Does Lyme disease exist in Australia?

There is no convincing evidence that classic Lyme disease occurs in Australia, nor is there evidence that the causative agent, Borrelia burgdorferi, is found in Australian animals or ticks. Lyme disease, however, can be acquired overseas but diagnosed in Australia; most people presenting with laboratory-confirmed Lyme disease in Australia were infected in Europe. Despite the lack of evidence that Lyme disease can be acquired in Australia, growing numbers of patients, their supporters, and some politicians demand diagnoses and treatment according to the protocols of the "chronic Lyme disease" school of thought. Antibiotic therapy for chronic "Lyme disease-like illness" can cause harm to both the individual (eg, cannula-related intravenous sepsis) and the broader community (increased antimicrobial resistance rates). Until there is strong evidence from well performed clinical studies that bacteria present in Australia cause a chronic debilitating illness that responds to prolonged antibiotics, treating patients with "Lyme disease-like illness" with prolonged antibiotic therapy is unjustified, and is likely to do much more harm than good.

Prevalence of asymptomatic SARS-CoV-2 infection in elective surgical patients in Australia: a prospective surveillance study.

BACKGROUND: The study aimed to estimate the prevalence of active or previous SARS-CoV-2 infection in asymptomatic adults admitted for elective surgery in Australian hospitals. This surveillance activity was established as part of the National Pandemic Health Intelligence Plan. METHODS: Participants (n = 3037) were recruited from 11 public and private hospitals in four states (NSW, Vic, SA and WA) between 2 June and 17 July 2020, with an overall 66% participation rate. Presence of SARS-CoV-2 viral RNA was assessed by Reverse Transcriptase - Polymerase Chain Reaction (RT-PCR) analysis of nasopharyngeal swabs taken after induction of anaesthesia. Presence of anti-SARS-CoV-2 antibodies was assessed by analysis of serum collected at the same time using a novel dual-antigen ELISA assay. RESULTS: No patient (0/3010) returned a positive RT-PCR result. The Bayesian estimated prevalence of active infection of 0.02% (95% probability interval 0.00-0.11%), with the upper endpoint being 1 in 918. Positive serology (IgG) was observed in 15 of 2991 patients, with a strong positive in five of those individuals (Bayesian estimated seroprevalence 0.16%; 95% probability interval 0.00-0.47%). CONCLUSION: These results confirm that during periods of low community prevalence of SARS-CoV-2 elective surgery patients without fever or respiratory symptoms had a very low prevalence of active SARS-CoV-2 infection.

Establishment of a surveillance system (utilising Midwifes Data Collection Systems) for monitoring the impact of hepatitis B vaccination on the population prevalence of chronic hepatitis B virus infection in Australia.

OBJECTIVE: To examine how routine hepatitis B surface antigen (HBsAg) testing of antenatal women (as identified on the NT Midwifes Data Collection System) can be used to track the impact of hepatitis B (HBV) vaccination on the prevalence of chronic HBV infection in the Northern Territory (NT). METHODS: Women who gave birth between 01 July 2002 and 30 June 2004 were identified from the NT Midwives Data Collection System (MDCS). For each woman, the unique hospital record number (HRN) was linked to the information system of the NT Government pathology service to obtain the results of serological tests for hepatitis B. The prevalence of HBsAg was calculated by age, Indigenous status, and maternal country of birth. RESULTS: During the study period, 1061 records of women from the NT MDCS could be linked to HBsAg results. Overall, 33 (3.1%) were positive for HBsAg, of whom 29 were recorded as Indigenous and the remaining four were born outside Australia. CONCLUSIONS: Linking data from the NT MDCS and HBsAg results from government pathology service is a feasible means to monitor the impact of HBV vaccination policy. IMPLICATIONS: Routine inclusion of HBsAg results in all state and territory midwives data collections should be pursued.

Indirect hemagglutination assay in patients with melioidosis in northern Australia.

Melioidosis is caused by the saprophytic organism Burkholderia pseudomallei. The use of the indirect hemagglutination assay (IHA) has found widespread use in areas endemic for this disease. Using this assay, we explored the serologic profile of 275 patients with culture-confirmed melioidosis in the Northern Territory of Australia. Based on a threshold titer of 1:40, the sensitivity of the IHA on admission was 56%. Female patients, those with positive blood cultures, and those with pneumonia independently predicted a negative IHA result. Most patients (68%) with negative admission IHA titers subsequently seroconverted. Most patients (92%) with positive admission IHA titers had persistently positive IHA titers. Relapses were not observed in 36 patients who had a negative IHA at least 1 month after admission, irrespective of initial admission IHA. The IHA has limited utility as a diagnostic test for acute disease, and most patients subsequently have persistently positive titers after recovery from illness.

