US Unlikely to Have Enough Vaccines to Stop Avian Flu
The 19 medical experts who attended the Pandefense 1.0 meeting in November gave a median estimate of a less than 1 percent chance that the U.S. will have adequate stockpiles of vaccines or antiviral drugs to prevent a pandemic within the next three years. The same experts gave a median estimate of 15 percent for the probability that the avian flu virus will mutate into a strain that can spread efficiently by human-to-human contact within that time. Their median worst-case estimate of the number of people who would die, should that happen, was 6 million in the United States and 180 million worldwide. Their median best-case estimates were 500,000 dead in the United States and 20 million worldwide. (Source : Bird Flu News )
"It surprised me that they thought it was going to be this bad," said Wandi Bruine De Bruin, lead author of the study and research faculty member in the Department of Social and Decision Sciences at Carnegie Mellon.
The survey also included 17 non-medical experts from a variety of fields who were more pessimistic about the likelihood of human-to-human transmission, giving a median 60 percent chance that it would occur within three years. They did, however, have more faith in medical science, giving a median 15 percent chance of the United States having enough vaccine and a 30 percent chance that the nation would have enough antiviral medications to halt a pandemic.
"The medical experts' estimates suggest this is a bigger risk than anything else we are facing," said Baruch Fischhoff, a study co-author and the Howard Heinz University Professor of Social and Decision Sciences and Engineering and Public Policy at Carnegie Mellon.
Both the medical and the non-medical experts agreed that the greatest hope for mitigating the effects of an avian flu outbreak among humans lies in heightened global surveillance and, should the virus become pandemic, hand washing, mask wearing and social distancing. Unfortunately, the efficacy of such strategies in preventing the spread of infectious diseases has not been extensively studied, Bruine de Bruin said. Although the federal government has expressed a commitment to open communication about these risks, its messages have not yet been scientifically evaluated, according to Fischhoff.
Bird flu has hit 55 countries, killed more than 500 people and seems to be spreading quickly, the U.N. official in charge of tracking the virus said Wednesday.
Dr. David Nabarro said the virus has led to the deaths of some 200 million birds and has impoverished millions of small poultry farmers.
Between 2003 and 2005 the virus was reported in 15 countries. But in the first four months of this year it has moved rapidly to 30 new countries, with major outbreaks in Turkey, Iraq, Israel, Gaza, Egypt, Afghanistan, Pakistan, Myanmar, India, Nigeria, Niger, Cameroon and Bukina Faso.
"I suspect we're going to see further spread of H5N1 into other countries," he said, referring to the deadly and virulent strain of the virus.
"This is very similar to the virus that caused the influenza pandemic of 1918," Nabarro said. It's not identical but it's similar. ... So therefore, the 1918 virus, which caused this huge pandemic associated with 40 million deaths, seems to have a successor waiting in the wings."
Nabarro, the U.N.'s chief coordinator for avian influenza, spoke at a meeting organized by the United Nations Foundation on how to inform people around the world of the bird flu threat.
He said the H5N1 virus is known to have stricken more than 200 people, but it probably has affected "many, many more."
Tom Cruse writes articles for Only Health