Michael Osterholm, head of the University of Minnesota's Center for Infectious Disease Research and Policy, warns an avian flu pandemic in the U.S. could claim many more lives than Hurricane Katrina.
"It is not if it [avian flu] is going to happen," he said. "It is when, and where, and how bad," Osterholm said at the Woodrow Wilson International Center for Scholars in Washington.
So far, avian flu has killed about 60 humans in Asia, while being mostly restricted to birds. But experts expect the virus to change enough to spread from human to human. Osterholm said it would likely claim around 1.7 million Americans in the first year, as vaccine was slowly produced.
Canadian medical journalist Helen Branswell said she feels no one, including the World Health Organization, is ready to deal adequately with an avian flu pandemic.
"Welcome to my nightmare," she said at the conference.
The World Health Organization is prepared to begin distributing large-scale quantities of an antiviral drug to treat bird flu in humans "if and when a pandemic starts," a top WHO official said Wednesday.
Dr. Shigeru Omi, director for WHO's Western Pacific region, said the U.N. agency was ready to open its stockpile of oseltamivir, an antiviral drug, to help avert a global pandemic of the disease.
The announcement came as Indonesian Health Minister Siti Fadila Supari on Wednesday warned of a possible bird flu epidemic just hours after the death of a 5-year-old girl who was hospitalized with symptoms of the disease.
A bird flu outbreak there could quickly turn into an epidemic, the health minister warned.
Bird flu has killed at least four people in Jakarta and is suspected of sickening several others, prompting Agriculture Minister Anton Apriyantono to declare a mass cull of chickens in areas found to be "highly infected" with avian influenza.
WHO currently maintains a stockpile of about 80,000 treatment courses of oseltamivir, known commercially as Tamiflu, Omi told reporters outside a WHO conference in New Caledonia.
Asked if WHO was prepared to send tamiflu to Indonesia, Omi replied: "If and when a pandemic starts, we can send this (drug)."
The organization regards a pandemic as a multi-country outbreak of bird flu, in which the disease has been passed from human to human.
The H5N1 strain of bird flu has swept through poultry populations in large swaths of Asia since 2003, killing at least 63 people and resulting in the deaths of tens of millions of birds. Most of the human deaths have been in Thailand, Vietnam and Indonesia. Health officials in parts of Russia and Kazakhstan are also monitoring its spread.