The next flu pandemic will spread rapidly due to frequent inter-city flights, writes Dr Muiris Houston, Medical Correspondent.
We live in the age of the frequent flyer virus. Of all the lessons learned from the SARS crisis in 2003, the rapid spread of the new respiratory virus throughout Asia and, in particular, the quick foothold it gained in Canada was startling.
With an influenza pandemic - a matter of when and not if - scientists have been busy modelling a number of possible scenarios. The most frightening of these involves the rapid spread of a new avian flu from south-east Asia to cities such as Sydney, Los Angeles and London, all of which have frequent and direct flights from the region. And because a flu virus spreads more rapidly than SARS, it is possible that the first we will know of the next pandemic is a sudden rise in respiratory deaths in these major cities.
Take the number of daily flights from London's four main airports to Dublin alone and it is obvious that our island status will count for nought in slowing the spread of avian flu to the Republic.
It was the acknowledgement of both the likelihood and seriousness of this scenario that led the Centre for Research in Infectious Disease in University College Dublin, in conjunction with the National Virus Reference Laboratory, to organise a recent conference, "Influenza - Preparing for the Next Pandemic".
One of the speakers at the event was Dr David Bell of the Centre for Disease Control in Atlanta, Georgia, who gave a paper on "Pandemic preparedness and issues of stockpiling and the use of antiviral agents".
He had a number of key messages: we cannot expect to have a vaccine against avian flu until four to six months after an outbreak starts; and the only practical way to reduce the number of cases and the number of deaths from an avian flu will be to administer antiviral drug therapy.
"Countries must stockpile antivirals and have a plan to deal with the next flu pandemic," he told the leading public health and infectious disease experts.
Dr Bell's comments were reinforced by Prof William Powderly, professor of medicine at University College Dublin and consultant in infectious disease at the Mater Hospital. "The only effective strategy is an anti-viral one. If there is a flu pandemic and we do not have the drugs in advance, we will not be able to get them," he said.
However, the meeting also heard that where the H5N1 strain of avian influenza is concerned, there is only one antiviral drug that works. It is oseltamivir, marketed as Tamiflu by the pharmaceutical company Roche. It has limited production capacity at a single site in Switzerland and, according to company sources, there is already a time lag between the placing of large orders and their delivery.
This is because many states have begun to stockpile the drug. Australia and Japan have bought large quantities of Oseltamivir with France reportedly ordering enough supplies to treat 25 per cent of its population. Meanwhile, here in the Republic, the Government has enough of the drug to treat just 45,000 adults (it also has a small quantity of the paediatric form of oseltamivir).
Acknowledging the complex infrastructural and ethical issues involved in influenza pandemic planning, Prof William Hall, professor of medical microbiology at UCD and chairman of the Government's influenza pandemic expert group, said: "We are looking at different scenarios and models and are actively considering all of the issues."
Among the dilemmas facing the group is how much oseltamivir to stockpile in advance of a pandemic that could be either six months or five years away. This in turn depends on whether we use the drug purely for treatment or as a prophylaxis. Do we decide to offer prophylaxis just to front-line workers? How do we define front-line workers and do they include army and Garda personnel as well as healthcare professionals? In deciding to treat the public, do we focus on older people or those at work whose wellbeing will help stabilise the economy in a time of crisis? And what of the cost to the health service in a climate where despite massive spending our A&E services are a shambles?
These issues are not just important but are potentially divisive dilemmas. There are no easy answers. It would seem to go beyond the remit of the medical profession, acting in isolation, to make ethical decisions of such depth and import.
Dr Deirdre Madden, lecturer in law at University College Cork, writing in her book, Medicine, Ethics and the Law, offers some guidance. In a section on the allocation of healthcare resources and national policy-making, she says "the problem [ of resource determination] is that of distributive justice".
But where the determination is loaded with conflicting obligations, she notes, "at the end of the day a policy should be devised that is socially and medically acceptable in the community and that takes the onerous responsibility away from individual medical practitioners".
According to Dr Darina O Flanagan, director of the health protection Surveillance Centre: "These are difficult dilemmas and these questions are as political as they are medical. What is certain is that in the face of the continued outbreak of avian influenza in south-east Asia we must act now to improve our stockpile of antivirals."
It would seem inappropriate that a small coterie of experts and Department of Health officials should make decisions that will affect our survival without the input of public discussion and debate. It is time for transparency on the many dilemmas posed by influenza pandemic planning.