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Brisbane, Australia

Thomson R.M.,Gallipoli Medical Research Center | Carter R.,Reference Pathology Laboratory | Tolson C.,Reference Pathology Laboratory | Coulter C.,Reference Pathology Laboratory | And 2 more authors.
BMC Microbiology | Year: 2013

Background: Nontuberculous mycobacteria (NTM) are normal inhabitants of a variety of environmental reservoirs including natural and municipal water. The aim of this study was to document the variety of species of NTM in potable water in Brisbane, QLD, with a specific interest in the main pathogens responsible for disease in this region and to explore factors associated with the isolation of NTM. One-litre water samples were collected from 189 routine collection sites in summer and 195 sites in winter. Samples were split, with half decontaminated with CPC 0.005%, then concentrated by filtration and cultured on 7H11 plates in MGIT tubes (winter only). Results: Mycobacteria were grown from 40.21% sites in Summer (76/189) and 82.05% sites in winter (160/195). The winter samples yielded the greatest number and variety of mycobacteria as there was a high degree of subculture overgrowth and contamination in summer. Of those samples that did yield mycobacteria in summer, the variety of species differed from those isolated in winter. The inclusion of liquid media increased the yield for some species of NTM. Species that have been documented to cause disease in humans residing in Brisbane that were also found in water include M. gordonae, M. kansasii, M. abscessus, M. chelonae, M. fortuitum complex, M. intracellulare, M. avium complex, M. flavescens, M. interjectum, M. lentiflavum, M. mucogenicum, M. simiae, M. szulgai, M. terrae. M. kansasii was frequently isolated, but M. avium and M. intracellulare (the main pathogens responsible for disease is QLD) were isolated infrequently. Distance of sampling site from treatment plant in summer was associated with isolation of NTM. Pathogenic NTM (defined as those known to cause disease in QLD) were more likely to be identified from sites with narrower diameter pipes, predominantly distribution sample points, and from sites with asbestos cement or modified PVC pipes. Conclusions: NTM responsible for human disease can be found in large urban water distribution systems in Australia. Based on our findings, additional point chlorination, maintenance of more constant pressure gradients in the system, and the utilisation of particular pipe materials should be considered. © 2013 Thomson et al.; licensee BioMed Central Ltd.

Thomson R.M.,Gallipoli Medical Research Center | Tolson C.E.,Reference Pathology Laboratory | Carter R.,Reference Pathology Laboratory | Huygens F.,Queensland University of Technology | Hargreaves M.,Queensland University of Technology
Epidemiology and Infection | Year: 2014

M. fortuitum is a rapidly growing mycobacterium associated with community-acquired and nosocomial wound, soft tissue, and pulmonary infections. It has been postulated that water has been the source of infection especially in the hospital setting. The aim of this study was to determine if municipal water may be the source of community-acquired or nosocomial infections in the Brisbane area. Between 2007 and 2009, 20 strains of M. fortuitum were recovered from municipal water and 53 patients' isolates were submitted to the reference laboratory. A wide variation in strain types was identified using repetitive element sequence-based PCR, with 13 clusters of ≥2 indistinguishable isolates, and 28 patterns consisting of individual isolates. The clusters could be grouped into seven similar groups (>95% similarity). Municipal water and clinical isolates collected during the same time period and from the same geographical area consisted of different strain types, making municipal water an unlikely source of sporadic human infection. © Cambridge University Press 2014.

Thomson R.,Gallipoli Medical Research Center | Tolson C.,Reference Pathology Laboratory | Carter R.,Reference Pathology Laboratory | Coulter C.,Reference Pathology Laboratory | And 2 more authors.
Journal of Clinical Microbiology | Year: 2013

