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Australia currently has no system of passive surveillance of antimicrobial resistance in spite of the importance of surveillance in identifying and defining emergent resistance being generally accepted. Queensland Health Pathology and Scientific Services have developed flexible software for passive surveillance with the capacity to handle national data. The system imports raw data strings in delimited ASCII text format into a relational database and screens to exclude duplicates before the processing of the cumulative susceptibility data. It allows considerable flexibility in inquiry parameters and has the ability to 'drill down' to individual laboratory results. Examples of analytical output are given for 49,169 unique isolate results obtained in all Queensland Health Pathology Service laboratories from 1 January to 30 June 2003. The system could form the basis of a national system for passive antimicrobial resistance surveillance.

Increasing reports of the appearance of novel nonmultiresistant methicillin-resistant Staphylococcus aureus MRSA (MRSA) strains in the community and of the spread of hospital MRSA strains into the community are cause for public health concern. We conducted two national surveys of unique isolates of S. aureus from clinical specimens collected from nonhospitalized patients commencing in 2000 and 2002, respectively. A total of 11.7% of 2,498 isolates from 2000 and 15.4% of 2,486 isolates from 2002 were MRSA. Approximately 54% of the MRSA isolates were nonmultiresistant (resistant to less than three of nine antibiotics) in both surveys. The majority of multiresistant MRSA isolates in both surveys belonged to two strains (strains AUS-2 and AUS-3), as determined by pulsed-field gel electrophoresis (PFGE) and resistogram typing. The 3 AUS-2 isolates and 10 of the 11 AUS-3 isolates selected for multilocus sequence typing (MLST) and staphylococcal chromosomal cassette mec (SCC mec ) analysis were ST239-MRSA-III (where ST is the sequence type) and thus belonged to the same clone as the eastern Australian MRSA strain of the 1980s, which spread internationally. Four predominant clones of novel nonmultiresistant MRSA were identified by PFGE, MLST, and SCC mec analysis: ST22-MRSA-IV (strain EMRSA-15), ST1-MRSA-IV (strain WA-1), ST30-MRSA-IV (strain SWP), and ST93-MRSA-IV (strain Queensland). The last three clones are associated with community acquisition. A total of 14 STs were identified in the surveys, including six unique clones of novel nonmultiresistant MRSA, namely, STs 73, 93, 129, 75, and 80slv and a new ST. SCC mec types IV and V were present in diverse genetic backgrounds. These findings provide support for the acquisition of SCC mec by multiple lineages of S. aureus . They also confirm that both hospital and community strains of MRSA are now common in nonhospitalized patients throughout Australia.

An annual survey of antimicrobial resistance in clinical isolates of Staphylococcus aureus was conducted in 21 Australian teaching hospital microbiology laboratories in eight major cities from 1989 to 1999. A total of 19,000 isolates were tested for susceptibility to 18 antimicrobials, with 3795 being methicillin-resistant (MRSA). Resistance to ciprofloxacin in MRSA increased from 4.9% to 75.9%. The proportion of MRSA resistant to erythromycin decreased significantly (99.0%-88.9%), as did that to trimethoprim (98.4%-82.4%) and to tetracycline (96.5%-80.1%). The proportion of MRSA isolated increased in Sydney, Melbourne, Canberra, Adelaide, Perth, and Darwin, but not in Brisbane. The proportion in Hobart peaked in 1994. MRSA in Perth were predominantly non-multiresistant (nmMRSA) throughout the survey (i.e., resistant to less than three of eight indicator antibiotics) due mainly to local strains that originated in the community. The proportion of nmMRSA increased to modest levels in the other cities. In eastern cities, this was due to the appearance of strains closely related to nmMRSA seen in other countries of the southwestern Pacific.

