Strongyloidiasis: a case for notification in Australia?

To the Editor: Australia’s National Notifiable Diseases Surveillance System (NNDSS) is used to monitor trends in 58 communicable diseases or conditions. The incidence of notifiable diseases can be decreased by public health action. Some diseases require rapid local responses, such as outbreaks of vaccine-preventable or foodborne diseases. Upward trends in the incidence of other notifiable diseases — for example, tuberculosis, sexually transmitted infections and bloodborne viruses — can be managed by less-rapid responses. The NNDSS exists not for data collection per se, but for public health action.

The NNDSS is a dynamic tool of great value in specific diseases, particularly when control or elimination programs are being implemented, such as for hydatid disease, polio and measles. Diseases and conditions can be added or removed as required by the need for public health action.

Currently, Aboriginal people in rural and remote communities have a very high prevalence of strongyloidiasis, a lifelong disease caused by infection with the gastrointestinal nematode Strongyloides stercoralis.1 This parasite is very rare in mainstream Australian communities and is generally acquired overseas or from outback Indigenous communities. Prevalence in many Indigenous communities is 15% or greater, and laboratory records indicate that the infection is widespread in Indigenous communities in Queensland, the Northern Territory, Western Australia, northern South Australia and northern New South Wales.2,3 However, the epidemiological picture is patchy because data are not routinely collected.4,5 Management of individual Indigenous patients appears to be inadequate — many do not receive appropriate treatment, with potentially fatal consequences.5 A recent systematic literature review of strongyloidiasis in Indigenous Australians highlighted lack of data as one of the major barriers to controlling and eliminating the disease.5 Strongyloidiasis can be easily and cheaply cured by oral ivermectin at individual patient and community levels.1

We urge the Australian Government Department of Health to consider placing strongyloidiasis on the NNDSS, in order to establish an accurate estimate of incidence that will inform the necessary public health action at community, regional and national levels. We propose that all reported cases be laboratory confirmed, based on faecal examination or serology.6,7 These data can be collated and used to guide implementation of a national strongyloidiasis elimination program.

[Correspondence] A premature mortality target for the SDG for health is ageist

Ole Norheim and colleagues’ Article (Jan 17, p 239)1 provides a robust empirical study of the effects of a reduction in mortality in people younger than 70 years. Although this analysis is itself perfectly valid, the ethical principles on which it is based are deeply troubling. Specifically, the concept of premature mortality—which has come to the fore in debates about non-communicable diseases and about the 2030 Sustainable Development Goals (SDGs)—has the potential to undermine the cherished, fundamental principle of health as a universal right for all.

[Correspondence] A premature mortality target for the SDG for health is ageist – Authors’ reply

The Millennium Development Goals (MDGs) for health, adopted in 2000, targeted substantial reductions by 2015 in a few MDG-selected causes: mortality in children younger than 5 years, maternal mortality, and mortality from HIV, tuberculosis, and malaria. The World Health Assembly resolution on non-communicable diseases (NCDs), adopted in 2012, targeted a 25% reduction from 2008 to 2025 in NCD mortality at ages 30–69 years.1

Why the measles vaccine works for life

A new study has found the reason why measles only needs a two-dose vaccine in childhood to provide immunity for life.

The study, published in Cell Reports, has found that while influenza mutates regularly, the surface proteins the measles virus uses to enter cells are ineffective if they suffer a mutation. Therefore any changes to the virus would come at a great cost.

The researchers mutated all the genes in a virus using a high-throughput approach. They inserted the mutations across the measles genome and looked to see whether the viruses were still incapable of infection.

Unlike the influenza virus, measles could not tolerate any mutations to the proteins that are recognised by the human immune system.

Senior study author Nicholas Heaton, a microbiologist at the Icahn School of Medicine at Mount Sinai, New York said they didn’t expect such results.

“The almost complete lack of tolerance to insertional mutation of the measles proteins was surprising. We thought that they may be less tolerant than the influenza proteins, but we were surprised by the magnitude of the difference,” he said.

Heaton says they don’t yet know why the measles virus would find an evolutionary advantage to being so rigid.

“If we can better understand why flexibility or rigidity is imposed at a molecular level, we may be able to understand more about why we see different dynamics of viral evolution.”

