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Wednesday 17 June 2009

RAPID ROUNDUP: Australia Swine flu alert level moves to PROTECT - Experts respond

ARCHIVE ROUNDUPS: June 12 | May 22 | Initial reaction
Also available: Science Blog | Useful links

The Federal Minister for Health and Ageing, Nicola Roxon, has announced today that Australia has developed a new response phase to manage the outbreak of H1N1 Influenza 09 (Human Swine Influenza) called PROTECT.

The new pandemic phase has been created to guide the ongoing Australian response to the disease. The new phase recognises that the infection with H1N1 Influenza 09 is not as severe as originally envisaged when the Australian Health Management Plan for Pandemic Influenza (AHMPPI) was written in 2008 and that this new disease is mild in most cases, severe in some and moderate overall. PROTECT sits alongside CONTAIN and SUSTAIN phases with a greater focus on treating and caring for people in whom the disease may be severe.

Below, flu experts respond. Feel free to use these quotes in your stories. Any further comments will be posted here. If you would like to speak to an expert, please don’t hesitate to contact us on (08) 8207 7415 or by email.

Professor Raina MacIntyre is Professor of Infectious Diseases Epidemiology and Head of the School of Public Health and Community Medicine at the University of NSW. She sits on the Scientific Influenza Advisory Group to the Chief Medical Officer of Australia and is an expert in influenza and emerging infectious diseases.

"The decision to create a new phase, protect, is to adapt to the particular circumstances of this virus, which does not appear to cause a severe illness. Partly, this could be due to the fact it is an H1 type, which is not a new H type as would be expected in a pandemic virus. In fact, the levels of pre-existing immunity to the virus in adults, particularly the elderly, reflects exposure to closely related viruses. We should not forget, however, that children aged <18 remain vulnerable, as they appear to have little immunity.

The recommendation around the use of antivirals is appropriate for this phase of the pandemic, as the disease is too widespread in the community to gain an impact through mass prophyalxis, for example. It is more important to protect front line health care workers and ensure that health services and other essential services remain functional. The same applies to the decision to reduce testing - good surveillance is still necessary to detect mutations in the virus and to measure morbidity and mortality rates, but widespread testing is not necessary."

Professor Robert Booy is Head of Clinical Research at the National Centre for Immunisation Research & Surveillance (NCIRS) based at the University of Sydney.

“’Protect’ is a proportionate response to the relatively mild disease we are seeing in most people, but there are a significant proportion of the Australian population who are at high risk of the complications of influenza and they are now the focus of surveillance and treatment. I have a very real concern that should these people contract influenza – in the first day or so of their illness it may be relatively mild, to the extent that they do not seek medical attention - my concern extends to these people not seeking early medical review when treatment can be effective. If they stay at home for three or four days and then think ‘oh no I’m getting worse,’ and seek attention from their GP, it is too late for them to be treated with the antiviral drugs that are available.

The more vulnerable people are pregnant women, people with chronic disease of the heart, liver, lung, kidney or diabetes and those with problems with their immune system. There is a real disparity between people’s symptoms in the first two days and the concern that they may become much worse further along if they have an underlying condition. So people who are healthy should take common sense approaches and use over the counter medications, stay home until they feel a bit better, but those with underlying conditions should take EARLY attention.”

Dr Dominic Dwyer is Director of the Virology Department at Westmead Hospital.

"This change in pandemic phase signals a more clinical approach to the management of influenza. We know now that 'swine flu' and ordinary seasonal influenza strains are circulating widely in Australia. Patients who have severe infection, or who are a risk of severe influenza, should be carefully assessed for antiviral treatment and laboratory testing; people with mild illness (the majority) do not generally need treatment. People with influenza should stay at home until they have recovered."

Dr Nikolai Petrovsky is Research Director of Vaxine Pty Ltd based in Adelaide.

“The doctors who look after the patients who die from influenza each year would never label it a ‘mild’ infection.

Caution needs to be exercise in interpreting what this apparent downgrade in the status of swine flu to ‘mild’ in Australia actually means. This is a pragmatic political decision, presumably as much prompted by a need to remove pressures from a public health system unable to cope with the case load of mild cases amongst the serious, as it is based on scientific evidence that this is really a ‘benign’ influenza virus. It would be a mistake to ever label influenza of any form as ‘benign’ when even in its most ‘benign’ form it causes over 1 million annual deaths globally . Don’t ever forget that influenza through its ability to mutate and exchange genetic material with related viruses has a potential to change its nature overnight from ‘benign’ to ‘highly lethal’.

It is far too early to assess the likely impact of the current relatively benign form of the swine flu given that deaths only start to be seen 2-6 weeks after initial infection, so it is too early even now to in any way assess from Australian data likely total Australian deaths before this pandemic has run its course. International case fatality rates are currently running at approximately one in four hundred, which if applied to say a conservative 2 million Australian cases through the course of the pandemic would translate to 5000 extra deaths. Nor are these deaths likely to be the same deaths as seen with seasonal influenza which are concentrated almost entirely in the elderly, whereas 50% of deaths from swine flu are occurring in much younger subjects albeit often with other underlying medical problems such as obesity, diabetes or respiratory disease. Furthermore, we have no idea of what might happen to this virus as it races through the human population as every time it reproduces and the more humans it infects the greater the probability of its mutating into a much more sinister form.

The biggest concern of all will be when this swine flu becomes established in South East Asia and particularly Indonesia and Vietnam where avian influenza remains a major concern. Should swine flu mix with H5N1 avian flu then all bets are off. If the Victorian health system cant cope with processing a few thousand nasal swab in an efficient and timely manner, then the Australian hospital and medical system had better be much better prepared if we are to have any hope of coping when a real pandemic comes to town, as it may do sooner rather than later. In the meantime, on the possibility that the swine flu isn’t benign and does pose a real threat, some of us will keep working hard to develop an effective vaccine against this now ‘mild’ influenza strain.”

Professor George Milne from the School of Computer Science and Software Engineering at University of Western Australia is also available to answer media enquiries. He is currently working at modifying a highly detailed simulation model developed for H5N1 to reflect both the biology of H1N1/2009 and the current interventions. One area of interest in this research is how the antiviral stockpile is being managed.