Infectious diseases

Objective: To determine the increase in intensive care unit (ICU) bed availability that would result from the use of the New South Wales and Ontario Health Plan for an Influenza Pandemic (OHPIP) triage protocols.Design, setting and patients: Prospective evaluation study conducted in eight Australian, adult, general ICUs, between September 2009 and May 2010. All patients who were admitted to the ICU, excluding ...

on behalf of the Influenza Pandemic ICU Triage (iPIT) Study Investigators

To the Editor: A 38-year-old HIV-positive Somalian refugee with a past history of pulmonary tuberculosis (TB) and poor compliance with antiretroviral therapy (ART) presented with fever, lethargy and mediastinal lymphadenopathy. He was diagnosed with fully drug-sensitive lymph node TB. The CD4 lymphocyte count at TB diagnosis was 20/µL (reference interval, 350–2630/µL), and the HIV RNA viral load was 99 000 copies/µL. Standard anti-TB treatment was commenced, and ART ...

Sarah L McGuinness · Joseph S Doyle · Alan C Street

To the Editor: National disclosure of health care-associated infections has recently been facilitated by the launch of the MyHospitals website by the Australian Institute of Health and Welfare (http://www.myhospitals. gov.au). As high rates of Staphylococcus aureus bacteraemia (SAB) have been reported at our tertiary health care facility,1 we wish to outline the pitfalls and potential misrepresentation of generic health care infection surveillance data when used ...

Leon J Worth · Karin A Thursky · Monica A Slavin

To the Editor: Rates of health care-associated Staphylococcus aureus bacteraemia (HCA-SAB) and hand hygiene (HH) compliance are now subject to public disclosure on the MyHospitals website (http://www.myhospitals.gov.au). HH compliance and HH alcohol hand rub and liquid soap procurement have been associated with reduced methicillin-resistant (but not methicillin-sensitive) S. aureus bacteraemias, generally in the presence of other co-interventions.1,2 However, the National Hand Hygiene Initiative advocates that ...

E Geoffrey Playford · David McDougall · Mary-Louise McLaws

Objectives: To document the prevalence of Chlamydia trachomatis and Neisseria gonorrhoeae in the refugee population settling in Western Australia from 1 January 2006 to 31 December 2009 and make recommendations for future screening for chlamydia and gonorrhoea in the refugee population.Design and participants: A prevalence and quality assurance study of 2610 refugees aged 15 years and older who attended the Humanitarian Entrant Health Service in Western Australia ...

Veronica C Hoad MB BS, MPH · Aesen Thambiran MB BS, FRACGP

To the Editor: Recent studies have highlighted the safety of administering influenza vaccine derived from embryonated chicken eggs to egg-allergic individuals,1-3 as long as the vaccine contains no more than 1 g of egg ovalbumin per dose. This is reflected in recommendations by expert advisory groups including the Australasian Society of Clinical Immunology and Allergy.4 These recommendations have been strengthened by further evidence of the safety ...

Raymond J Mullins · Michael S Gold

Objective: To review patients with severe bilateral vestibular loss associated with gentamicin treatment in hospital. Design and setting: A retrospective case series of presentations to a balance disorders clinic between 1988 and 2010. Main outcome measures: Relationship between vestibulotoxicity and gentamicin dose or dosing profile; indications for prescribing gentamicin. Results: 103 patients (age, 18–84 years; mean, 64 years) presented with imbalance, oscillopsia or both, but none had vertigo. Only three noted some hearing impairment after having gentamicin, but audiometric thresholds for all patients were consistent with their age. In all patients, the following tests gave positive results: a bilateral clinical head-impulse test, a vertical head-shaking test for vertical oscillopsia, and a foam Romberg test. In 21 patients, imbalance occurred during gentamicin treatment (ignored or dismissed by prescribers in 20) and in 66 after treatment; the remaining 16 could not recall when symptoms were first noticed, except that it was after gentamicin treatment in hospital. Total gentamicin dose range was 2–318 mg/kg (mean, 52 mg/kg), daily dose range was 1.5–5.6 mg/kg (mean, 3.5 mg/kg), and duration was 1–80 days (mean, 17 days). Six patients had only a single dose; 26 had five or fewer doses. Serum gentamicin levels, measured in 82 patients, were in the recommended range in 59. Time to diagnosis ranged from 4 days to 15 years. Nephrotoxicity developed in 43 patients. Gentamicin dosage complied with contemporary or current Australian antibiotic guidelines in under half the patients. Conclusions: Gentamicin ototoxicity is vestibular, not cochlear, producing permanent loss of balance, but not of hearing. Gentamicin can be vestibulotoxic in any dose, in any regimen, at any serum level.