Budget breakdowns

Organ and Tissue Donation

Despite programs to encourage more donors there has been a decline in the rate of organ donations over the past two years according to ShareLife.

The Australian Government hope to improve organ and tissue donation rates by providing $10.2 million over the next two years. The funding will go towards delivering clinical education to hospitals, developing a new Australian Organ Matching System and enhancing the Australian Organ Donor Register.

Currently around 1500 people are on Australian organ transplant waiting lists at any time. One organ and tissue donor can transform the lives of 10 or more people.

The Government will also continue to provide minimum wage for up to nine week to employers of people who have taken leave to donate organs as part of the Supporting Leave for Living Organ Donors Programme. The aim of the Programme is to help alleviate the financial stress that can be experienced by living organ donors by reimbursing employers for payments or leave credits provided to their employees for leave taken to donate an organ and recover from the procedure. The Government announced that the Programme will continue for the next two years.

Tropical health

The Government will provide $15.3 million over four years to invest in research into exotic disease threats to Australia and the region.

The National Health and Medical Research Council will receive 6.8 million to support research into tropical diseases, build collaboration and capacity in the health and medical research workforce, and promote the translation of this research into health policy and practice.

The Government will also provide $8.5 million to establish an Australian Tropical medicine Commercialisation grants program to support Australian researchers to commercialise therapeutics and diagnostics in tropical medicine.

National Drugs Campaign

The Government will provide $20 million over two years to renew the National Drugs Campaign. The Campaign aims to reduce young Australians’ motivation to use illicit drugs by increasing their knowledge about the potential negative consequences of drug use. It is a media campaign to promote the avoidance and cessation of illicit drug use.

The campaign will focus on raising awareness to young people and their parents about the harm caused by illicit drug use, in particular methamphetamine also known as ice.

Royal Flying Doctor Service

The Government has committed additional funding to support the Royal Flying Doctors Service to deliver emergency and primary health care services to people in rural and remote communities of Australia.

The Service will receive an extra $20 million as part of the Government’s commitment to rural and remote communities.

Kirsty Waterford

Cytomegalovirus disease in immunocompetent adults

To the Editor: We read with interest the review by Lancini and colleagues on cytomegalovirus (CMV) in immunocompetent patients.1 This topic and its associations with ocular disease has garnered increased recognition in the eye care community.

Clinically, CMV can cause an anterior uveitis (iritis) or, more rarely, retinitis, in otherwise healthy patients.2 The uveitis typically features a chronic and/or recurrent course with anterior segment inflammation, keratic precipitates, endotheliitis, iris atrophy and elevated intraocular pressure (IOP).3 CMV retinitis is characterised by confluent or semiconfluent areas of retinal whitening with haemorrhage.4

As with systemic CMV disease, oral valganciclovir appears to be effective treatment for ocular disease.3–5 CMV-associated ocular disease in immunocompetent adults is underdiagnosed due to low clinical suspicion and its capacity to mimic inflammatory eye disease associated with other Herpesviridae such as herpes simplex virus or varicella zoster virus.3,5 Misdiagnosis as other Herpesviridae can result in antiviral treatment that is ineffective in CMV disease. Thus, CMV ocular disease should be considered as a differential diagnosis in immunocompetent patients presenting with chronic unilateral anterior uveitis or retinitis. Where suspected, an anterior and/or vitreous chamber paracentesis with viral polymerase chain reaction (PCR) analysis should be performed for definitive diagnosis.3

A recent case illustrates this diagnostic challenge. A 53-year-old immunocompetent and systemically well man presented with a unilateral chronic anterior uveitis and elevated IOP. Treatment with topical corticosteroid eyedrops was commenced for non-infectious uveitis. After a poor response, an anterior chamber paracentesis was performed, which tested positive for CMV (on PCR). The uveitis subsequently became quiescent with oral valganciclovir.

Haikerwal departs top World Medical Association position

The international standing of the medical profession is high, with governments around the world regularly seeking the counsel of the World Medical Association and national organisations on health matters, according to outgoing WMA Chair of Council Dr Mukesh Haikerwal.