The Australian Group for Antimicrobial Resistance (AGAR) has played a unique role in surveillance of antimicrobial resistance in Australia. It has a broad laboratory membership representing the major teaching hospitals in all Australian capitals and more recently major private pathology laboratories in most states. The use of an active surveillance strategy with standard methodology for collection and examination of clinically significant isolates has produced data accurately reflecting the changing prevalence of antimicrobial resistance in major hospitals as well as the community. AGAR has documented the spread of methicillin-resistant Staphylococcus aureus in Australian hospitals in the late 1980s and throughout the 1990s. Surveys of antimicrobial resistance in enterococci have monitored the emergence of vancomycin-resistant enterococci as an important nosocomial pathogen in Australia. AGAR has also conducted major national surveys of resistance in Streptococcus pneumoniae, community isolates of Staphylococcus aureus, Haemophilus influenzae and in the Enterobacteriaceae. These and other activities have given AGAR a unique perspective on emerging patterns of resistance in key pathogens in Australia. The recent extension of membership to include more private pathology laboratories may provide the opportunity to conduct more representative community based surveys.

The region surrounding mecA in methicillin-resistant Staphylococcus aureus (MRSA) is highly variable. We describe an approach for the rapid genotyping of MRSA by assaying for the presence or absence of variable or mobile elements previously shown to be associated with the mecA region.

Aim Australia has a low incidence of hepatitis A virus (HAV), with the majority of cases in travellers. Nonetheless, the sero-prevalence of antibodies against HAV among Victorians has increased over the last two decades, likely to be a result of vaccination and increased travel/immigration. This study measured the prevelance of HAV antibodies in blood donors from around Australia to determine if a similar rate exists in other states. Methods Samples were collected from donors between January and July 2011 from Australian capital cities. All samples ( n = 2109) were tested with a commercially available enzyme immunoassay for total anti-HAV antibody (levels ≥ 20IU/mL were considered sero-positive). Results Anti-HAV antibody was detected in 51.4% (95% CI 49.27-53.53%) of donors. Some variability was observed between cities; the highest rates were seen in Sydney donors (57.33%; 95% CI 51.74-62.93%), while the lowest in donors from Brisbane (43.67%; 95% CI 38.05-49.28%). Not surprisingly, sero-prevelance increased with increasing donor age. Conclusions This study demonstrated that over half of donors tested had anti-HAV antibodies, with relatively high rates in all capital cities. Given increased HAV vaccination rates, measuring naturally-acquired HAV infection in blood donors has become increasingly difficult and a serological test discriminating naturally-occurring from vaccine-induced immunity may be of interest.

Accurate and rapid diagnosis of novel influenza A(H1N1) infection is critical for minimising further spread through timely implementation of antiviral treatment and other public health based measures. In this study we developed two TaqMan-based reverse transcription PCR (RT-PCR) methods for the detection of novel influenza A(H1N1) virus targeting the haemagglutinin and neuraminidase genes. The assays were validated using 152 clinical respiratory samples, including 61 Influenza A positive samples, collected in Queenland, Australia during the years 2008 to 2009 and a further 12 seasonal H1N1 and H3N2 influenza A isolates collected from years 2000 to 2002. A wildtype swine H1N1 isolate was also tested. RNA from an influenza A(H1N1) virus isolate (Auckland, 2009) was used as a positive control. Overall, the results showed that the RT-PCR methods were suitable for sensitive and specific detection of novel influenza A(H1N1) RNA in human samples.

The Australian Group on Antimicrobial Resistance (AGAR) provide national reports on Methicillin resistant and methicillin sensitive Staphylococcus aureus (MRSA) antibiogram patterns for 14 antibiotics based on a decade of using the First 100 clinical isolates from inpatients and outpatients tested in participating laboratories. The First 100 isolates provided by 5 Queensland hospitals to AGAR represent inpatient isolates for every second year, 2005 to 2009, and outpatients for every second year, 2000 to 2008. Validity of the resistance patterns idenitfied by the samples is imperative for national surveillance.

