Docs fear world not ready for bird flu pandemic

The specter of a bird flu pandemic haunts epidemiologists who said US and world preparedness falls short, should the H5N1 virus become transmissible between humans.

"I hope H5N1 won't be able to acquire transmissibility because this is an extraordinary quagmire," Robert Webster, a world-class expert on the virus, said at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy meeting this week in San Francisco.

"Don't become complacent. We need to put into place every possible way" to stop this virus from transmitting from human to human, he said.

"If it does happen, we have to be prepared for a pandemic.

"It would be a pandemic flu, it's an absolute certainty," said the epidemiologist from St Jude Children's Research Hospital in Memphis, Tennessee.

He said that the extremely pathogenic H5N1 virus causes symptoms in humans similar to those of the H1N1 pandemic of 1918, including diarrhea, which is not a good sign.

"In 1918 at least a half million American died. With the current population structure in the US and nothing else different, two million would die," said Arnold Monto, epidemiologist of the University of Michigan.

"We have learned a lot from seasonal influenza which is applicable to pandemic influenza. The basic thing that will happen is that we have to look very quickly once the pandemic has started to find out what the characteristics are like -- like in 1918 where young adults were dying or if it's like 1957 (and) 1968, which had more the characteristics of a very severe seasonal influenza."

In 1918, the H1N1 or "Spanish" flu killed 20 million to 50 million persons worldwide, because it had mutated into a form that could be transmitted from one human to another.

"Like the Spanish flu, if (the bird flu is) going to acquire transmissibility, it has been estimated it will take something like 10 critical mutations," Webster said.

"So with its huge distribution in the world," Webster said, the virus could become transmissible "anytime."

Worse yet, Webster said, "We know surprisingly little of what constitutes the ability of the virus to transmit" human to human.

That said, "It makes sense to stockpile vaccines even though it doesn't prevent infection, there is a lot of difference between infection and death," he said.

"There is an urgent need to increase the influenza vaccine manufacturing capacities in the world because the capacities are too low."

David Bell of the US Centers for Disease Control and Prevention did not look to stopping the epidemic completely.

"The goal of these measures isn't to stop a pandemic but rather to mitigate its impact on the community, to flatten the epidemic, to take the pressure out of the health care system by reducing the number of people getting sick," he said. (


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