Rebekah M Ahmed MB BS, FRACP · Imelda P Hannigan RN · Hamish G MacDougall PhD · Raymond C Chan MB BS, FRACP, FRCPA · G Michael Halmagyi MD, FRACP

Objective: To determine the risk and timing of a broad range of infective outcomes and mortality after splenectomy.Design, setting and participants: Analysis of a non-identifiable linked hospital discharge administrative dataset for splenectomy cases between July 1998 and December 2006 in Victoria, Australia.Main outcome measures: Age, sex, indication for splenectomy, infectious events ...

Claire Dendle MB BS, FRACP, GCHPE · Vijaya Sundararajan MD, MPH, FACP · Tim Spelman MB BS, BSc, GradCert(Stats) · Damien Jolley MSv(Epi), MSc(Stats) · Ian Woolley MB BS, FRACP, DTMH

Further studies are needed to develop evidence-based recommendations for vaccinations and prophylactic antibiotic regimensThroughout the ages, the function of the spleen was subject to much conjecture. It was variously thought to be both the centre of melancholy by the French and the centre for anger by the English (“to vent one’s spleen”). Of no doubt ...

David F M Looke FRACP, FRCPA, MMedSci · Naomi J Runnegar MB BS, FRACP, FRCPA

Objective: To determine the geographical, epidemiological and clinical features of sporotrichosis (a cutaneous fungal infection caused by Sporothrix schenckii) in the New South Wales mid-north coast.Design and setting: We undertook a retrospective case review of S. schenckii infections that occurred during the period 2000–2010. Microbiology laboratory staff and medical practitioners in ...

Shobini Sivagnanam BSc(Med), MB BS · Aiveen M Bannan MB BS, FRACP, MPH · Sharon C-A Chen FRACP, FRCPA, PhD · Anna P Ralph MB BS, FRACP, PhD

To the Editor: Extensive rainfall in Queensland from December 2010 to January 2011 led to much of the state being declared a disaster zone. We report on a cluster of patients requiring hospitalisation with an acute febrile illness after exposure to floodwater in Central Queensland. During the height of the flood emergency, four adults (23–56 years of age) from ...

Hugh Wright · Katie Goot · Benjamin Rogers

To the Editor: The HIV epidemic in Australia is changing. The number of new infections attributed to heterosexual contact has increased, and people from culturally and linguistically diverse (CALD) backgrounds account for a significant proportion of these diagnoses. In the period 2005–2009, 41% of new HIV diagnoses linked to heterosexual transmission were in people from ...

Augustine D Asante · Henrike Körner

A 46-year-old woman, who had lived in rural Australia as a child, presented with abdominal distension, jaundice and cachexia. Abdominal computed tomography showed extensive cystic disease of the liver, peritoneum, ovaries and uterus; well circumscribed coarsely calcified cysts were visible in the abdomen and pelvis (Figure A). Results of hydatid serological testing were consistent with ...

Melanie C Figtree · Matthew R Watts · Robyn Timmins · Ross Smith · Bernard J Hudson

To the Editor: Vertical transmission of Toxoplasma gondii can result in significant morbidity in the fetus and newborn, although it is rare in Australia.1 Antenatal testing has shown seroprevalence of 23%–35%,2,3 which is possibly lower ...

Jude C Jayamaha · Peter Robertson · William D Rawlinson

To the Editor: Strongyloidosis in Australia has been reported in Indigenous Australians, war veterans who have served in South-East Asia and travellers and immigrants from regions in which strongyloidosis is endemic.1,2 The condition is caused by ...

Hannah M Soulsby · Saliya Hewagama · Stephen Brady

To the Editor: I have read two recent reports on neurocysticercosis in the Journal.1,2 After performing a literature search for Australian cases of neurocysticercosis (PubMed search, using the terms “cysticercosis”, “neurocysticercosis” and “Australia”), I found reports of 39 patients, and the reports of 33 of these patients were published in the past two decades. This suggests that the prevalence of neurocysticercosis in Australia is rising, or that it has been increasingly recognised and reported in recent years. As expected in a developed country, more than three-quarters of the patients were immigrants from neurocysticercosis endemic areas, and the remainder were Australian residents who had travelled to endemic regions. So, although it appears that Australia is free of locally acquired neurocysticercosis, it is possible that some immigrants who developed the disease while living in Australia were not infected overseas, because some of them developed the disease more than 10 years after they migrated from their home countries. The occurrence of neurocysticercosis among people returning from endemic areas to cysticercosis-free countries shows that cysticerci may remain asymptomatic for a long time in the nervous system or may become symptomatic years (or even decades) after infection.3 Indeed, certain forms of neurocysticercosis, including calcifications, chronic arachnoiditis, subarachnoid cysts and even spinal cysticerci may manifest a long time after infection. However, the single cysticercus granuloma causes symptomatic disease in the first few months after infection;4 this form of the disease occurs mainly in people who have not had previous infection and involves an acute inflammatory reaction to the implantation of one cysticercus in the brain parenchyma. At least seven of the immigrants to Australia with neurocysticercosis had this form of the disease, and some of them developed symptoms up to 3 years after arrival, suggesting local acquisition of the disease from a contact infected with Taenia solium. Unfortunately, case reports and case series of neurocysticercosis diagnosed in Australia do not include information on whether household contacts of diagnosed patients had been tested for carriage of Taenia. Increased awareness of the mechanisms of disease transmission for neurocysticercosis will help to reduce further spread of this zoonosis.