David Whiley, Ella Trembizki, Melanie Syrmis, Jenny Nakos, Cheryl Bletchly, Michael Nissen, Graeme Nimmo and Theo P Sloots Queensland Paediatric Infectious Diseases Laboratory, Royal Children’s Hospital, Brisbane, Qld 4029, Australia Queensland Children’s Medical Research Institute, Royal Children’s Hospital, The University of Queensland, Brisbane, Qld 4029, Australia Pathology Queensland Central Laboratory, Herston, Qld 4029, Australia Griffith University School of Medicine, Southport, Qld 4215, Australia Corresponding author. Tel: +61 7 3636 1623, Fax: +61 7 3636 1401, Email: d.whiley@uq.edu.au

Sixty clinical isolates of Cryptococcus neoformans var. neoformans were analyzed by random amplification of polymorphic DNA (RAPD) using 12- to 22-mer primers in pairs. Five major profiles, which clearly distinguished between serotypes A (profiles I-III), AD (profile IV), and D (profile V), were identified. Forty-two of 58 serotype A isolates were assigned to profile I, 13 to profile II, and 3 to profile III. Profile I compromised 5 subtypes (profiles Ia-Ie), with 37 to 42 isolates in profile Ia. Twenty-seven of 28 isolates from patients with AIDS belonged to profile Ia (P

A fluorescence polarization immunoassay (FPI) for teicoplanin that uses the TDx Instrument System (Abbott, Irving, Tex.) as an automated analyzer has been developed by Innotron of Oregon Inc. and was evaluated in patients with staphylococcal infections enrolled in a clinical trial of the antibiotic. The assay proved accurate in estimating concentrations of between 5 and 100 mg/liter. The intraassay coefficient of variation was < 7.3%, while the interassay variance was < 11.6% against three commercially prepared standards at known concentrations of approximately 5, 35, and 75 mg/liter. Against routinely prepared standards at 10 concentrations between 5 and 100 mg/liter analyzed in a single run, the coefficient of variance did not exceed 4.3%. Compared with bioassay, the FPI demonstrated good correlation in terms of reliability (r = 0.909) in samples containing teicoplanin only and specificity (r = 0.916) in samples containing both teicoplanin and gentamicin. With a turnaround time of 20 min and with only 50 microliters of serum needed for estimation of the amount of drug in a sample, the FPI described here should provide a useful method of teicoplanin measurement in routine diagnostic laboratories.

Bacteraemic sepsis has a high mortality that can be reduced by early diagnosis and initiation of appropriate antimicrobial therapy 1. Rapid confirmation of the diagnosis and identification of the causal agent provide guidance on the adequacy and duration of antimicrobial therapy and on the need for source investigation. Clinical microbiology laboratories have rightly placed great emphasis on this aspect of their practice. As causal organisms are usually present in low titre, direct microscopy is impractical and laboratories have generally relied on culture of blood in broth, which is relatively insensitive and too slow to influence initial management. Phenotypic methods for the identification and antimicrobial susceptibility testing (AST) of isolates have progressively improved over the last two decades, but still require significant periods of incubation. Similarly, commercial blood culture systems have been refined with better systems for automated detection of growth in broth, but still require incubation for up to five days and subculture for the isolation of pathogens. Constantly monitored blood culture systems and automated identification/AST are now the norm in most clinical laboratories. Although there will undoubtedly be further development of phenotypic methods, with incremental improvements in sensitivity and time-to-detection, research and development now concentrated on molecular detection methods has the potential to result in a paradigm shift in our approach to the microbiological diagnosis of this condition.

Two patients presented with culture proven Paecilomyces corneal infection, and a further patient with histologic evidence of fungal infection, on deep corneal biopsy. In all three cases the corneal infection was macroscopically present only in the depth of the cornea and on the endothelial surface with an intact epithelium and no overlying stromal involvement. Repeated surgery with large corneo-scleral grafts in two cases, and with medical therapy and a small patch-graft alone in the third case, resulted in long-term eradication of the infection and preservation of the globes. Antecedent modulation with steroid and/or cyclophosphamide may well have delayed the diagnosis, however, as there was no history of trauma in any of these cases, we postulate that these infections were not exogenously derived.