It has been postulated that susceptible individuals may acquire infection with nontuberculous mycobacteria (NTM) from water and aerosol exposure. This study examined household water and shower aerosols of patients with NTM pulmonary disease. The mycobacteria isolated from clinical samples from 20 patients included M. avium (5 patients), M. intracellulare (12 patients), M. abscessus (7 patients), M. gordonae (1 patient), M. lentiflavum (1 patient), M. fortuitum (1 patient), M. peregrinum (1 patient), M. chelonae (1 patient), M. triplex (1 patient), and M. kansasii (1 patient). One-liter water samples and swabs were collected from all taps, and swimming pools or rainwater tanks. Shower aerosols were sampled using Andersen six-stage cascade impactors. For a subgroup of patients, real-time PCR was performed and high-resolution melt profiles were compared to those of ATCC control strains. Pathogenic mycobacteria were isolated from 19 homes. Species identified in the home matched that found in the patient in seven (35%) cases: M. abscessus (3 cases), M. avium (1 case), M. gordonae (1 case), M. lentiflavum (1 case), and M. kansasii (1 case). In an additional patient with M. abscessus infection, this species was isolated from potable water supplying her home. NTM grown from aerosols included M. abscessus (3 homes), M. gordonae (2 homes), M. kansasii (1 home), M. fortuitum complex (4 homes), M. mucogenicum (1 home), and M. wolinskyi (1 home). NTM causing human disease can be isolated from household water and aerosols. The evidence appears strongest for M. avium, M. kansasii, M. lentiflavum, and M. abscessus. Despite a predominance of disease due to M. intracellulare, we found no evidence for acquisition of infection from household water for this species. Copyright © 2013, American Society for Microbiology. All Rights Reserved.

Chou M.P.,University of Queensland | Clements A.C.A.,University of Queensland | Thomson R.M.,Gallipoli Medical Research Center
BMC Infectious Diseases | Year: 2014

Background: The epidemiology of infections with nontuberculous mycobacteria (NTM) has been changing and the incidence has been increasing in some settings. The main route of transmission to humans is considered to be from the environment. We aimed to describe spatial clusters of cases of NTM infections and to identify associated climatic, environmental and socio-economic variables.Methods: NTM data were obtained from the Queensland Mycobacterial Reference Laboratory for the period 2001-2011. A Bayesian spatial conditional autoregressive model was constructed at the postcode level, with covariates including soil variables, maximum, mean and minimum rainfall and temperature, income (proportion of population earning < $32,000 and < $52,000) and land use category.Results: Significant clusters of NTM infection were identified in the central Queensland region overlying the Surat sub-division of the Great Artesian Basin, as well as in the lower North Queensland Local Government Area known as the Whitsunday region. Our models estimated an expected increase of 21% per percentage increase of population earning < $52,000 (95% CI 9-34%) and an expected decrease of 13% for every metre increase of average topsoil depth for risk of Mycobacterium intracellulare infection (95% CI -3 - -22%). There was an estimated increase of 79% per mg/m3 increase of soil bulk density (95% CI 26-156%) and 19% decrease for every percentage increase in population earning < $32,000 for risk of M. kansasii infection (95% CI -3 - -49%).Conclusions: There were distinct spatial clusters of M. kansasii, M. intracellulare and M. abscessus infections in Queensland, and a number of socio-ecological, economic and environmental factors were found to be associated with NTM infection risk. © 2014 Chou et al.; licensee BioMed Central Ltd.

Affandi J.S.,University of Western Australia | Hendry S.,University of Western Australia | Waterer G.,University of Western Australia | Thomson R.,Gallipoli Medical Research Center | And 3 more authors.
Human Immunology | Year: 2013

The incidence of pulmonary non-tuberculous mycobacteria (NTM) disease in otherwise healthy adults is increasing as the population ages. The organisms are ubiquitous so susceptibility probably reflects a deficiency in a protective immune response. Here we investigate if singlenucleotide polymorphisms (SNP) affecting cytokines, chemokines and their receptors associate with pulmonary NTM disease. Samples from NTM patients (n=79) and healthy controls (n=188) were genotyped using TaqMan probes. Of the 16 SNPs assessed, IL28B-rs8099917*TG (rs8099917; P=0.01, OR=2.2), TNFA-1031*CC (rs1799964; p=0.02, OR=0.48) and IL10-1082*AA (rs1800896; P=0.001, OR=0.33) were significantly associated with NTM disease. IL28B-rs8099917 and IL10-1082 have been associated with perturbations of the Th1/Th2 balance, whilst TNFA-1031*CC associates with sensory neuropathy in HIV patients. IL10-1082 warrants further investigation because we observed high production of IL-10 in blood mononuclear cells from NTM patients. © 2013 American Society for Histocompatibility and Immunogenetics.

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