Dr Haikerwal, who served as WMA Council Chair for four years until losing a run-off for the position last month, said many doctors and other health professionals continued to work in extremely challenging conditions, but their commitment to the welfare of patients meant that the profession was well-respected and influential.

“The profession is highly regarded and its contribution is sought after,” the former AMA President said, though he warned, “a lot of work has to be done to retain that place, with on-going advocacy on the behalf of patients and doctors”.

Dr Haikerwal said one of the most gratifying achievements of his four-year term was the development of the medical profession in Africa, particularly the creation of national medical associations.

He was particularly pleased by the founding of the Zambian Medical Association last year by doctors who had received WMA-sponsored training and support in organisational skills.

“It has now become the go-to organisation for the Parliament of Zambia on health issues, and Zambia is preparing a bid to host the WMA Conference in 2017. They have gone from zero to hero in very quick time,” Dr Haikerwal said. “This is the work that is so gratifying, bringing the medical viewpoint into national debates by building the capacity of organisations.”

But he said there were also disturbing developments, particularly increased violence against doctors and other health professionals.

Dr Haikerwal said increasingly in countries as diverse and China, Turkey, the United States and in Eastern Europe, reduced health spending meant that an increasing proportion of patients were not receiving the care they expected, often resulting in violent – and sometimes fatal – attacks on doctors, nurses and other health workers.

Dr Haikerwal said it had been a great honour to serve as WMA Chair, a position which, coming from Australia, had been “a double-edged sword”.

“It was fantastic, because Australia is so highly regarded across the globe as a voice of reason and creative thinking and not locked into alliances,” he said. “But the negative is that it is a long way to get anywhere.”

Dr Haikerwal has been succeeded by immediate-past American Medical Association President Dr Ardis Hoven, who was elected to become the WMA’s first woman Chair at its 200^th Council meeting in Oslo last month.

Dr Hoven is an internal medicine and infectious disease specialist and a Professor of Medicine at Kentucky University.

“We face complex and far-reaching challenges – shrinking resources, complicated and difficult practice environments, shifting government regulations and dangerous working conditions,” Dr Hoven said. “However, our current work speaks to our impact”.

Dr Haikerwal has joined the Board of mental health organisation beyondblue.

Adrian Rollins

AMA in the News

Your AMA has been active on policy and in the media on a range of issues crucial to making our health system better. Below is a snapshot of recent media coverage.

Print/Online

Medics to fix ‘fear’ culture, The Daily Telegraph, 4 April 2015

A change in the way doctors and nurses report abuse is needed to buck the scourge of sexual harassment and protect whistleblowers within the medical industry. AMA President A/Professor Brian Owler was committed to bringing about cultural change within the profession.

$8.40 more to see doctor, Herald Sun, 7 April 2015

Patients could be paying up to $8.40 for a visit to the doctor by 2018, more than they would have paid under the GP co-payment. AMA President A/Professor Brian Owler said the lazy policy would mean fewer patients would be offered bulk-billing.

Religious belief saw mum and baby die, The Daily Telegraph, 8 April 2015

The AMA has defended doctors at a top Sydney hospital forced to let a heavily pregnant woman and her unborn child die after the mother refused a blood transfusion because she was a Jehovah’s Witness. AMA Vice President Dr Stephen Parnis said doctors could not force a patient to accept treatment.

Not in the script – chemists selling your data, Sunday Mail Adelaide, 12 April 2015

Some chemists are selling their patients’ prescription information to a global health information company, which sells it on to drug firms, trying to boost their sales. AMA Chair of General Practice Dr Brian Morton called it an amazing invasion of privacy for purely commercial reasons.

Coalition’s ‘no jab, no pay’ policy ties benefits to immunisation, Australian Financial Review, 13 April 2015

Australian parents will lose thousands of dollars’ worth of childcare and welfare benefits if they refuse to vaccinate their children. AMA President A/Professor Brian Owler said the AMA backed the plan and said vaccination remained one of the most effective public health measures that we have.

Hospitals ‘storm’ warning, Adelaide Advertiser, 16 April 2015

The number of public hospital beds across Australia has fallen by more than 200 and no State has met emergency department targets. AMA President A/Professor Brian Owler said hospital performance benchmarks are not being met and things will only get worse as funding declines.