Peritonitis due to Cunninghamella bertholletiae in a patient undergoing continuous ambulatory peritoneal dialysis.

Peritoneal dialysis-associated peritonitis due to fungi of the class Zygomycetes occurs very rarely. A case of fungal continuous ambulatory peritoneal dialysis peritonitis due to Cunninghamella bertholletiae is reported in a 39-year-old Aboriginal woman with end-stage renal failure and diabetes mellitus. This isolate was found to be resistant in vitro to amphotericin B, 5-fluorocytosine, fluconazole, itraconazole, ketoconazole and voriconazole. However, this patient was successfully treated with voriconazole and removal of the Tenckhoff dialysis catheter. Zygomycoses are an emerging threat among immunocompromised patients, including those with chronic renal failure. Zygomycosis due to C. bertholletiae is frequently fatal and is often non-responsive to systemic antifungal therapy. This is believed to be the first reported case of C. bertholletiae causing peritonitis in humans and one of the minority of cases involving this organism with a successful outcome.

Evidence that the gonococcal porA pseudogene is present in a broad range of Neisseria gonorrhoeae strains; suitability as a diagnostic target.

AIMS: The primary aim of the study was to determine if the gonococcal porA pseudogene is a stable sequence target for the detection of Neisseria gonorrhoeae by PCR. METHODS: A total of 240 gonococcal strains from various geographic locations were tested by porA pseudogene PCR. In addition, porA pseudogene PCR positivity rates were compared with established gonococcal assays in three Australian states. RESULTS: All N. gonorrhoeae isolates provided positive results in the porA pseudogene PCR. Positivity rates compared favourably with established gonococcal assays, with increased N. gonorrhoeae detection in the Northern Territory and Western Australia. CONCLUSIONS: The results of this multicentre study provide further evidence that the porA pseudogene is highly conserved across a diverse range N. gonorrhoeae strains and is a suitable PCR target for routine detection of N. gonorrhoeae.

Studies of measles viruses circulating in Australia between 1999 and 2001 reveals a new genotype.

Nineteen distinct measles virus (MV) strains associated with nine different genotypes were identified in five Australian states (Victoria, New South Wales, Queensland, Northern Territory and Western Australia) between 1999 and 2001. One of the strains identified is likely to represent a new genotype within the clade D viruses (proposed to be d9). No evidence for an indigenous MV strain was found. When epidemiologic information associated with the index case was available for the outbreaks, it usually supported introduction of the virus from overseas, with the main source being South East Asia. Changes in the circulation of MV in Australia since the early 1970s were also observed. Prior to the introduction of measles vaccine, the majority of the population acquired immunity through infection with wild-type virus in early childhood. Nowadays in Australia, young adults are at most risk of infection. The age range of cases in the study period was from 1 month to 48 years, with the majority (59%) of cases from individuals aged 18-30 years.

Characterization of a novicida-like subspecies of Francisella tularensis isolated in Australia.

Francisella tularensis is found throughout the Northern Hemisphere, where it is associated with the disease of tularaemia in animals and humans. The isolation and identification is reported of a novicida-like subspecies of F. tularensis from a foot wound sustained in brackish water in the Northern Territory of Australia.

Community-onset methicillin-resistant Staphylococcus aureus bacteremia in Northern Australia.

BACKGROUND: Community-onset infections caused by methicillin-resistant Staphylococcus aureus (COMRSA) are being increasingly reported worldwide. METHODS: A retrospective study was performed of 14 patients with 15 episodes of COMRSA bacteremia (COMRSAB) admitted to the Royal Darwin Hospital, Northern Territory, Australia from 1998 to 2001. Isolates from COMRSAB episodes underwent extended susceptibility testing and molecular typing by pulsed field gel electrophoresis and allotyping of the staphylococcal cassette chromosome mec (SCCmec) region by polymerase chain reaction. RESULTS: The proportion of community-onset S. aureus bacteremia episodes that were due to COMRSA increased from 9% in 1998 to 20% in 2001. The clinical features of COMRSAB were similar to those seen with methicillin-susceptible strains, including sepsis, endocarditis and metastatic infection. Ineffective empiric antimicrobial therapy was administered in the majority (80%) of episodes. All COMRSAB isolates tested contained allotype IV SCCmec, which is commonly found in community isolates of MRSA and rarely found in isolates from healthcare-associated MRSA infection. CONCLUSION: The increasing incidence of COMRSAB in our region has resulted in the addition of vancomycin to standard empiric therapy in certain patients with suspected S. aureus bacteremia acquired in the community.

