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.

Assessment of a novel marker of ICU strain, the ICU Activity Index, during the COVID-19 pandemic in Victoria, Australia.

Objectives: To validate a real-time Intensive Care Unit (ICU) Activity Index as a marker of ICU strain from daily data available from the Critical Health Resource Information System (CHRIS), and to investigate the association between this Index and the need to transfer critically ill patients during the coronavirus disease 2019 (COVID-19) pandemic in Victoria, Australia. Design: Retrospective observational cohort study. Setting: All 45 hospitals with an ICU in Victoria, Australia. Participants: Patients in all Victorian ICUs and all critically ill patients transferred between Victorian hospitals from 27 June to 6 September 2020. Main outcome measure: Acute interhospital transfer of one or more critically ill patients per day from one site to an ICU in another hospital. Results: 150 patients were transported over 61 days from 29 hospitals (64%). ICU Activity Index scores were higher on days when critical care transfers occurred (median, 1.0 [IQR, 0.4-1.7] v 0.6 [IQR, 0.3-1.2]; P < 0.001). Transfers were more common on days of higher ICU occupancy, higher numbers of ventilated or COVID-19 patients, and when more critical care staff were unavailable. The highest ICU Activity Index scores were observed at hospitals in north-western Melbourne, where the COVID-19 disease burden was greatest. After adjusting for confounding factors, including occupancy and lack of available ICU staff, a rising ICU Activity Index score was associated with an increased risk of a critical care transfer (odds ratio, 4.10; 95% CI, 2.34-7.18; P < 0.001). Conclusions: The ICU Activity Index appeared to be a valid marker of ICU strain during the COVID-19 pandemic. It may be useful as a real-time clinical indicator of ICU activity and predict the need for redistribution of critical ill patients.

Sick leave accessibility in junior doctors at an Australian health service.

BACKGROUND: Doctors commonly continue to work when they are unwell. This norm is increasingly problematic during the COVID-19 (SARS-CoV-2) pandemic when effective infection control measures are of paramount importance. This study investigates the barriers existing before COVID-19 that prevent junior doctors with an acute respiratory illness working in Canberra, Australia, from taking sick leave, and offers suggestions about how to make sick leave more accessible for junior doctors. METHODS: Anonymous online survey study. RESULTS: 192 junior doctors were invited to participate in the study. Fifty-four responded, and only those who had worked whilst unwell with an acute respiratory illness were included, providing a total number of fifty responses. Of these, 72% believed they were infectious at the time they worked whilst unwell. 86% of respondents did not feel supported by the workplace to take sick leave when they were unwell, and 96% identified concerns about burdening colleagues with extra workload and lack of available cover as the main deterrents to accessing sick leave. CONCLUSION: Junior doctors at our health service, pre-COVID-19, do not widely feel empowered to take sick leave when they have an acute respiratory illness. Junior doctors are primarily concerned about burdening their colleagues with extra workloads in an environment where they perceive there to be a lack of available cover. Having more available cover, leadership from seniors, and clearer guidelines around the impact of sick leave on registration may contribute to a culture where junior doctors feel supported to access sick leave.

A Dual-Antigen Enzyme-Linked Immunosorbent Assay Allows the Assessment of Severe Acute Respiratory Syndrome Coronavirus 2 Antibody Seroprevalence in a Low-Transmission Setting.

Estimates of seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies have been hampered by inadequate assay sensitivity and specificity. Using an enzyme-linked immunosorbent assay-based approach that combines data about immunoglobulin G responses to both the nucleocapsid and spike receptor binding domain antigens, we show that excellent sensitivity and specificity can be achieved. We used this assay to assess the frequency of virus-specific antibodies in a cohort of elective surgery patients in Australia and estimated seroprevalence in Australia to be 0.28% (95% Confidence Interval, 0-1.15%). These data confirm the low level of transmission of SARS-CoV-2 in Australia before July 2020 and validate the specificity of our assay.

Development of a Mobile Laboratory for Sudden Onset Disasters.

OBJECTIVES: Clinical diagnostics in sudden onset disasters have historically been limited. We set out to design, implement, and evaluate a mobile diagnostic laboratory accompanying a type 2 emergency medical team (EMT) field hospital. METHODS: Available diagnostic platforms were reviewed and selected against in field need. Platforms included HemoCue301/WBC DIFF, i-STAT, BIOFIRE FILMARRAY multiplex rt-PCR, Olympus BX53 microscopy, ABO/Rh grouping, and specific rapid diagnostic tests. This equipment was trialed in Katherine, Australia, and Dili, Timor-Leste. RESULTS: During the initial deployment, an evaluation of FilmArray tests was successful using blood culture identification, gastrointestinal, and respiratory panels. HemoCue301 (n = 20) hemoglobin values were compared on Sysmex XN 550 (r = 0.94). HemoCue WBC DIFF had some variation, dependent on the cell, when compared with Sysmex XN 550 (r = 0.88-0.16). i-STAT showed nonsignificant differences against Vitros 250. Further evaluation of FilmArray in Dili, Timor-Leste, diagnosed 117 pathogens on 168 FilmArray pouches, including 25 separate organisms on blood culture and 4 separate cerebrospinal fluid pathogens. CONCLUSION: This mobile laboratory represents a major advance in sudden onset disaster. Setup of the service was quick (< 24 hr) and transport to site rapid. Future deployment in fragmented health systems after sudden onset disasters with EMT2 will now allow broader diagnostic capability.

