Evolution and spread of a highly drug resistant strain of Mycobacterium tuberculosis in Papua New Guinea.

BACKGROUND: Molecular mechanisms determining the transmission and prevalence of drug resistant tuberculosis (DR-TB) in Papua New Guinea (PNG) are poorly understood. We used genomic and drug susceptibility data to explore the evolutionary history, temporal acquisition of resistance and transmission dynamics of DR-TB across PNG. METHODS: We performed whole genome sequencing on isolates from Central Public Health Laboratory, PNG, collected 2017-2019. Data analysis was done on a composite dataset that also included 100 genomes previously sequenced from Daru, PNG (2012-2015). RESULTS: Sampled isolates represented 14 of the 22 PNG provinces, the majority (66/94; 70%) came from the National Capital District (NCD). In the composite dataset, 91% of strains were Beijing 2.2.1.1, identified in 13 provinces. Phylogenetic tree of Beijing strains revealed two clades, Daru dominant clade (A) and NCD dominant clade (B). Multi-drug resistance (MDR) was repeatedly and independently acquired, with the first MDR cases in both clades noted to have emerged in the early 1990s, while fluoroquinolone resistance emerged in 2009 (95% highest posterior density 2000-2016). We identified the presence of a frameshift mutation within Rv0678 (p.Asp47fs) which has been suggested to confer resistance to bedaquiline, despite no known exposure to the drug. Overall genomic clustering was significantly associated with rpoC compensatory and inhA promoter mutations (p < 0.001), with high percentage of most genomic clusters (12/14) identified in NCD, reflecting its role as a potential national amplifier. CONCLUSIONS: The acquisition and evolution of drug resistance among the major clades of Beijing strain threaten the success of DR-TB treatment in PNG. With continued transmission of this strain in PNG, genotypic drug resistance surveillance using whole genome sequencing is essential for improved public health response to outbreaks. With occurrence of resistance to newer drugs such as bedaquiline, knowledge of full drug resistance profiles will be important for optimal treatment selection.

Amikacin Liposome Inhalation Suspension for Treatment-Refractory Lung Disease Caused by Mycobacterium avium Complex (CONVERT). A Prospective, Open-Label, Randomized Study.

Rationale: Improved therapeutic options are needed for patients with treatment-refractory nontuberculous mycobacterial lung disease caused by Mycobacterium avium complex (MAC). Objectives: To evaluate the efficacy and safety of daily amikacin liposome inhalation suspension (ALIS) added to standard guideline-based therapy (GBT) in patients with refractory MAC lung disease. Methods: Adults with amikacin-susceptible MAC lung disease and MAC-positive sputum cultures despite at least 6 months of stable GBT were randomly assigned (2:1) to receive ALIS with GBT (ALIS + GBT) or GBT alone. Once-daily ALIS was supplied in single-use vials delivering 590 mg amikacin to the nebulizer. The primary endpoint was culture conversion, defined as three consecutive monthly MAC-negative sputum cultures by Month 6. Measurements and Main Results: Enrolled patients (ALIS + GBT, n = 224; GBT-alone, n = 112) were a mean 64.7 years old and 69.3% female. Most had underlying bronchiectasis (62.5%), chronic obstructive pulmonary disease (14.3%), or both (11.9%). Culture conversion was achieved by 65 of 224 patients (29.0%) with ALIS + GBT and 10 of 112 (8.9%) with GBT alone (odds ratio, 4.22; 95% confidence interval, 2.08-8.57; P < 0.001). Patients in the ALIS + GBT arm versus GBT alone were more likely to achieve conversion (hazard ratio, 3.90; 95% confidence interval, 2.00-7.60). Respiratory adverse events (primarily dysphonia, cough, and dyspnea) were reported in 87.4% of patients receiving ALIS + GBT and 50.0% receiving GBT alone; serious treatment-emergent adverse events occurred in 20.2% and 17.9% of patients, respectively. Conclusions: Addition of ALIS to GBT for treatment-refractory MAC lung disease achieved significantly greater culture conversion by Month 6 than GBT alone, with comparable rates of serious adverse events. Clinical trial registered with www.clinicaltrials.gov (NCT02344004).

Position statement on interferon-γ release assays for the detection of latent tuberculosis infection.

