From the FEB/MAR 2006 issue of Seed:

avflusimon.jpg A researcher (not Dr. Kennedy Shortridge) takes a look under the microscope. Credit: Andrei Tchernov

The World Health Organization says it's a matter of when, not if. Economists say its spread will be "relentless," the suffering caused "incalculable," and that it may have an $800 billion impact.

While praising the WHO and UN for galvanizing a complacent world into preparedness (as of November, an estimated 120 countries had preparedness plans, up from just 50 last August), one of the world's leading influenza scientists worries the international response to avian flu may be missing the point--how and why pandemics start.

"I have no idea if H5N1 will cause a pandemic," says Dr. Kennedy Shortridge, an emeritus professor of microbiology at Hong Kong University who has spent three decades studying influenza viruses. "We can't be certain at all." Kennedy is uniquely qualified to comment: he designed and led the benchmark campaign against H5N1, eradicating it from Hong Kong in 1997 after it killed six people. (The effort won him the highly prestigious Prince Mahidol Award in Public Health.)

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Shortridge believes H5N1 is presently in a "smoldering phase" of evolution similar to that undergone by the 1918 virus before it eventually broke out. He thinks the process could last another decade while the virus tests human defenses.

Pandemic viruses, says Shortridge, "have hierarchical capabilities. That is: the ability to enter the human host, escape the immune system and move on to produce new variants of itself." He suspects H5N1 may not possess this intrinsic ability, a prognosis that was echoed by Dr. Peter Palese, head of Mount Sinai School of Medicine's Microbiology faculty, who told The New York Times, "The virus has been around for more than a dozen years, but it hasn't jumped into the human population. I don't think it has the capability."

The global preparedness effort, beyond developing new super-drugs or vaccines as vital last lines of defense, says Shortridge, should be highlighting the need to prevent these outbreaks from occurring at all. He insists the way to truly beat viruses like H5N1 is to eradicate the conditions that foster a virus' rise from benign to lethal. In the current instance, that means acting while the virus is still "smoldering"; an opportunity humanity did not have in 1918.

"The industrialization of poultry is the nub of this problem," says Shortridge. "We have unnaturally brought to our doorstep pandemic-capable viruses. We have given them the opportunity to infect and destroy huge numbers of birds and...jump into the human race."

An avian flu outbreak is potentially only as big as the flock it infects, reasons Shortridge. The larger the flock, the greater the surface area of risk for further onward transmission. Modern poultry-raising operations, in which tens of thousands of birds may be contained in a single shed, provide the greatest risk scenario in history.

A second, but equally important, element is cooperation. Shortridge said, "Pandemic influenza can be beaten simply if we can act together--in terms of the way we treat animals, how we cooperate for the common good, how we share information. Pulling all these strands together will lead to a better human condition all round."

In a hyper-connected world, where most live just one commercial airliner away from the next potential super-bug, Shortridge sees the emergence of viruses like H5N1 as evidence of a deeper sickness, one that leads us to run roughshod over nature, ignoring the balance that has governed the planet for millennia.

"The deeper question is why, at this point in history on earth, are we having so many zoonotic diseases?" asks Shortridge. "Something is not right. Human population has exploded, we are impinging on the realms of the animals more and more, taking their habitats for ourselves, forcing animals into ever more artificial environments and existences."

, written by Simon Cooper, posted on March 6, 2006 12:36 AM, is in the category Health. View blog reactions