Two carbapenemase-producing Enterobacteriaceae outbreaks detected retrospectively by whole-genome sequencing at an Australian tertiary hospital.

In 2014, two genetically-linked cases of carbapenemase-producing Enterobacteriaceae (CPE) were detected at the Canberra Hospital (TCH), prompting an investigation and response that appeared to contain transmission. We report a 2017 retrospective investigation into cases of CPE in the Australian Capital Territory (ACT) that aimed to identify clusters and transmission mechanisms. Cases detected between 2012 and 2016 were identified from the hospital laboratory information system. Whole-genome sequencing (WGS) was performed retrospectively on stored isolates. Seventy-two cases were identified, with nearly 90% of isolates containing blaIMP genes. Using multilocus sequence type (ST) data, we identified two small outbreaks of CPE containing blaIMP-4 (Enterobacter cloacae complex ST24, n = 7; Citrobacter freundii ST8, n = 10), each spanning over three years. Epidemiological and environmental evidence implicate environmental reservoirs and carriers undetected by routine infection prevention and control investigations.

Hospital-acquired influenza in an Australian tertiary Centre 2017: a surveillance based study.

BACKGROUND: In 2017, Australia experienced its highest levels of influenza virus activity since the 2009 pandemic. This allowed detailed comparison of the characteristics of patients with community and hospital-acquired influenza, and infection control factors that contributed to influenza spread. METHODS: A surveillance based study was conducted on hospitalised patients with laboratory-confirmed influenza at the Canberra Hospital during April-October 2017. Differences between the hospital-acquired and community-acquired patient characteristics and outcomes were assessed by univariate analysis. Epidemiologic curves were developed and cluster distribution within the hospital was determined. RESULTS: Two hundred and ninety-two patients were included in the study. Twenty-eight (9.6%) acquired influenza in hospital, representing a higher proportion than any of the previous 5 years (range 0.9-5.8%). These patients were more likely to have influenza A (p = 0.021), had higher rates of diabetes (p = 0.015), malignancy (p = 0.046) and chronic liver disease (p = 0.043). Patients acquiring influenza in hospital met clinical criteria for influenza like illness in 25% of cases, compared with 64.4% for community-acquired cases (p < 0.001). Hospital-acquired influenza cases occurred in two distinct clusters. Patients were moved an average of 5 times after diagnosis. Mean length of stay following diagnosis was 13 days compared to 5 days for community-acquired cases (p < 0.001). Of the patients with hospital-acquired influenza, 22 were in shared rooms during their incubation period and 9 were not isolated in single rooms following diagnosis. Treatment was initiated within the recommended 48 h period following symptom onset for 62.5% of hospital-acquired cases compared with 39.8% of community-acquired cases (p = 0.033). CONCLUSIONS: Our results show that clinical presentation differed between patients with hospital-acquired influenza compared with those who acquired influenza in the community. Cases occurred in two clusters suggesting intra-hospital transmission rather than random importation from the community, highlighting the importance of infection control measures to limit influenza spread. Patients with hospital-acquired influenza may present without classical features of an influenza-like illness and this should promote earlier diagnostic testing and isolation to limit spread. Movement of patients after diagnosis is likely to facilitate spread within the hospital.

Vancomycin-resistant Enterococcus (VRE) outbreak in a neonatal intensive care unit and special care nursery at a tertiary-care hospital in Australia-A retrospective case-control study.

OBJECTIVE: We investigated the risk factors and origins of the first known occurrence of VRE colonization in the neonatal intensive care unit (NICU) at the Canberra Hospital. DESIGN: A retrospective case-control study. SETTING: A 21-bed neonatal intensive care unit (NICU) and a 15-bed special care nursey (SCN) in a tertiary-care adult and pediatric hospital in Australia. PATIENTS: All patients admitted to the NICU and SCN over the outbreak period: January-May 2017. Of these, 14 were colonized with vancomycin-resistant Enterococcus (VRE) and 77 were noncolonized. METHODS: Demographic and clinical variables of cases and controls were compared to evaluate potential risk factors for VRE colonization. Whole-genome sequencing of the VRE isolates was used to determine the origin of the outbreak strain. RESULTS: Swift implementation of wide-ranging infection control measures brought the outbreak under control. Multivariate logistic regression revealed a strong association between early gestational age and VRE colonization (odds ratio [OR], 3.68; 95% confidence interval [CI], 1.94-7.00). Whole-genome sequencing showed the isolates to be highly clonal Enterococcus faecium ST1421 harboring a vanA gene and to be closely related to other ST1421 previously sequenced from the Canberra Hospital and the Australian Capital Territory. CONCLUSION: The colonization of NICU patients was with a highly successful clone endemic to the Canberra Hospital likely introduced into the NICU environment from other wards, with subsequent cross-contamination spreading among the neonate patients. Use of routine surveillance screening may have identified colonization at an earlier stage and have now been implemented on a 6-monthly schedule.