AMA hospital report card gives states fuel for fight, The Australian, 16 April 2015

Tony Abbott will face heightened pressure to reverse cuts of $80 billion to health and education, with a snapshot of public hospital performance handing the states fresh ammunition to press home their case. AMA President A/Professor Brian Owler will use the report to warn the Government that its extreme public hospital cuts are unjustified.

Church no longer exempt for jabs, Hobart Mercury, 20 April 2015

A religious exemption loophole, that allowed parents who opposed vaccinations to continue to receive childcare and family tax payments has been scrapped. AMA President A/Professor Brian Owler praised the move.

AMA warns against continued freeze on rebates, ABC News, 22 April 2015

AMA President A/Professor Brian Owler said at a time when the Government should be increasing its investment in general practice, the Medicare rebate freeze will eat away at the viability of individual practices.

Rape row over new anti-jab campaign, Adelaide Advertiser, 23 April 2015

A Facebook graphic on the Australian Vaccination Network site that compares vaccination to rape has been condemned by doctors, the Rape Crisis Centre, and politicians as abhorrent and insulting. AMA President A/Professor Brian Owler said the post undermines the organisation and shows lack of intelligence and common sense.

Doctors back review of Medicare rebates, West Australian, 23 April 2015

Doctors have backed a sweeping review of the Medicare Benefits Schedule, but warned the Federal Government not use it as an excuse to cut patient services. AMA President A/Professor Brian Owler agreed the MBS was outdated and said any savings from the review should be reinvested into the health system.

Aussie in sick new IS video, Sunday Herald Sun, 26 March 2015

The shocking new public face of Islamic State death cult is an Australian doctor. AMA President A/Professor Brian Owler said he was appalled that any medical professional would want to work for terrorists.

Transparency on dug company payments and trips a step closer, The Age, 28 April 2015

Patients will find out what payments and educational trips their doctors have received from drug companies. AMA Chair of General Practice Dr Brian Morton said it was insulting and naïve to suggest doctors would be unduly influenced by a free meal.

Terror doctor free to practise, Adelaide Advertiser, 28 April 2015

The Medical Board is refusing to deregister the former Adelaide doctor who left Australia to join the Islamic State terrorist group. AMA Vice President Dr Stephen Parnis said he expected the Medical Board to look closely at the case from legal and professional standards perspectives.

Scientists call for action on disease risks from climate change, Sydney Morning Herald, 30 April 2015

The Australian Academy of Science has released a report which shows a range of tropical diseases becoming more widespread in Australia due to climate change. AMA President A/Professor Brian Owler said the report should be a catalyst for the Abbott government to show leadership on reducing greenhouse gas emissions and mitigating their effects on health.

Radio

A/Professor Brian Owler, 774 ABC Melbourne, 7 April 2015

AMA President A/Professor Brian Owler talked about the decision to axe the proposed $5 Medicare co-payment in favour of an alternative Government plan to freeze the amount received by doctors in rebates.

Dr Stephen Parnis, 6PR Perth, 13 April 2015

AMA Vice President Dr Stephen Parnis discussed the use of the welfare system to boost immunisation rates. Dr Parnis said in the 1990s the Howard Government also linked immunisation to social security, which resulted in a big increase in vaccination rates.

A/Professor Brian Owler, Radio National, 16 April 2015

AMA President A/Professor Brian Owler discussed Federal funding for health. A/Professor Owler said the health system has never been adequately funded and doctors and nurses have done well to meet a rise in demand.

A/Professor Brian Owler, 2SM Radio, 16 April 2015

AMA President A/Professor Brian Owler talked about the use of paw paw for chronic back pain. A/Professor Owler said paw paw is a well-known treatment, but that people do not tend to use it as much nowadays.

A/Professor Brian Owler, 4BC Brisbane, 16 April 2015

AMA President A/Professor Brian Owler talked about the issue of health funding and the AMA Public Hospital Report Card. A/Professor Owler said the issue is capacity and resources, and that he is concerned about the future given reduced Commonwealth funding.

Dr Stephen Parnis, 2GB Sydney, 23 April 2015

AMA Vice President Dr Stephen Parnis talked about the recent Facebook post from the Australian Vaccination Skeptics Network, which compares forced vaccination to rape. Dr Parnis said the campaign shows how disgraceful and unhinged some anti-vaccination campaigners are.

