WASHINGTON – Bird flu is not likely to change overnight so that it spreads from person to person, nor is it likely that a sick bird migrating to the United States will trigger human illness, the government's top bird-flu scientist said yesterday.
“One migratory bird does not a pandemic make,” Dr. Anthony Fauci, the National Institutes of Health's infectious disease chief, said in an interview with The Associated Press.
What are the odds that the H5N1 strain of bird flu will spark the next worldwide influenza epidemic? There's no way to know, Fauci said.
Reassuringly, it must undergo a series of genetic changes before it could become contagious among humans instead of just birds. Scientists might see those signs while studying the virus itself, but an early warning would be if doctors or nurses caring for someone who caught H5N1 from a bird in turn got sick, Fauci said.
“It is entirely conceivable that this virus is inherently programmed that it will never be able to go efficiently from human to human,” he said.
But the government must prepare for the worst – “it would be unconscionable not to” – as officials gear up in case bird flu does spark a human pandemic, he added.
And that makes for confusion as the public hears a drumbeat of dire warnings that has only intensified as the spring migratory season arrives.
“People ask me, 'How worried should we be?' ” Fauci said.
Not very, is his answer – unless bird flu does begin showing signs of evolving into more of a human threat.
H5N1 has infected about 190 people, and killed about half of them, mostly in developing countries. Virtually all caught it from close contact with sick chickens – mostly small children or local farmers who handled not just the birds but their droppings.
The most likely scenario: They didn't wash their hands before touching faces or preparing food, Fauci explained.
Still, if H5N1 does make the jump to easy person-to-person spread, the nation will face some tough choices: It will take four to six months to brew a vaccine, and current research suggests very high doses will be needed, meaning tight supplies. Health providers caring for the sick and vaccine factory workers will get first priority.
Typically, the most vulnerable are the first vaccinated against regular winter flu – the very old, very young and chronically ill. But scientists are debating if it might make more sense during a pandemic to instead vaccinate those most likely to spread the virus.