Management of Diabetic Surgical Patients in a Deployed Field Hospital: A Model for Acute Non-Communicable Disease Care in Disaster.

Sudden onset disasters (SODs) have affected over 1.5 billion of the world's population in the past decade. During the same time, developing nations have faced a sustained increase in the burden of non-communicable disease (NCD) with extra pressure placed on health systems. The combined increase in SODs and the NCD epidemic facing the world's most disaster-prone nations will present new challenges to emergency medical teams (EMTs) during disaster response. This report details the experience as an EMT during the Typhoon Haiyan disaster of 2013, with particular reference to the challenges of diabetic management in a surgical field hospital. The incidence of diabetes in this surgical cohort exceeded that of the population by a factor of four. The steps to prepare for and treat diabetes in the field provide a useful model for the management of NCD in the deployed field hospital environment after a disaster. McDermott KM , Hardstaff RM , Alpen S , Read DJ , Coatsworth NR . Management of diabetic surgical patients in a deployed field hospital: a model for acute non-communicable disease care in disaster. Prehosp Disaster Med. 2017;32(6):657-661.

Case report: Sporotrichosis from the Northern Territory of Australia.

We report three cases of lymphocutaneous infection caused by the thermally dimorphic fungus, Sporothrix schenckii from Australia's tropical Northern Territory. Two cases were acquired locally, making them the first to be reported from this region. All three cases presented with ulceration in the limb; however, the classical sporotrichoid spread was present only in the first two cases. Their occurrence within several weeks of each other was suggestive of a common source of environmental contamination such as hay used as garden mulch. Diagnoses were delayed in each case, with each patient having substantial exposure to ineffective antibiotics before the correct diagnosis was made. These cases bring the total number of reported sporotrichosis cases in Australia since 1951 to 199. Lessons from these cases are to consider the diagnosis of sporotrichosis in lesions of typical appearance, even in geographical settings from where this pathogen has not previously been reported.

Tuberculosis: experience in a low endemic area Australian tertiary hospital.

BACKGROUND: Abdominal tuberculosis (ATB) poses a significant diagnostic, management, and resource challenge. In Australia, an increasing number of tuberculosis (TB) cases are being reported, and we describe our experience of ATB in an Australian tertiary institution. METHODS: All diagnosed cases of tuberculosis (TB) at the Royal North Shore tertiary hospital campus of the University of Sydney are entered prospectively into a central registry. Cases of ATB encountered between September 1991 and November 2011 were identified and retrospectively reviewed. RESULTS: In all, 841 cases of TB were identified, of which 20 were abdominal (2.4 %). Median age at presentation was 34 years (range: 22-79 years), and 55 % of patients were women. None of the patients were born in Australia and 11 patients were of South Asian origin. The most common presenting symptom was abdominal pain (65 %). Diagnosis was based primarily on histology (90 % sensitivity), and the sensitivity of PCR analysis in this series was low (44 %). Eleven of the patients required laparoscopy or laparotomy. 40 % of cases involved the peritoneum, and disease was also seen in solid organs (liver, spleen, pancreas, adrenal gland) and bowel (esophagus, small bowel, colon). CONCLUSIONS: In our local experience ATB was seen exclusively in the immigrant population. The presentation of ATB varies greatly, necessitating a high index of suspicion within the context of abdominal symptoms in high-risk groups. The role of surgical involvement is indispensable for both diagnosis and management of ATB-related complications. Surgeons should remain mindful of the diagnosis in an age of increasing worldwide incidence.

Day-to-day variability of oscillatory impedance and spirometry in asthma and COPD.

Variability in airway function may be a marker of disease activity in COPD and asthma. The aim was to determine the effects of repeatability and airway obstruction on day-to-day variability in respiratory system resistance (Rrs) and reactance (Xrs) measured by forced oscillation technique (FOT). Three groups of 10 subjects; normals, stable asthmatic and stable COPD subjects underwent daily FOT recordings for 7 days. Mean total and inspiratory Rrs and Xrs, and expiratory flow limitation (EFL) Index (inspiratory - expiratory Xrs), were calculated. The ICC's were high for all parameters in all groups. Repeatability, in terms of absolute units, correlated with airway obstruction and was therefore lowest in COPD. Day-to-day variability was due mostly to repeatability, with a small contribution from the mean value for some parameters. FOT measures are highly repeatable in health, stable asthma and COPD in relation to the wide range of measures between subjects. For home monitoring in asthma and COPD, either the coefficient of variation or individualized SDs could be used to define day-to-day variability.