Oscar H Del Brutto

Veterinary pharmacologist Stephen Page believes that antibiotic use in animals benefits human and animal health While antibiotic use in livestock has the potential to cause harm to human health, the likelihood of harm arising from the use of antibiotics under current Australian practices is highly unlikely. There is ample independent evidence supporting the long history of appropriate use of antibiotics in Australian livestock. For example, the past six annual reports of the National Residue Survey contain the results of tests for the presence of up to 38 antibacterial agents in the edible tissues of cattle, pigs, poultry and sheep.1 Almost 400 000 assays were performed and compliance with Australian standards was at or above 99.99% for each of the four species tested. Given the high morbidity and mortality associated with many of the diseases of livestock (eg, necrotic enteritis and coccidiosis in poultry, bovine respiratory disease and mastitis in cattle, and post-weaning diarrhoea and porcine respiratory disease in pigs), prevention of infectious diseases is of fundamental importance. Judicious use of antibiotics in integrated animal health plans has an important role to play in protecting the health and welfare of animals and in contributing to the safety and quality of the food that is produced. Only 39 antibacterial agents are approved and available for use in Australian livestock, six of which are from classes with no human medical use counterpart. As an example of contemporary patterns of use, a recent survey of the use of antimicrobial agents in the Australian pig industry found most use was for control of infections with Lawsonia intracellularis, Mycoplasma hyopneumoniae and Escherichia coli and relied on sulfonamides, tetracyclines and penicillins2 — all drugs considered by the Expert Advisory Group on Antimicrobial Resistance to be of low importance to public health.3 What led the Australian Department of Health and Ageing to conclude that “Australia’s food supply is one of the safest and cleanest in the world”4? In 2008, Food Science Australia was commissioned to survey the presence of bacteria with antimicrobial resistance in samples of raw whole poultry, beef mince and pork chops collected from shops in Melbourne, Sydney, Brisbane and Perth. Among the isolates of Campylobacter jejuni, Salmonella and E. coli that were collected, no fluoroquinolone or ceftiofur resistance was identified. No Enterococcus faecium was isolated and all Enterococcus faecalis isolates were susceptible to ampicillin, penicillin and vancomycin; only one of 300 E. faecalis isolates was resistant to gentamicin. In contrast, Denmark, despite being recognised as having one of the most regulated and conservative approaches to the use of antibiotics in livestock, noted significant antibiotic resistance in their most recent antimicrobial resistance monitoring report: fluoroquinolone-resistant C. jejuni in 17% of broiler meat samples; high-level gentamicin resistance in E. faecalis from pork samples; vancomycin-resistant E. faecium in 47% of isolates from broiler chickens; extended-spectrum β-lactamase producing E. coli (ceftriaxone resistant) in 27% of broiler cloacal swabs and 9% of broiler meat samples; fluoroquinolone-resistant Salmonella enterica subspecies enterica serovar Enteritidis in 8% of sporadic cases of human salmonellosis; multiresistant Salmonella enterica subspecies enterica serovar Typhimurium definitive type 104 (DT104) in 7% of isolates from pigs; and ceftiofur-resistant E. coli in 1% of domestic pork and broiler meat samples.5 OzFoodNet (http://www.ozfoodnet.gov.au) was established by the Australian Government in 2000 to enhance surveillance of foodborne disease. It has published eight annual reports, which do not identify any cases of domestically acquired foodborne illness caused by infections with Salmonella, Campylobacter or Shiga toxin-producing E. coli complicated by antibiotic resistance of livestock origin. By contrast, a number of human cases of fluoroquinolone-resistant Campylobacter infection and S. Typhimurium DT104 infection have been described, but each originated from overseas (especially South-East Asia) or from imported food. Since 2001, the Australian Salmonella Reference Centre has tested more than 18 000 Salmonella isolates from cattle, pigs, sheep, chickens (broilers and layers), raw meat and eggs. No fluoroquinolone-resistant isolates were found and only nine isolates (most of which were submitted before 2004) were phenotypically resistant to cefotaxime at 1 g/mL. Australians should be reassured that food safety is the highest priority in livestock production. The Australian Veterinary Association is currently updating a series of guidelines for responsible use of antibiotics, the poultry industry is supporting leading edge research to develop a vaccine to prevent necrotic enteritis, and the pig industry has spent over $7 million on projects to refine and replace the use antibiotics and has committed to halving antibiotic use by 2018. Antibiotics used prudently and selectively can clearly benefit animal health and welfare, leading to overall human health benefits, not risks.

