Sick poultry and infected people, rather than migratory birds, are more likely to bring the H5N1 bird flu virus into the United States, although that was unlikely to happen soon, a leading virologist said.
HONG KONG Sick poultry and infected people, rather than migratory birds, are more likely to bring the H5N1 bird flu virus into the United States, although that was unlikely to happen soon, a leading virologist said.
Robert Webster from St. Jude Children's Research Hospital in the United States said the virus was more likely to be introduced via human activities, such as poultry smuggling.
"There is no H5N1 in the United States. And I don't think it is going to get there this year by wild birds ... maybe not even next year," he said on the sidelines of a conference organised by Fort Dodge Animal Health, a unit of Wyeth.
"I think it is more likely that it could be smuggled in some poultry or ... an infected person could bring it in to the United States," the influenza expert said late on Monday.
Since re-emerging in parts of Asia in late 2003, the virus has killed at least 123 people.
It spread especially quickly in birds this year, moving into parts of Africa, the Middle East and Europe. In the past five months alone, more than 30 countries have reported outbreaks in poultry or wild birds.
"It is very easy to blame the wild bird. But I think the spread of the virus is a combination of human spread and wild bird spread," said Webster.
"The main spreaders of highly pathogenic avian influenza in the past were humans," he said, detailing human activities, including movement of food trucks across borders or even veterinarians.
His views were supported in part by an official from the World Animal Health Organisation (OIE).
TRADE A CRITICAL FACTOR
Bonaventure Mtei, the OIE's representative for southern Africa, said there have been few signs of migratory birds carrying the virus in the continent.
"So we think trade is the most critical factor in the interaction of the disease in Africa," he told Reuters during the OIE general assembly in Paris on Monday.
The findings contrast sharply with the situation earlier this year in Europe, where wild birds migrating from near the Black Sea carried H5N1 as far as France. Infected birds, mostly swans, flew westwards. Hundreds of cases turned up in Europe and some farms were infected.
The migration versus trade theories have been the subject of much speculation. Conservationists have always said that some disease "hotspots" do not correspond to known migratory routes.
The U.S. government, believing the arrival of H5N1 is inevitable on the wings of water birds, has ordered increased testing of migratory fowl in Alaska and elsewhere.
California officials expect bird flu to arrive on the U.S. West Coast this summer in what could be the first sign in the United States of the virus.
Officials have said H5N1 was likely to be carried into either the U.S. east or west coast by migrating birds starting their journeys south, either from Alaska on the Pacific Flyway, or the Atlantic Flyway on the other side of North American continent.
(Additional reporting by David Evans in Paris)