"Flush before fill" in children receiving automated peritoneal dialysis.

OBJECTIVE: To evaluate the impact of the "flush before fill" technique on the frequency of peritonitis in children receiving automated peritoneal dialysis (APD). DESIGN: Randomized prospective multicenter study. SETTING: Participating pediatric dialysis programs of the Pediatric Peritoneal Dialysis Study Consortium. PATIENTS: 121 pediatric (< 21 years of age) patients that had received peritoneal dialysis for > or = 2 months and that were currently receiving APD were randomized to use (flush group) or non-use (no flush group) of the "flush before fill" option. 66 patients were followed for > or = 12 months. MAIN OUTCOME MEASURE: Peritonitis rates. RESULTS: Overall, patients enrolled in the flush group experienced a peritonitis rate of 1 infection every 16.8 patient months; patients in the no flush group experienced a rate of 1 infection every 12.6 patient months (p = 0.193). However, analysis by gender revealed the peritonitis rate of females in the flush group (1 infection every 44.7 patient months) to be significantly better than females in the no flush group (1 infection every 12.4 patient months) (p < or = 0.01). There was no difference noted in the male patients. CONCLUSION: The use of the "flush before fill" option in pediatric patients receiving APD is associated with a marked improvement in the peritonitis rate of female but not male patients. Further study is indicated to explain the gender differences.

Efficacy and safety of clopidogrel in children with diarrhea associated hemolytic uremic syndrome.

INTRODUCTION: Hemolytic uremic syndrome is a thrombotic microangiopathy. Clopidogrel, a recently developed platelet aggregation inhibitor, has not been previously reported as a treatment for this illness. Our study's objective was to explore the efficacy and safety of clopidogrel in children with diarrhea associated hemolytic uremic syndrome. MATERIALS AND METHODS: We performed a retrospective chart review of all children (≤ 18 years) hospitalized with diarrhea associated hemolytic uremic syndrome. Outcomes in clopidogrel treated children were described. In subgroup analysis, outcomes were compared to those untreated with platelet aggregation inhibitors. RESULTS: Of 72 children with diarrhea associated hemolytic uremic syndrome, 88% were treated with platelet aggregation inhibitors (clopidogrel 56%, sulfinpyrazone 19%, dipyridamole 13%). The median age of clopidogrel treated children was 5 years; 40% were male. Initial median hemoglobin, platelet count, and serum creatinine were 10.1g/dL, 53 × 10(3)/µL, and 2.3mg/dL respectively. Clopidogrel (median dose 1mg/kg/d) was given for a median of 4 days (range 1-15). Other therapies included erythropoietin (98%), red blood cell transfusions (80%), diuretics (58%), anti-hypertensive agents (45%), and dialysis (33%). The median hospital length of stay was 9 days (range 3-26). Three children had bleeding complications (epistaxis/hematemesis). The risk of chronic kidney disease was 5% and death 2.5%. In subgroup analysis, median duration of dialysis was 11 days in thirteen clopidogrel treated children compared to 21 days in five untreated patients (P=0.04). CONCLUSIONS: Children with diarrhea associated hemolytic uremic syndrome treated with clopidogrel have outcomes comparable to untreated patients. Bleeding complications may occur.

Successful utilization of high-flux hemodialysis for treatment of vancomycin toxicity in a child.

Vancomycin is routinely used for empiric antibiotic therapy in children. Higher-serum-concentration targets for serious infections are now being recommended. This recommendation may result in aggressive dosing with increased potential for toxicity. We report a case of a pediatric patient who developed vancomycin toxicity and associated oliguric renal failure who was treated effectively with high-flux hemodialysis for vancomycin toxicity, clearing serum concentrations of vancomycin by over 75% in only 6 hours (213.2 mcg/mL to 51.8 mcg/mL) with subsequent return to baseline renal function and without adverse sequelae. While not historically considered a viable option for drug removal in cases of toxicity, new high-flux hemodialysis techniques can remove significant percentages of vancomycin in short periods of time.

Exploring 'best practice' for nucleic acid detection of Neisseria gonorrhoeae.

