiseptica cultured from Australian pigs. Antimicrobial susceptibility testing was validated for H. parasuis as there are no existing standard methods for this species. H. parasuis isolates showed resistance to ampicillin, co-trimoxazole, macrolides (erythromycin, tilmicosin and tulathromycin), penicillin and tetracycline. A. pleuropneumoniae isolates were resistant to ampicillin, erythromycin, penicillin, tetracycline and tilmicosin. Resistance to ampicillin, co-trimoxazole, erythromycin, florfenicol, penicillin and tetracycline were observed in P. multocida isolates. B. bronchiseptica isolates showed resistance to beta-lactams (ampicillin, ceftiofur and penicillin), co-trimoxazole, erythromycin, florfenicol, tetracycline and tilmicosin. This study shows that antimicrobial resistance is present in bacterial respiratory pathogens of Australian pigs.
  • The role of Mycoplasma bovis in respiratory disease of Australian feeder cattle.
    The bacterial organism Mycoplasma bovis has been found to be associated with bovine respiratory disease (BRD) in feeder cattle in the United States, but has been largely overlooked as a contributing factor to BRD in Australia. In cattle, M. bovis is associated with a multitude of clinical syndromes that are typically chronic in nature and non-responsive to antimicrobial treatments. As an effective vaccine is lacking, control methods rely on a thorough understanding of the epidemiology of M. bovis in the country and production systems concerned. This study aims to help close the gap in the literature on the epidemiology of M. bovis in the Australian beef cattle population. With a �gold standard� serological diagnostic method for the detection of M. bovis-specific antibodies unavailable, a commercial enzyme linked immunosorbent assay (ELISA) will be compared to western blot antigen-antibody profiles using serum from cattle of known antibody status to determine sensitivity and specificity estimates. This will subsequently allow estimation of the sero-prevalence of M. bovis in cattle entering feedlots and grazing cattle of similar age. It will also enable possible risk factors associated with sero-positivity and those associated with a change in serological status during the first 42 days on feed to be investigated. The information gained from this study will enhance the knowledge of the epidemiology of M. bovis in Australia and will assist in the development of targeted control measures to help reduce the economic impact of BRD and M. bovis associated disease in Australia.
  • Enterotoxigenic E. coli in Pigs
    To investigate the relationship between the presence of antimicrobial resistance genes in commensal and pathogenic E. coli isolates from pigs and on-farm antimicrobial use.
  • Naturally occurring bacteriocins; a novel therapy for the treatment of MDR E.coli urinary tract infections in dogs
    Aim: To detect, isolate and use naturally occurring bacteriocins to reduce or eliminate multiple drug resistant (MDR) Escherichia coli in the urinary tract for the treatment and management of recurrent MDR cystitis in dogs, as an alternative to the use of antibiotics. Background: Bacterial UTI are common in canines and E. coli, is the organism most frequently cultured [1, 2]. It has been estimated that 14% of all dogs that visit a veterinarian will be diagnosed with a UTI at some point in their lifetime [3]. The majority of these infections are simple and will resolve after 2-3 weeks of antimicrobial therapy. However, recently, resistance to antimicrobials has been observed in canine urinary tract isolates, in particular for fluoroquinolones, third generation cephalosporins, and clavulanic acid-potentiated β-lactams, which are all regarded as second-line veterinary antimicrobial agents [2, 4, 5] Due to the rapid rise and spread of MDR E. coli alternatives to conventional antimicrobial therapies are urgently needed. Bacteriocins provide an alternative solution. Bacteriocins, which are ubiquitous in nature, are antimicrobial peptides and proteins produced by a variety of Gram positive and Gram negative bacteria to inhibit the growth of similar or closely related bacterial strain(s) [6, 7]. Compared to traditional antimicrobial agents, bacteriocins have a relative narrow killing spectrum and can be selected to target specific bacterial pathogens, e.g. MDR E. coli [6, 7], and could potentially be used with other novel therapies like the urinary �probiotic� asymptomatic bacteriuria strain E. coli 87392 [8]. Targeting specific pathogens will reduce antimicrobial selection pressures prolonging the shelf life of current antimicrobial agents and will reduce the effects on commensal organisms resulting in decreases in hospital acquired infections [6]. It has also been anticipated that the levels of induced resistance to bacteriocins will be low [7, 9]. The increase in antimicrobial resistant pathogens is a serious threat to animal health. However with further research, bacteriocins, due to their high potency and specificity, have the potential of becoming the next generation of pharmaceuticals [7].

Qualifications

  • Graduate Certificate in Higher Education, The University of Queensland
  • Doctor of Philosophy, The University of Queensland
  • Bachelor of Veterinary Science, The University of Queensland

Publications

View all Publications

Supervision

View all Supervision

Publications

Book Chapter

  • Finch, Neil and Gibson, Justine (2015). Utilisation and exploitation. In Athol Klieve, Lindsay Hogan, Stephen Johnston and Peter Murray (Ed.), Marsupials and monotremes: nature's enigmatic mammals (pp. 379-395) New York, NY, United States: Nova Science.

Journal Article

Conference Publication

Other Outputs

Grants (Administered at UQ)

PhD and MPhil Supervision

Current Supervision