Alistair McGregor

Clostridium difficile laboratory testing in Australia and New Zealand: national survey results and Australasian Society for Infectious Diseases recommendations for best practice

Aims: In order to improve the future reliability of surveillance for Clostridium difficile infection (CDI), an Australia/New Zealand-wide survey was conducted to examine methods of laboratory diagnosis in use, identify deficiencies in practice and burden of CDI. Methods: An online survey of 48 Australian and New Zealand microbiology laboratories (private and public) was conducted in late 2009 and 2010 to collect information about methods of detection in use and collective testing experience from July 2008 to June 2009. Results: The overall prevalence (proportion positive of all faecal specimens tested) of C. difficile in 123 574 tested samples was 5.3%. The incidence rate across jurisdictions varied between 18.0 per 100 000 population in Victoria to 35.8 per 100 000 population in Tasmania, with a mean for Australia of 25.6 per 100 000 population. The incidence rate in New Zealand was 21.5 per 100 000 population. Most laboratories (60%) screened stools with an enzyme immunoassay (EIA) or equivalent that detected both toxins A and B. Conclusions: The low overall rates reported here may reflect the lack of sensitivity of diagnostic testing procedures currently used in Australia and New Zealand to detect C. difficile. Recommendations for best practice in diagnosis of C. difficile were developed by the Australasian Society for Infectious Diseases (ASID) C. difficile working party and later endorsed by ASID.

Methods to evaluate environmental cleanliness in healthcare facilities

Abstract Background The role of environment in infection prevention and control is being increasingly acknowledged. However, gaps remain between what is promoted as best practice in the literature and what is occurring in healthcare settings. In part, this is due to a lack of generally accepted scientific standards, further confounding the ability to demonstrate an undisputed role for the healthcare environment in healthcare-acquired infections (HAIs). Evaluating environmental cleanliness in a standardised format is required, in order to enable a framework for performance management and provide a method by which interventions can be evaluated. Standardised assessment would provide reliable data to support quality-improvement activities and to ensure that healthcare staff have relevant and useful information to inform and adapt practice. Methods This integrative literature reviewdescribes approaches to assessing environmental cleanliness. A search of the published literature was undertaken, in combination with a targeted review of the grey literature. Results Four methods for assessing environmental cleanliness were identified: visual inspection, fluorescent gel marker, adenosine triphosphate (ATP) and microbial cultures. Advantages and disadvantages for each are explored. Conclusion Methods that evaluate cleaning performance are useful in assessing adherence to cleaning protocols, whereas methods that sample bio-burden provide a more relevant indication of infection risk. Fast, reproducible, costeffective and reliable methods are needed for routine environmental cleaning evaluation in order to predict timely clinical risk.

An outbreak of human rhinovirus species C infections in a neonatal intensive care unit.

We describe an outbreak of human rhinovirus type C infection in 7 infants in our neonatal/pediatric intensive care unit. Five infants had clinically significant apneic episodes and 5 required increased oxygen or ventilatory support. Infants shed virus detectable by polymerase chain reaction for a median of 4 weeks.

Sensitivity and specificity of serology in determining recent acute Campylobacter infection.

Abstract

Francisella tularensis subspecies holarctica, Tasmania, Australia, 2011.

We report a case of ulceroglandular tularemia that developed in a woman after she was bitten by a ringtail possum (Pseudocheirus peregrinus) in a forest in Tasmania, Australia. Francisella tularensis subspecies holarctica was identified. This case indicates the emergence of F. tularensis type B in the Southern Hemisphere.

Not only ‘Flinders Island’ spotted fever

Aim: To demonstrate that Flinders Island spotted fever (FISF), a spotted fever group rickettsial infection caused by Rickettsia honei, is found not only on Flinders Island (Bass Strait), Tasmania, but elsewhere in south‐east Australia. Methods: Cases of FISF were identified by rickettsial serology, culture and the detection of rickettsial DNA via PCR. Isolates and PCR products were sequenced to identify the aetiological agent as R. honei. Results: Three new cases of FISF were detected outside of Flinders Island. One on Schouten Island, south of the Freycinet Peninsula, Tasmania, and two in south‐eastern South Australia (McLaren Vale and Goolwa). Conclusions: These cases show that FISF extends beyond Flinders Island and most likely has the same distribution across south‐east Australia as its vector, the reptile tick Aponomma hydrosauri. FISF should be considered as a differential diagnosis in patients from south‐eastern Australia presenting with fever, headache and rash following a tick bite.