Interferon-y release assays (IGRAs), such as the Quantiferon (QIFN) TB-Gold Plus assay (Qiagen, Hilden, Germany) and the T-SPOT.TB test (Oxford Immunotec Limited, Abingdon, United Kingdom), are marketed as a substitute for the tuberculin skin test (TST) for the detection of latent tuberculosis infection (LTBI). The relative merits of IGRAs and TST have been hotly debated over the last decade. The specificity of IGRAs has been optimised by using Mycobacterium tuberculosis-specific antigens. However, IGRAs are functional in vitro T-cell-based assays that may lack reproducibility due to specimen collection, transport, processing and kit manufacturing issues. Longitudinal studies comparing the ability of IGRAs and TST to predict the future development of active tuberculosis disease (TB) are the ultimate arbiters on the respective utility of these assays. Three meta-analyses addressing this comparison have now been published and clinical experience with IGRAs is accumulating. The systematic reviews show that IGRAs and TST have similar (but poor) ability to identify patients with LTBI at risk of developing active TB disease. The improved specificity of IGRAs however may reduce the number of patients requiring preventative therapy. Based on these meta-analyses, The National Tuberculosis Advisory Committee (NTAC) now recommends either TST or an IGRA for the investigation of LTBI in most circumstances. Both tests may be used in patients where the risk of progression to active TB disease is high and the disease sequelae potentially severe (eg. LTBI testing in immunocompromised patients or those commencing anti-tumour necrosis factor-a (TNF) therapy). Neither test should be used in the investigation of active TB disease (though TST and/or IGRA may be used as supplementary tests in paediatric cases). The choice of test for serial testing in healthcare workers (HCWs) remains controversial. A preference remains for TST in this circumstance because IGRAs have been bedevilled by higher rates of reversions and conversions when used for serial testing. These recommendations supersede all previous NTAC IGRA statements.

Tuberculosis notifications in Australia, 2014.

In 2014, the National Notifiable Diseases Surveillance System received 1,339 tuberculosis (TB) notifications, representing a rate of 5.7 per 100,000 population. Australia has achieved and maintained good tuberculosis (TB) control since the mid-1980s, sustaining a low annual TB incidence rate of approximately 5 to 6 cases per 100,000 population. The number of multi-drug resistant TB (MDR-TB) cases diagnosed in Australia is low by international standards, with approximately 1-2% of notifications per year being classified as MDR-TB. Australia's overseas-born population continued to represent the majority (86%) of TB notifications and Australia's Aboriginal and Torres Strait Islander population continue to record TB rates around 6 times higher than the Australian born non Indigenous population. Whilst Australia has achieved excellent and sustained control of TB in Australia, sustained effort is still required to reduce rates further and contribute to the achievement of the World Health Organization's goal to end the global TB epidemic by 2035.

Evaluation of bacille Calmette-Guérin immunisation programs in Australia.

BACKGROUND: bacille Calmette-Guérin (BCG) immunisation programs in Australia are funded and operated by the individual states and territories. In recent years BCG vaccine shortages have required use of unregistered products. We aimed to evaluate BCG immunisation programs in Australia, with particular reference to program implementation and national consistency.
 Methods: Between September and November 2015, 12 key stakeholders, representing Australian states and territories, completed surveys. We analysed BCG vaccination coverage data from the Australian Childhood Immunisation Register (ACIR), and data on adverse events following immunisation (AEFI) with BCG vaccine from the Therapeutic Goods Administration's Adverse Drug Reactions System, for 2001 to 2014.
 Results: Access to BCG vaccination varies between jurisdictions, with some states providing this only in major city locations. Analysis of ACIR data suggests significant differences in vaccine delivery between jurisdictions, but varying levels of under-reporting to the ACIR were also acknowledged. The rate of BCG AEFI appeared to increase between 2011 and 2014; however, these data need to be interpreted with caution due to small numbers, likely under-reporting of both numerator (AEFI) and denominator (vaccine doses administered), and the general increase in reporting of AEFI related to other vaccines in children over this period.
 Conclusions: BCG immunisation programs aim to prevent severe forms of tuberculosis in young children who live in or travel to high burden settings. A range of factors, particularly inconsistent vaccine supply are leading to low, variable and inequitable vaccine delivery across Australian jurisdictions. Improved BCG vaccination uptake and AEFI data quality are required for accurate monitoring of program delivery and vaccine safety - this is particularly important given the current need to use unregistered vaccines. Improved and consistent access to BCG vaccine is suggested to optimise equity for at-risk children Australia-wide.

Isolation of nontuberculous mycobacteria (NTM) from household water and shower aerosols in patients with pulmonary disease caused by NTM.

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.

Factors associated with the isolation of Nontuberculous mycobacteria (NTM) from a large municipal water system in Brisbane, Australia.

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.

A five-year analysis of latent tuberculosis infection in Queensland, 2016-2020.