A/Professor Brian Owler, 2UE Sydney, 28 April 2015

AMA President A/Professor Brian Owler talked about the Medical Board’s handling of the case of an Australian-registered doctor who has joined Islamic State. A/Professor Owler said he understands the Medical Board is working with security agencies to ensure that the public is safe, and to prevent any possibility of Dr Kamleh returning to Australia to continue practising medicine.

A/Professor Brian Owler, ABC NewsRadio, 30 April 2015

The Australian Academy of Science is warning of the impacts of global warming predicting food and water shortages, along with extreme weather events. AMA President A/Professor Brian Owler said climate change has been a political battleground and that Australia is not ready to cope with its impacts.

Television

A/Professor Brian Owler, Channel 9, 16 April 2015

AMA President A/Professor Brian Owler talked about the AMA’s Public Hospital Report Card. A/Professor Owler said many hospitals are not reaching targets in the emergency department treatment and elective surgery wait times.

Dr Stephen Parnis, Channel 9, 12 April 2015

AMA Vice President Dr Stephen Parnis talked about the Government’s announcement that childcare rebate payments will be cut for families who do not vaccinate their children. Dr Parnis said the children involved are innocent, and their futures need to be insured.

A/Professor Brian Owler, ABC News 24, 16 April 2015

AMA President A/Professor Brian Owler discussed the crisis in Australia’s public hospitals as Commonwealth funding is wound back. A/Professor Owler said the Commonwealth are not living up to their responsibilities to fund States and Territories properly to run hospitals.

A/Professor Brian Owler, Channel 9, 22 April 2015

AMA President A/Professor Brian Owler discussed welcoming the plans for a major review of the Medicare Benefits Schedule. A/Professor Owler said the review is clinician-led and is not just about finding savings.

A/Professor Brian Owler, Sky News, 29 April 2015

AMA President A/Professor Brian Owler discussed the future of the public hospital system if Federal Government cuts come into effect. A/Professor Owler said state governments lack the capacity to increase revenue to pick up the slack.

A/Professor Brian Owler, ABC News 24, 30 April 2015

AMA President A/Professor Brian Owler called on the Federal Government to show leadership on climate change or risk the health of Australians. A/Professor Owler said there was overwhelming scientific consensus that the climate is changing and there will be consequences for health.

Listeriosis cluster in Sydney linked to hospital food

Three patients were diagnosed with listeriosis in different hospitals within a short period. Rapid molecular typing techniques and review of hospital menus using an electronic menu database allowed prompt identification of the source of infection and implementation of control measures that prevented further infections.

Clinical record

Between 4 and 12 April 2013, a public health unit in Sydney was notified of three patients in different tertiary hospitals in two local health districts (LHDs) who had tested positive for listeriosis. This unusual occurrence prompted concern that the cases might be linked through contaminated hospital meals because hospitals in these LHDs source food from the same suppliers. The public health unit led a public health investigation, which included representatives from the New South Wales Food Authority, OzFoodNet, two NSW reference laboratories, food services, dietetics services and hospital infection control staff, to determine whether there was a link between the cases.

Listeriosis is a notifiable disease in NSW, and cases are investigated in accordance with NSW Health control guidelines.1All listeriosis notifications in NSW between 2 April (when the first case was detected) and 25 June (70 days after control measures were implemented) were reviewed in the process of case finding. A case was defined as a confirmed diagnosis of listeriosis during this period in any person in NSW who had been an inpatient of a public hospital in the two LHDs at any time during the potential exposure period for listeriosis; ie, 3–70 days prior to symptoms. Food history information was supplemented by records obtained from the electronic menu database (CBORD, Sydney) of the two LHDs, which records all hospital food menu items ordered by patients during their admissions. Positive blood cultures collected from patients underwent molecular subtyping, including binary typing, multiple-locus variable-number tandem repeat analysis (MLVA), pulsed-field gel electrophoresis (PFGE) and molecular serotyping. Food and environmental specimens were screened for Listeria species, including L. monocytogenes, with a multiplex polymerase chain reaction (PCR) assay, and PCR-positive results were reported as presumptive positives and confirmed by culture; isolates from positive samples underwent molecular subtyping.