ASID (HICSIG)/AICA Position Statement: preventing catheter-associated urinary tract infections in patients

Catheter-associated urinary tract infections (CAUTIs) occur frequently in healthcare settings. The insertion and maintenance of indwelling urinary catheters is a routine element of healthcare. In order to prevent CAUTI, it is important that healthcare professionals providing catheter care understand the indications for catheter use and the correct procedure for insertion and maintenance of catheters. This paper reviews and summarises three recent key publications on the prevention of CAUTIs and proposes the use of a care bundle and checklist for catheter indications, insertion and maintenance, and quality improvement.

Clostridium difficile infection in Tasmanian public hospitals 2006–2010

Abstract Objective To describe the current epidemiology of Clostridium difficile infection (CDI) in Tasmania Design, setting and participants Tasmania undertakes continuous surveillance for CDI at all public hospitals. Data on cases of CDI between 2006 and 2010 were examined. All positive tests occurring within 8 weeks of a previous case, and cases occurring in children less than 2 years old were excluded, consistent with national definitions. Only cases identified at public hospitals were included in the analysis Main outcome measures The rate of CDI in Tasmanian hospitals over the study period and the ability to demonstrate the effect of variances in surveillance definitions. Results A total of 357 cases of CDI were reported over the study period – a rate of 3.08 per 10 000 patient care days (95%CI 2.90–3.27) or 0.94 per 1000 patient separations (95%CI 0.91–0.98) for hospital-identified cases of CDI. Yearly rates for the period 2006 to 2010 were 2.3, 3.2, 2.8 and 3.9 per 10 000 patient care days, respectively. The overall trend was an increase in cases over the study period. The CDI rate from 2009–10 was significantly higher than that from 2008–09. Of the total cases reported,64% were healthcare-associated, healthcare-facility onset (HCAHFO), equating to a rate of 2.1 per 10 000 patient care days over the 4-year period. Conclusion The Tasmanian rate of HCA HFO is increasing, and appears to be greater than that reported by other Australian states, but is less than many northern hemisphere regions, where hypervirulent strains of C. difficile are causing increasing morbidity and mortality. It is difficult to compare reported rates of CDI nationally and internationally owing to inconsistencies in study duration, denominator selection, testing effort and testing methodology. This study demonstrates the need for national standards for CDI testing and reporting.

An increase in community onset Clostridium difficile infection: a population-based study, Tasmania, Australia

Abstract Background In early 2012, the Tasmanian Infection Prevention and Control Unit identified a 53% increase in the number of cases of Clostridium difficile infection (CDI) identified in Tasmanian public hospitals. To understand this issue further, we undertook a population-based study. The aim of this research was to examine the epidemiology of CDI in Tasmania, with an overarching objective of understanding whether the increase seen in late 2011 was isolated to hospitals or represented a wider phenomenon. Methods A population-based study design was used. All cases of laboratory diagnosed CDI that occurred during 2010 and 2011 in Tasmania were identified. Association of the cases with healthcare were determined using national and international CDI surveillance definitions. Results Atotal of 459 cases of CDI from 438 individuals were identified. The incidence of CDI for the study period was 45 per 100 000 persons per year, 95% CI [41–49]. The relative risk (RR) of CDI was significantly higher in females, compared with males, RR 1.27, P = 0.01, 95% CI [1.06–1.54]. We estimate that the incidence of community associated CDI increased from 10 per 100 000 population in 2010, 95% CI [7.5–13.2] to 17 per 100 000 population in 2011 95% CI [14–21.5]. Conclusion Tasmania experienced a sudden and substantial increase in the number of CDI cases in late 2011. This was most likely linked to transmission and infection pathways in the community, not inside hospitals. This hypothesis requires further testing on a larger scale.

Clostridium difficile infection: an update for infection control practitioners

Clostridium difficile is a common healthcare-associated infection that causes significant patient morbidity and mortality, as well as adding to the cost of healthcare. Almost all cases follow the use of antibiotics, and the major reservoir of infection is infected patients in hospitals or long-term care facilities. The emergence of a novel strain of C. difficile (NAP1/BI/027) around the world has been associated with increased frequency, severity and relapse of C. difficile disease. Principles of C. difficile prevention include antibiotic stewardship, monitoring of incidence and outbreaks, appropriate use of contact precautions, accurate identification of infected patients, consistent hand hygiene and improved environmental cleaning. A variety of surveillance systems and definitions have been used to monitor infection rates. Recently published internationally recognised recommendations and definitions support implementation of an appropriate surveillance program in Australia, endorsed by the Australian Health Ministers Conference in 2008.