At least 29 nations have reported initial cases of avian influenza during the past seven weeks, reflecting the ineffectiveness of bird culling.
The viral disease has been newly reported in Nigeria, Israel, India, Sweden and elsewhere, with scientists in the United States estimating bird flu is likely to arrive in North America this year.
"We expected it to move, but not any of us thought it would move quite like this," said Dr. David Nabarro, the U.N. coordinator on bird flu efforts, told The Los Angeles Times.
Researchers initially thought culling millions of chickens, ducks and other birds would contain or even eradicate the virus. It has not.
The virus has so far infected 186 humans, causing 105 deaths, according to the World Health Organization. The fear is the virus will mutate, becoming easily spread between humans and creating a pandemic that potentially could kill millions of people.
"Each morning I sit down at the computer ... there's another country, another outbreak or another human case," Nancy Cox, chief of the influenza branch at the U.S. Centers for Disease Control and Prevention, told the Los Angeles Times. "It keeps us breathless," she said.
Copyright 2006 by United Press International
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