Only the initial three notified patients met the case definition. Patient 1 was an 82-year-old inpatient of hospital A with a history of heart failure and chronic obstructive pulmonary disease; blood cultures that tested positive for L. monocytogenes were collected on 2 April. Patient 2 was a 34-year-old inpatient of hospital B with myelofibrosis; blood cultures that tested positive for L. monocytogenes were collected on 6 April. Patient 3 was a 71-year-old with end-stage hepatocellular carcinoma and a history of two recent admissions to hospital C, and re-admitted on 8 April after a fall. Blood cultures collected that day were positive for L. monocytogenes. The patient died on 9 April.

Foods known to pose a risk of transmitting listeriosis, as well as food items consumed by all three patients during the overlapping periods of their admissions (20–26 March) were identified from hospital menus. Notable food items are listed in the Box.

The food safety profiles of the companies that manufactured these products were reviewed, and samples from local hospitals were tested on 16 April. There were no concerns about Companies Y and Z. Three weeks earlier, however, an environmental swab from the factory of Company X had tested positive for L. innocua during regular in-house testing, and a chocolate profiterole produced on 2 April had also tested positive for Listeria species; this batch had subsequently been discarded. Data from the menu database showed that all three patients had ordered chocolate profiteroles on 24 March. A leftover chocolate profiterole from the same batch was found in a local hospital and tested. The NSW Food Authority inspected the premises of Company X on 17 April and collected food and environmental samples for testing.

On 18 April, the isolates from the three patients were reported as having identical binary types (223), MLVA profiles (04-17-16-05-03-11-14-00-16) and serotypes (1/2b, possible 3b, 7), and on 15 May they were confirmed to share an identical PFGE pattern (4A : 4 : 1). On 19 April, PCR testing of the chocolate profiterole left over from the batch ordered by the patients on 24 March returned a presumptive positive result for L. monocytogenes, but repeat testing later indicated that this had been a false positive. All other samples of leftover hospital foods were negative for L. monocytogenes. Listeria was detected in seven environmental samples from Company X’s premises, and L. monocytogenes was detected in a further two environmental samples from the production facility; the results of molecular subtyping of one of these samples (binary typing, MLVA and PFGE) were identical with those of the clinical specimens.

Creamy rice pudding was the first high-risk food identified and was temporarily withdrawn from all hospitals in the LHDs on 12 April until all products had been tested for L. monocytogenes. On 16 April, desserts from Company X were withdrawn from all Sydney hospitals in which they were served. By the time of the presumptive positive PCR result, the risk of further infections in those who had consumed profiteroles was regarded as low, and it was decided not to proceed with the resource-intensive task of tracing all 1297 profiteroles served in hospitals within the LHDs on 24 March. Instead, active case finding was initiated by issuing a media release, alerting all treating doctors and general practitioners within the LHDs, and by establishing a public hotline number on 20 April.

Discussion

Listeriosis is an infection caused by L. monocytogenes and is transmitted through the ingestion of contaminated food, aided by the ability of the bacterium to survive some food processing techniques and to multiply at refrigerator temperatures.2,3 Listeriosis usually presents as non-invasive gastroenteritis in immunocompetent individuals, and as more severe invasive disease in older people, the immunocompromised and in pregnant women.2 Hospitalised patients are particularly likely to be older or immunocompromised, as were the patients in this cluster, and are therefore especially susceptible to listeriosis.4

Most cases of listeriosis are apparently sporadic, but foodborne outbreaks occur, and health care-associated listeriosis clusters have occasionally been reported.5,6 As the incubation period is quite long (3–70 days), it is often difficult to identify the vehicle of infection in listeriosis outbreaks.2,6 The increasing application and resolution of molecular subtyping of foodborne bacterial pathogens has, however, enabled investigators to detect clusters and track food sources of infection.7,8

Previous hospital outbreaks have not always identified specific vehicles of transmission,6 and inadequate records of the food items consumed by patients may have contributed to this failure.4 In the outbreak reported here, an electronic menu database enabled rapid identification of potential food sources and investigation of suppliers producing these foods, and prompt implementation of control measures. This would have been almost impossible with a manual menu system. The identification of this cluster led to the relevant services upgrading existing food safety plans to ensure that the future risk of hospital-acquired listeriosis is further minimised.