Aim To determine the prevalence of toxic shock gene tst in an Australian Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) cohort collected over the last two decades. Method The identity of 300 S. aureus isolates was confirmed by real-time polymerase chain reaction (PCR) assays for mecA, nuc and 16S rRNA. Isolates were assayed for eight single nucleotide polymorphisms (SNPs) and for five binary genes (pvl, cna, sdrE, pUB110, pT181). SNP profiles are concordant with multilocus sequence typing (MLST) clonal complexes (CCs) and/or sequence types (STs). Two real-time PCR assays were developed for tst, based on primer sequences previously described. Results SNP profiles correlated with 21 CCs/STs. The 90 MRSA isolates correlated with three CCs: CC239, CC1 and CC22. We found 18 tst positive isolates, 3/91 (1989), 6/104 (1996) and 9/105 (2003). Of these, CC30 was predominant. Of 210 methicillin-sensitive S. aureus isolates, 26 were CC1, 24 CC5 and 23 CC78. Conclusions The proportion of tst positive isolates and binary genes including pvl was low, and has not increased significantly. Most tst positive isolates belong to CC30 which accords with overseas publications. In 1989 and 1996 CC239 MRSA (AUS-2/3) was the sole MRSA strain. MRSA decreased significantly in 2003 in spite of the appearance of CC1 MRSA (WA-1) and CC22 MRSA (EMRSA-15).

A 44-year-old woman with proven Acanthamoeba keratitis was successfully treated medically with resultant 6/9 vision. During the treatment, repeated attempts to titrate the patient off topical corticosteroids resulted in recurrent flare-up of inflammatory keratitis from which Acanthamoeba could not be recultured. It is suggested that steroid administration during the course of Acanthamoeba keratitis may need to be withdrawn extremely slowly to avoid the recurrence of what appears to be an immunological corneal reaction.

Methicillin-resistant Staphylococcus aureus (MRSA) has presented challenges to laboratories and clinicians since it first appeared in Australia in the mid-1960s. However, in spite of its long presence and familiarity, a clear understanding of its epidemiology has only been possible with the recent advent of sequence-based typing methods (see the article by O?Brien and Giffard, page 131).

Objective To determine whether group A streptococcal infection and poststreptococcal sequelae are still a significant health issue for Aboriginal communities. Design A cross-sectional survey of streptococcal carriage, infection and antibody levels. Setting A north Queensland Aboriginal community. Participants One hundred and twenty preschool and school-aged children (2 to 12 years of age) living in the Lockhart River Community on Cape York Peninsula. Results Pyoderma was present in 43% of the children and in 76% of these culture of skin lesions grew group A streptococci. Group A streptococci also grew from 13% of throat swabs, making a total of 36% of children culture positive. Anti-streptolysin O and anti-DNAase B levels were remarkably high and increased with age. Conclusions The evidence presented confirms a high level of group A streptococcal carriage and infection in children of the Lockhart River Community. Further investigation of this problem is warranted in other Aboriginal communities with a view to instituting appropriate control programs.

International audience; Infections caused by community-acquired (CA)-methicillin-resistant Staphylococcus aureus (MRSA) have been reported worldwide. We assessed whether any common genetic markers existed among 117 CA-MRSA isolates from the United States, France, Switzerland, Australia, New Zealand, and Western Samoa by performing polymerase chain reaction for 24 virulence factors and the methicillin-resistance determinant. The genetic background of the strain was analyzed by pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). The CA-MRSA strains shared a type IV SCCmec cassette and the Panton-Valentine leukocidin locus, whereas the distribution of the other toxin genes was quite specific to the strains from each continent. PFGE and MLST analysis indicated distinct genetic backgrounds associated with each geographic origin, although predominantly restricted to the agr3 background. Within each continent, the genetic background of CA-MRSA strains did not correspond to that of the hospital-acquired MRSA.