Population-Attributable Risk Estimates for Risk Factors Associated with Campylobacter Infection

In 2001-2002, a multicenter, prospective case-control study involving 1,714 participants ≥5 years of age was conducted in Australia to identify risk factors for Campylobacter infection. Adjusted population-attributable risks (PARs) were derived for eac

Climate variability and Ross River virus infections in Riverland, South Australia, 1992-2004

Ross River virus (RRV) infection is the most common notifiable vector-borne disease in Australia, with around 6000 cases annually. This study aimed to examine the relationship between climate variability and notified RRV infections in the Riverland region of South Australia in order to set up an early warning system for the disease in temperate-climate regions. Notified data of RRV infections were collected by the South Australian Department of Health. Climatic variables and monthly river flow were provided by the Australian Bureau of Meteorology and South Australian Department of Water, Land and Biodiversity Conservation over the period 1992–2004. Spearman correlation and time-series-adjusted Poisson regression analysis were performed. The results indicate that increases in monthly mean minimum and maximum temperatures, monthly total rainfall, monthly mean Southern Oscillation Index and monthly flow in the Murray River increase the likelihood, but an increase in monthly mean relative humidity decreases the likelihood, of disease transmission in the region, with different time-lag effects. This study demonstrates that a useful early warning system can be developed for local regions based on the statistical analysis of readily available climate data. These early warning systems can be utilized by local public health authorities to develop disease prevention and control activities.P. Bi, J. E. Hiller, A. S. Cameron, Y. Zhang and R. Givne

Characteristics of a Widespread Community Cluster of H275Y Oseltamivir-Resistant A(H1N1)pdm09 Influenza in Australia

Background. Oseltamivir resistance in A(H1N1)pdm09 influenza is rare, particularly in untreated community cases. Sustained community transmission has not previously been reported

Antibacterial resistance and their genetic location in MRSA isolated in Kuwait hospitals, 1994-2004

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) continues to be a major cause of serious infections in hospitals and in the community worldwide. In this study, MRSA isolated from patients in Kuwait hospitals were analyzed for resistance trends and the genetic location of their resistance determinants. METHODS: Between April 1994 and December 2004, 5644 MRSA isolates obtained from different clinical samples were studied for resistance to antibacterial agents according to guidelines from the National Committee for Clinical Laboratory Standards and the British Society for Antimicrobial Chemotherapy. The genetic location of their resistance determinants was determined by curing and transfer experiments. RESULTS: They were resistant to aminoglycosides, erythromycin, tetracycline, trimethoprim, fusidic acid, ciprofloxacin, chloramphenicol, rifampicin, mupirocin, cadmium acetate, mercuric chloride, propamidine isethionate and ethidium bromide but susceptible to vancomycin, teicoplanin and linezolid. The proportion of the isolates resistant to erythromycin, ciprofloxacin and fusidic acid increased during the study period. In contrast, the proportion of isolates resistant to gentamicin, tetracycline, chloramphenicol and trimethoprim declined. High-level mupirocin resistance increased rapidly from 1996 to 1999 and then declined. They contained plasmids of 1.9, 2.8, 3.0, 4.4, 27 and 38 kilobases. Genetic studies revealed that they carried plasmid-borne resistance to high-level mupirocin resistance (38 kb), chloramphenicol (2.8 – 4.4 kb), erythromycin (2.8–3.0 kb) and cadmium acetate, mercuric chloride, propamidine isethionate and ethidium bromide (27 kb) and chromosomal location for methicillin, the aminoglycosides, tetracycline, fusidic acid, ciprofloxacin and trimethoprim resistance. Thus, the 27 kb plasmids had resistance phenotypes similar to plasmids reported in MRSA isolates in South East Asia. CONCLUSION: The prevalence of resistance to erythromycin, ciprofloxacin, high-level mupirocin and fusidic acid increased whereas the proportion of isolates resistant to gentamicin, tetracycline, chloramphenicol and trimethoprim declined during the study period. They contained 27-kb plasmids encoding resistance to cadmium acetate, mercuric chloride, propamidine isethionate and ethidium bromide similar to plasmids isolated in MRSA from South East Asia. Molecular typing of these isolates will clarify their relationship to MRSA from South East Asia

Including the public in pandemic planning: a deliberative approach

Background: Against a background of pandemic threat posed by SARS and avian H5N1 influenza, this study used deliberative forums to elucidate informed community perspectives on aspects of pandemic planning. Methods: Two deliberative forums were carried out with members of the South Australian community. The forums were supported by a qualitative study with adults and youths, systematic reviews of the literature and the involvement of an extended group of academic experts and policy makers. The forum discussions were recorded with simultaneous transcription and analysed thematically. Results: Participants allocated scarce resources of antiviral drugs and pandemic vaccine based on a desire to preserve society function in a time of crisis. Participants were divided on the acceptability of social distancing and quarantine measures. However, should such measures be adopted, they thought that reasonable financial, household and psychological support was essential. In addition, provided such support was present, the participants, in general, were willing to impose strict sanctions on those who violated quarantine and social distancing measures. Conclusions: The recommendations from the forums suggest that the implementation of pandemic plans in a severe pandemic will be challenging, but not impossible. Implementation may be more successful if the public is engaged in pandemic planning before a pandemic, effective communication of key points is practiced before and during a pandemic and if judicious use is made of supportive measures to assist those in quarantine or affected by social isolation measures.Annette J Braunack-Mayer, Jackie M Street, Wendy A Rogers, Rodney Givney, John R Moss, Janet E Hiller, Flu Views tea