By identifying a rare and unique strain of L. monocytogenes in all three patients, the laboratory techniques used in this investigation were central to linking the affected patients with a food item produced by Company X. These techniques play an increasingly important role in detecting, investigating and controlling foodborne outbreaks.4,8–10 Binary typing and MLVA are PCR-based, and are the standard methods used in major Australian reference laboratories. Binary typing is rapid, with a turnaround time of 3 hours once DNA has been extracted from L. monocytogenes isolates. Binary type 223 is rare, and has been found in only one of 75 clinical L. monocytogenes food and environmental isolates in NSW since 2010, and in none of the 35 NSW isolates since 2012; its detection was the first indication of a link between the three patients in this report. MLVA has a greater discriminatory power than binary typing, with a turnaround time of 2–3 days; its use in parallel with binary typing was critical for the timely identification of a relationship between the isolates. PFGE is considered to be the gold standard of bacterial molecular typing because of its high discriminatory power. It is, however, time-consuming (requiring 4–5 days), technically demanding and not as portable as PCR-based typing methods. In this outbreak, it provided the confirmatory link between the clinical and environmental isolates.

Chocolate profiteroles were initially identified as the likely vehicle of transmission based on presumptive positive PCR results. PCR methods provide more rapid results than culture-based methods, and this prompted a public alert identifying profiteroles as the contaminated food source. When the PCR result was later deemed a false positive, chocolate profiteroles could no longer be viewed as the definite source of infection. Three further pieces of evidence nevertheless justified the decision to temporarily remove the products of Company X from hospital menus: the matching molecular profiles of isolates from the patients and from environmental samples from Company X; the patients’ food consumption histories; and the detection by Company X of Listeria species in a profiterole produced on 2 April. There were no further infections after this decision was taken.

Rapid molecular subtyping was combined with reviewing an electronic hospital menu database to provide timely microbiological and epidemiological evidence that the three patients in the reported cluster probably acquired their infections from a contaminated hospital dessert produced by Company X. The identification of a likely source of infection and the quickly implemented control measures probably prevented further cases. This cluster of infections highlights the need for vigilant regulation and approval processes for food suppliers who service hospital populations.

Foods with a high likelihood of transmitting listeriosis consumed by three Sydney patients diagnosed with listeriosis, by manufacturing company, 20–26 March 2013

Patient 1

Patient 2

Patient 3

Company

Creamy rice pudding

✓

Chocolate profiterole

✓

Mango cheesecake

✓

Bread and butter pudding

✓

Sandwiches (cold meats)

✓

Missing malaria? Potential obstacles to diagnosis and hypnozoite eradication

To the Editor: Bradbury and colleagues highlight some important challenges in managing Plasmodium vivax malaria when appropriate diagnostics and therapeutics are lacking.1

Their article, prompted by one of the authors acquiring P. vivax in Solomon Islands, should also prompt consideration of how these problems affect the populations of countries where our cases of imported malaria originate. The authors warn of increasing risks to Australians because of greater overseas travel. However, this is not actually happening here in Australia, where nationwide notifications have fallen dramatically in recent years2 — probably reflecting less exposure of travellers to endemic malaria as a result of significant global improvements in malaria control.3,4

Solomon Islands provides a good example of this — with Australian and international support, reductions of > 90% in malaria morbidity over the past 20 years have led to the tantalising possibility of complete elimination by 2030. However, P. vivax is problematic. In South Pacific populations, > 50% of cases arise from hypnozoite relapses, which constitute the major drivers of ongoing transmission.5 Primaquine, recommended for routine case management, is rarely used in Solomon Islands, owing to nationwide unavailability of testing for glucose-6-phophate dehydrogenase deficiency. A suitably cheap, accurate, temperature-stable point-of-care test is urgently needed, as is ongoing research to determine the best way to deploy antirelapse therapy in this setting.

Successful elimination of malaria in Solomon Islands and neighbouring countries would be a historic achievement for the health of the peoples of our region, and it would also pay a dividend for Australia’s own public health and biosecurity.