Background Australia is aiming to reach tuberculosis pre-elimination targets by 2035. As a low-incidence setting, control efforts will increasingly rely on the management of latent tuberculosis infection (LTBI). We undertook this descriptive analysis to assess the recent trends of LTBI testing in Queensland. Methods Our objective was to describe the features of LTBI testing in Queensland, and to estimate the range of possible annual notifications were it to be made a notifiable condition. We collated both state-wide and region-specific data on tuberculin skin testing (TST) and interferon gamma release assays (IGRA) conducted in Queensland during the five-year period 1 January 2016 - 31 December 2020. We used reports on Medicare-funded TST and IGRA testing in Queensland, as well as tuberculosis notification data, to understand the representativeness of our data and to derive state-wide estimates. Results We analysed 3,899 public TST, 5,463 private TST, 37,802 public pathology IGRA, and 31,656 private pathology IGRA results. The median age of people tested was 31 years; 57% of those tested were female. From our data sources, an annual average of 1,067 positive IGRA and 354 positive TST results occurred in Queensland. Building on this minimum value, we estimate possible latent tuberculosis notifications in Queensland could range from 2,901 to 6,995 per annum. Private laboratory TSTs are estimated to contribute the lowest number of potential notifications (range: 170-340), followed by private laboratory IGRA testing (range: 354-922), public laboratory IGRA testing (range: 706-1,138), and public setting TSTs (range: 1,671-4,595). Conclusion If LTBI were to be made notifiable, these estimates would place it among the ten most notified conditions in Queensland. This has implications for potential surveillance methods and goals, and their associated system and resource requirements.

Tuberculosis testing.

This article forms part of our 'Tests and results' series for 2012, which aims to provide information about common tests that general practitioners order regularly. It considers areas such as indications, what to tell the patient, what the test can and cannot tell you, and interpretation of results.

Clinical Pharmacokinetic and Pharmacodynamic Considerations in the Drug Treatment of Non-Tuberculous Mycobacteria in Cystic Fibrosis.

Non-tuberculous mycobacteria (NTM) are an emerging group of pulmonary infectious pathogens of increasing importance to the management of patients with cystic fibrosis (CF). NTM include slow-growing mycobacteria such as Mycobacterium avium complex (MAC) and rapidly growing mycobacteria such as Mycobacterium abscessus. The incidence of NTM in the CF population is increasing and infection contributes to significant morbidity to the patient and costs to the health system. Treating M. abscessus requires the combination of multiple costly antibiotics for months, with potentially significant toxicity associated with treatment. Although international guidelines for the treatment of NTM infection in CF are available, there are a lack of robust pharmacokinetic studies in CF patients to inform dosing and drug choice. This paper aims to outline the pharmacokinetic and pharmacodynamic factors informing the optimal treatment of NTM infections in CF.

Amikacin Liposome Inhalation Suspension for Mycobacterium avium Complex Lung Disease: A 12-Month Open-Label Extension Clinical Trial.

Rationale: Patients with refractory Mycobacterium avium complex (MAC) lung disease have limited treatment options. In the CONVERT study, amikacin liposome inhalation suspension (ALIS) added to guideline-based therapy (GBT) increased culture conversion rates versus GBT alone by Month 6. Limited data are available regarding >6-month treatment in a refractory population.Objectives: Evaluate 12-month safety, tolerability, and efficacy of ALIS+GBT.Methods: Adults with refractory MAC lung disease not achieving culture conversion by CONVERT Month 6 could enroll in this open-label extension (INS-312) to receive 590 mg once-daily ALIS+GBT for 12 months. Two cohorts enrolled: the "ALIS-naive" cohort included patients randomized to GBT alone in CONVERT, and the "prior-ALIS" cohort included those randomized to ALIS+GBT in CONVERT. Safety and tolerability of ALIS over 12 months (primary endpoint) and culture conversion by Months 6 and 12 were assessed.Results: In the ALIS-naive cohort, 83.3% of patients (n = 75/90) experienced respiratory treatment-emergent adverse events (TEAEs), and 35.6% (n = 32) had serious TEAEs; 26.7% (n = 24) achieved culture conversion by Month 6 and 33.3% (n = 30) by Month 12. In the prior-ALIS cohort, 46.6% of patients (n = 34/73) experienced respiratory TEAEs, and 27.4% (n = 20) had serious TEAEs; 9.6% (n = 7) achieved culture conversion by Month 6 (≤14 mo ALIS exposure) and 13.7% (n = 10) by Month 12 (≤20 mo ALIS exposure). Nephrotoxicity-related TEAEs and measured hearing decline were infrequent in both cohorts.Conclusions: In up to 20 months of ALIS use, respiratory TEAEs were common, nephrotoxicity and hearing decline were infrequent, and culture conversion continued beyond 6 months of therapy.Clinical trial registered with www.clinicaltrials.gov (NCT02628600).