Nucleic acid detection tests (NADT) have considerable benefits for the detection of Neisseria gonorrhoeae (GC), including high sensitivity across a range of specimen types and use under widely differing settings and conditions. However, sexual health practitioners and others who use data generated by NADT for GC should be aware of some important limitations of these tests. False-positive results caused by cross reaction with commensal Neisseria species have been observed in many assays, and have lead to unacceptably low positive-predictive values in some patient populations. Further, false-negative results can be caused by GC sequence variation, with some gonococci lacking certain NADT target sequences. This review examines the issues associated with gonococcal NADT and considers best practice for use of these assays based on current knowledge. We emphasise the need for supplementary testing and extensive assay validation, and suggest appropriate strategies for these requirements irrespective of the setting in which they are used. Further, we highlight the need to maintain culture-based testing for certain specimen sites as well as for antimicrobial resistance surveillance.

Guidelines for the use and interpretation of nucleic acid detection tests for Neisseria gonorrhoeae in Australia: a position paper on behalf of the Public Health Laboratory Network.

The Public Health Laboratory Network (PHLN) convened a workshop of Australian experts in Melbourne on 23 March 2005 to identify laboratory issues of relevance and suggest guidelines for use of nucleic acid detection tests (NADT) for diagnosis of gonorrhoea in Australia. The proceedings of that meeting were endorsed by the members of the PHLN and the Communicable Diseases Network of Australia. Given the present state of knowledge and experience of conditions currently existing in Australia, the following recommendations were made: Recommendation 1: Assays using detection of the cppB gene should not be used for either screening or supplemental assays. Recommendation 2: All in-house screening assays that are positive should also be positive on a reliable supplemental assay before a positive result is reported. Recommendation 3: All commercial screening assays that are positive should also be positive on a reliable supplemental assay before a positive result is reported. Recommendation 4: If a sample is positive in a screening assay but a suitable supplemental assay is negative, then the result should be reported as negative. Recommendation 5: Laboratories should ensure that the test combination they use would yield a positive predictive value of at least 90 per cent in a population with a prevalence of 1 per cent. Recommendation 6: For the purposes of test evaluation, as distinct from diagnostic testing, true positives be defined by meeting one or more of the following criteria: 1) culture positive using contemporary isolation and identification techniques; 2) positive result on NADTs directed to targets on three separate genes that are known to have discriminatory capacity; 3) sequencing of a gene known to separate gonococcal from non-gonococcal species. Recommendation 7: Inhibitor controls should be routinely included in all NADT. Recommendation 8: Cultures are the preferred test for samples from non-genital sites. If however it is necessary to perform a NADT, then more stringent criteria should be applied, and positive samples should meet the 'test evaluation' criteria for a 'true positive'. Recommendation 9: In order to properly assess the routine diagnostic system in Australia, the following quality assurance samples should be distributed in addition to the routine samples currently used: 1. cppB negative N. gonorrhoeae; 2. Non-gonococcal species known to cause false positive reactions: these should be dispatched both as a single species, as well as mixture with N. gonorrhoeae. In the latter circumstance, the non-gonococcal species should be present in 10-fold excess; 3. Urine samples: preferably a single patient sample, otherwise a spiked sample. 4. Validation panels should be made that include samples that are culture positive but PCR negative. True positive samples should also be made available. In addition, a process should be established for full phenotypic and genotypic characterisation of unidentified species that yield false positive results in NADT for gonococci. Recommendation 10: Strategies should be put in place to ensure that sufficient numbers of gonococcal isolates are obtained to allow reliable monitoring of antimicrobial resistance. Recommendation 11: Public health practitioners need to define the relevant populations that need to be targeted and identify any that require enhanced surveillance.

Epidemiology of community-acquired and nosocomial bloodstream infections in tropical Australia: a 12-month prospective study.

OBJECTIVES: To define the relative incidence of organisms causing blood stream infections in a tropical setting with a very low prevalence of human immunodeficiency virus infection (<1%). METHODS: A 12-month prospective study of blood stream infections in 2000 at Royal Darwin Hospital in the tropical north of Australia. RESULTS: Significant isolates were grown from 257 sets of blood cultures. Staphylococcus aureus was the most common isolate overall (28%); 26% of these were methicillin-resistant (MRSA). Escherichia coli was the most common cause of community-acquired bacteraemia. Burkholderia pseudomallei caused 32% of community acquired, bacteraemic pneumonia; 6% of bacteraemias overall. Vancomycin-resistant enterococci were not isolated. Crude mortality rates (13% overall; 9% attributable mortality) were lower than in most comparable studies. CONCLUSIONS: The major difference between these findings and surveys performed elsewhere is the presence of B. pseudomallei as a significant cause of bacteraemic community-acquired pneumonia. Our results demonstrate the effects of local environmental and patient characteristics on the range of organisms causing blood stream infections, and emphasize the important role of local microbiology laboratories in guiding empiric antibiotic therapy.