A Novel Bocavirus Associated with Acute Gastroenteritis in Australian Children

Acute gastroenteritis (AGE) is a common illness affecting all age groups worldwide, causing an estimated three million deaths annually. Viruses such as rotavirus, adenovirus, and caliciviruses are a major cause of AGE, but in many patients a causal agent cannot be found despite extensive diagnostic testing. Proposing that novel viruses are the reason for this diagnostic gap, we used molecular screening to investigate a cluster of undiagnosed cases that were part of a larger case control study into the etiology of pediatric AGE. Degenerate oligonucleotide primed (DOP) PCR was used to non-specifically amplify viral DNA from fecal specimens. The amplified DNA was then cloned and sequenced for analysis. A novel virus was detected. Elucidation and analysis of the genome indicates it is a member of the Bocavirus genus of the Parvovirinae, 23% variant at the nucleotide level from its closest formally recognized relative, the Human Bocavirus (HBoV), and similar to the very recently proposed second species of Bocavirus (HBoV2). Fecal samples collected from case control pairs during 2001 for the AGE study were tested with a bocavirus-specific PCR, and HBoV2 (sequence confirmed) was detected in 32 of 186 cases with AGE (prevalence 17.2%) compared with only 15 controls (8.1%). In this same group of children, HBoV2 prevalence was exceeded only by rotavirus (39.2%) and astrovirus (21.5%) and was more prevalent than norovirus genogroup 2 (13.4%) and adenovirus (4.8%). In a univariate analysis of the matched pairs (McNemar's Test), the odds ratio for the association of AGE with HBoV2 infection was 2.6 (95% confidence interval 1.2–5.7); P = 0.007. During the course of this screening, a second novel bocavirus was detected which we have designated HBoV species 3 (HBoV3). The prevalence of HBoV3 was low (2.7%), and it was not associated with AGE. HBoV2 and HBoV3 are newly discovered bocaviruses, of which HBoV2 is the thirdmost-prevalent virus, after rotavirus and astrovirus, associated with pediatric AGE in this study

A windy day in a sheep saleyard: an outbreak of Q fever in rural South Australia

Published online: 09 May 2014In December 2004, the Department of Human Services investigated an outbreak of Q fever in South Australia. A case-control study tested an association between attending a local saleyard and human illness. A case was defined as a person with clinical illness and evidence of seroconversion or high phase II IgM. Controls were selected from a database of community controls matched on sex, age group and postcode. Matched analysis of the first 15 cases with 45 controls indicated that contracting Q fever was associated with attending the saleyard on one particular day (adjusted odds ratio 15·3, 95% confidence interval 1·7-undefined, P = 0·014). Saleyard conditions were windy and conducive for airborne dispersal of contaminated particles. In total, 25 cases were detected. Of these, 22 cases had attended a local saleyard on the same day. This outbreak suggests cases were probably infected by a single exposure at a saleyard from infected sheep and dust. The investigation resulted in an increase in the local uptake of Q fever vaccination and extension of the Australian national vaccination programme.B. A. O'Connor, I.G. Tribe and R. Givne

Have changes to meat and poultry food safety regulation in Australia affected the prevalence of Salmonella or of salmonellosis?

During the 1990s, there was radical change in regulation of meat and poultry hygiene in Australia, and Australian Standards were developed for each sector of the meat industry. Systems for industry/government co-regulation and company-employed meat inspection were introduced based on company HACCP programs approved and audited by the Controlling Authority. However, in the 5 years since regulatory changes took full effect, rates of salmonellosis have not decreased (surveillance and reporting systems have remained unchanged). Using statistics gathered by the National Enteric Pathogens Surveillance Scheme, an attempt was made to link Salmonella serovars isolated from meat and poultry with those causing salmonellosis. Two periods were studied, 1993/1994, before regulations were introduced, and 2000/2001, when regulations should be having an effect. For red meat, the same serovars were prominent among the top 10 isolates both before and after regulation, and there was little linkage with salmonelloses. For poultry, frequently isolated serovars differed pre- and post-regulation, however, in both periods there was some linkage between serovars isolated from poultry and those causing salmonelloses. Using published and unpublished survey data, it was concluded that there had been improvements in microbiological quality of red meat and poultry over the same timeframe as regulatory changes. That these improvements apparently have not carried through to reduced case-rates for salmonellosis may be due to numerous causes, including lack of control in the food processing, food service and home sectors. The present paper illustrates difficulties faced by governments in measuring public health outcomes of changes to food hygiene regulation.John Sumner, Geoff Raven, Rod Givne

A large prolonged outbreak of human calicivirus infection linked to an aged-care facility

This report investigates an outbreak of acute gastrointestinal illness, microbiologically and epidemiologically linked to an aged-care facility and seeks to determine if there was a point source of infection. A register of cases that included onset date and time of illness and symptoms was maintained by nursing staff. Faecal specimens were tested for conventional gastrointestinal pathogens and for human calicivirus (HuCV). There were 81 cases reported. Specimens were received for testing from 25 cases. Twenty-three of the 25 (92%) specimens were positive for HuCV RNA by reverse transcriptase polymerase chain reaction (RT-PCR). The 2 negative samples contained RT-PCR inhibitors. Descriptive epidemiology suggested that staffing practices were important in prolonging the outbreak. No point source of infection was identified. Instead environmental contamination, aerosol transmission and work practices that fail to take account of the natural history of HuCV infection probably contributed to the size (81 cases) and duration (3 weeks) of this outbreak among the residents, staff and visitors of an aged-care facility and their contacts. Institutional outbreaks caused by HuCV, formerly called Norwalk-like or small round structured viruses, are extremely difficult to control. Infected staff may contribute significantly to the amplification of outbreaks. Rapid confirmation of HuCV infection is now routinely possible using polymerase chain reaction diagnostics but progress in laboratory technology has not yet translated into faster or more effective interventions.Milazzo A, Tribe IG, Ratcliff R, Doherty C, Higgins G and Givney R