Analytical performance of the Xpert MTB/XDR® assay for tuberculosis and expanded resistance detection.

In a manufacturer-independent laboratory validation study, the Xpert MTB/XDR® assay demonstrated equivalent limit of detection to Xpert MTB/RIF®, detected 100% of tested resistance mutations and showed some utility for resistance detection in strain mixtures. The Xpert MTB/XDR assay is a reliable, sensitive assay for tuberculosis and expanded resistance detection.

Amikacin Liposome Inhalation Suspension for Refractory Mycobacterium avium Complex Lung Disease: Sustainability and Durability of Culture Conversion and Safety of Long-term Exposure.

BACKGROUND: In the CONVERT study, treatment with amikacin liposome inhalation suspension (ALIS) added to guideline-based therapy (GBT) met the primary end point of increased culture conversion by month 6 in patients with treatment-refractory Mycobacterium avium complex lung disease (ALIS plus GBT, 29% [65/224] vs GBT alone, 8.9% [10/112]; P < .0001). RESEARCH QUESTION: In patients who achieved culture conversion by month 6 in the CONVERT study, was conversion sustained (negative sputum culture results for 12 months with treatment) and durable (negative sputum culture results for 3 months after treatment) and were there any additional safety signals associated with a full treatment course of 12 months after conversion? STUDY DESIGN AND METHODS: Adults were randomized 2:1 to receive ALIS plus GBT or GBT alone. Patients achieving culture conversion by month 6 continued therapy for 12 months followed by off-treatment observation. RESULTS: More patients randomized to ALIS plus GBT (intention-to-treat population) achieved conversion that was both sustained and durable 3 months after treatment vs patients randomized to GBT alone (ALIS plus GBT, 16.1% [36/224] vs GBT alone, 0% [0/112]; P < .0001). Of the patients who achieved culture conversion by month 6, 55.4% of converters (36/65) in the ALIS plus GBT treated arm vs no converters (0/10) in the GBT alone arm achieved sustained and durable conversion (P = .0017). Relapse rates through 3 months after treatment were 9.2% (6/65) in the ALIS plus GBT arm and 30.0% (3/10) in the GBT alone arm. Common adverse events among ALIS plus GBT-treated patients (dysphonia, cough, dyspnea, hemoptysis) occurred mainly within the first 8 months of treatment. INTERPRETATION: In a refractory population, conversion was sustained and durable in more patients treated with ALIS plus GBT for 12 months after conversion than in those treated with GBT alone. No new safety signals were associated with 12 months of treatment after conversion. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT02344004; URL: www.clinicaltrials.gov.

Identification of an unusual Brucella strain (BO2) from a lung biopsy in a 52 year-old patient with chronic destructive pneumonia.

BACKGROUND: Brucellosis is primarily a zoonotic disease caused by Brucella species. There are currently ten Brucella spp. including the recently identified novel B. inopinata sp. isolated from a wound associated with a breast implant infection. In this study we report on the identification of an unusual Brucella-like strain (BO2) isolated from a lung biopsy in a 52-year-old patient in Australia with a clinical history of chronic destructive pneumonia. RESULTS: Standard biochemical profiles confirmed that the unusual strain was a member of the Brucella genus and the full-length 16S rRNA gene sequence was 100% identical to the recently identified B. inopinata sp. nov. (type strain BO1(T)). Additional sequence analysis of the recA, omp2a and 2b genes; and multiple locus sequence analysis (MLSA) demonstrated that strain BO2 exhibited significant similarity to the B. inopinata sp. compared to any of the other Brucella or Ochrobactrum species. Genotyping based on multiple-locus variable-number tandem repeat analysis (MLVA) established that the BO2 and BO1(T) strains form a distinct phylogenetic cluster separate from the other Brucella spp. CONCLUSION: Based on these molecular and microbiological characterizations, we propose that the BO2 strain is a novel lineage of the newly described B. inopinata species.

Tuberculosis notifications in Australia, 2015-2018.