Stephen W Page BVSc(Hons), MVetClinStud, MAppSci(EnvTox)

Restoration of immune responses against opportunistic pathogens after commencing antiretroviral therapy (ART) may cause immune restoration disease (IRD) in about 10%–40% of HIV patients with low CD4+ T-cell counts and usually presents clinically as a type of immune reconstitution inflammatory syndrome (IRIS). IRIS may be associated ...

Martyn A H French MD, FRACP, FRCPath

Objectives: To explore the burden of illness associated with infectious syndromes and to measure the associated use of antimicrobials in residential aged care facilities (RACFs).Design, setting and subjects: Retrospective analysis of data for January 2006 to December 2010 from an infection surveillance system covering residents of four co-located RACFs, with a total of 150 residential care beds, in Melbourne, Victoria.Main outcome measures: Number of episodes and incidence of health care-associated infection (HCAI); rate of antimicrobial use; prescribing concordance with McGeer criteria for infection; frequency of clinical specimen collection.Results: There were 1114 episodes of an infectious syndrome over 267 684 occupied bed-days (OBD), affording an average HCAI rate of 4.16 episodes/1000 OBD annually over 5 years (95% CI, 3.92–4.41). The mean rate of antimicrobial use was 7.07 courses/1000 OBD (range, 6.71–7.84). Around 40% of antimicrobial prescribing was for episodes that did not fulfil the McGeer criteria for clinical infection; this included about half of suspected urinary tract and upper respiratory tract infections (URTI), and about one-third of suspected lower respiratory tract and skin infections. Antimicrobials were routinely prescribed for URTI and bronchitis. Of all episodes treated with antimicrobials, 36% had documentation that a clinical specimen was obtained.Conclusions: The HCAI rate remained relatively stable over time. Routine surveillance and feedback of infection rates to the facilities did not result in a noticeable decrease of infection burden over time. It is of immediate concern that antimicrobials were being prescribed for a large proportion of suspected infections that did not meet criteria for clinical infection. Opportunities exist to further improve the use of antimicrobials in the RACF setting.

Ching Jou Lim BPharm(Hons) · Susan C McLellan RN, GradCert InfectControl, GradDipNSInfectControl · Allen C Cheng FRACP, MPH, PhD · Joanne M Culton RN, GradCert InfectControl · Sneha N Parikh BA · Anton Y Peleg* MB BS, PhD, FRACP · David C M Kong* BPharm, MPharm, PhD

Objectives: To determine incidence and trends in antibiotic resistance in Australian Salmonella enterica subspecies enterica serovars Typhi (S. Typhi) and Paratyphi (S. Paratyphi) isolates over the past 26 years.Design: A retrospective analysis of consecutive microbiologically confirmed enteric fever isolates.Participants and setting: All S. Typhi and S. Paratyphi isolates from patients diagnosed with enteric fever in Australia between 1985 and 2010.Main outcome measures: Incidence and variation in antibiotic resistance over time and according to country of origin.Results: We analysed 2551 isolates, which originated from 74 countries or regions, mainly India (33%) and Indonesia (22%). The incidence among Australian residents increased from four to five before 2003 to seven cases per million person-years after 2003. Multidrug resistance (chloramphenicol, ampicillin, trimethoprim) and nalidixic acid resistance emerged rapidly from the early 1990s, with nalidixic acid resistance increasing to 70% in 2009–2010, while multidrug resistance was relatively stable at between 4% and 11%. Nalidixic acid and multidrug resistance rates are highest in isolates from the Indian subcontinent. Some countries in South-East Asia, such as Indonesia, had very low rates of resistance; however, this varied across the region.Conclusions: Nalidixic acid resistance has become widespread in enteric fever isolates from the Indian subcontinent and some parts of South-East Asia, justifying the use of ceftriaxone or azithromycin rather than ciprofloxacin as first-line treatment. However, resistance in some countries remains rare, potentially allowing treatment to be adjusted according to country of origin.

Robert J Commons MB BS, BMedSci, DipObsGyn · Emma McBryde MB BS, FRACP, PhD · Mary Valcanis BSc, MPH · Joan Powling BAgrSc · Alan Street MB BS, FRACP · Geoff Hogg BM, BS, FRACP