ABSTRACT: In 2018, the National Notifiable Diseases Surveillance System received 1,438 tuberculosis (TB) notifications, representing a rate of 5.8 per 100,000 population, consistent with the preceding three years. Australia has achieved and maintained good tuberculosis (TB) control since the mid-1980s, sustaining a low annual TB incidence rate of approximately five to six cases per 100,000 population. The number of multi-drug-resistant TB (MDR-TB) cases diagnosed in Australia is low by international standards, with approximately 2% of TB notifications per year classified as MDR-TB. Australia's overseas-born population continue to represent the majority of TB notifications (between 86% to 89% across the four reporting years) and the Aboriginal and Torres Strait Islander population continues to record TB rates around four to five times higher than the Australian-born Non-Indigenous population. Whilst Australia has achieved and maintained excellent control of TB in Australia, sustained effort is required to reduce local rates further, especially among Aboriginal and Torres Strait Islander populations, and to contribute to the achievement of the World Health Organization's goal to end the global TB epidemic by 2035.

The clinical significance of Mycobacterium triplex.

OBJECTIVES: Mycobacterium triplex is a slow-growing nontuberculous mycobacteria (NTM) and is a rare cause of human disease. The pathogenicity, natural history and spectrum of disease is unknown. The aim of this study was to review the clinical features, outcomes and drug susceptibility testing (DST) of all M. triplex isolates in Queensland, Australia to guide management of this rare NTM infection in the future. METHODS: This retrospective study included all patients who isolated M. triplex in Queensland, Australia from the 1st January 2000 to 31st December 2016. Clinical information was obtained from medical records to determine the clinical significance of isolates, natural history of disease and treatment outcomes. DST was performed on 15 isolates. RESULTS: Forty-three patients (21 male) had positive cultures for M. triplex. Thirty-nine patients had isolates from pulmonary specimens and 17 (43.6%) met the American Thoracic Society criteria for NTM lung disease. Six patients with pulmonary infection received antimicrobial therapy with 5 patients demonstrating treatment success. Four patients had localised extrapulmonary disease and were cured with surgical management ±â€¯antimicrobial therapy. DST suggests 93% of isolates are susceptible to macrolides. CONCLUSION: This is the largest case series of M. triplex isolates and confirms it is a rare human pathogen. Extrapulmonary disease responded well to surgical management. Treatment of M. triplex pulmonary disease is challenging, and the optimal antimicrobial regimen is unknown. However, the DST data suggests macrolide resistance is rare and macrolides should be included in treatment regimens.

Comparison of methods for processing drinking water samples for the isolation of Mycobacterium avium and Mycobacterium intracellulare.

Several protocols for isolation of mycobacteria from water exist, but there is no established standard method. This study compared methods of processing potable water samples for the isolation of Mycobacterium avium and Mycobacterium intracellulare using spiked sterilized water and tap water decontaminated using 0.005% cetylpyridinium chloride (CPC). Samples were concentrated by centrifugation or filtration and inoculated onto Middlebrook 7H10 and 7H11 plates and Lowenstein-Jensen slants and into mycobacterial growth indicator tubes with or without polymyxin, azlocillin, nalidixic acid, trimethoprim, and amphotericin B. The solid media were incubated at 32 degrees C, at 35 degrees C, and at 35 degrees C with CO(2) and read weekly. The results suggest that filtration of water for the isolation of mycobacteria is a more sensitive method for concentration than centrifugation. The addition of sodium thiosulfate may not be necessary and may reduce the yield. Middlebrook M7H10 and 7H11 were equally sensitive culture media. CPC decontamination, while effective for reducing growth of contaminants, also significantly reduces mycobacterial numbers. There was no difference at 3 weeks between the different incubation temperatures.

Burkholderia cepacia complex epidemiology in persons with cystic fibrosis from Australia and New Zealand.

The Burkholderia cepacia complex (Bcc) is a group of significant opportunistic respiratory pathogens which affect people with cystic fibrosis. In this study, we sought to ascertain the epidemiology and geographic species distribution of 116 Bcc isolates collected from people with CF in Australia and New Zealand. We performed a combination of recA-based PCR, amplified rDNA restriction analysis (ARDRA), pulsed-field gel electrophoresis and repetitive extragenic palindromic PCR on each isolate. Each Burkholderia cenocepacia isolate was also screened by PCR for the presence of the B. cepacia epidemic strain marker. One hundred and fourteen isolates were assigned to a species using recA-based PCR and ARDRA. B. cenocepacia, B. multivorans and B. cepacia accounted for 45.7%, 29.3% and 11.2% of the isolates, respectively. Strain analysis of B. cenocepacia revealed that 85.3% of the isolates were unrelated. One related B. cenocepacia strain was identified amongst 15 people. Whilst full details of person-to-person contact was not available, all patients attended CF centres in Queensland (Qld) and New South Wales (NSW). Although person-to-person transmission of B. cenocepacia strains has occurred in Australia, the majority of CF-related Bcc infections in Australia and New Zealand are most likely acquired from the environment.