Deadly strain divides. U.S. researchers announced Monday that the much-feared H5N1 strain of avian influenza has in fact split into two strains. [News Source]

Bird flu mutation ‘adds to threat of human pandemic.’ The virus that causes bird flu has split into two distinct genetic subgroups, widening the gene pool from which a form that could trigger a human pandemic might evolve. [News Source]

Bird flu expected as soon as this year. Three Bush administration Cabinet secretaries — saying they wanted to inspire preparation, not alarm — told reporters Monday that the dangerous strain of avian flu could come to this country in wild birds. [News Source]

Bird flu could hit Britain, but might not hurt. Bird flu might arrive in Britain in wild birds in August or September, but poultry could escape the virus that has wiped out a farm in France. [News Source]

U.S. farmers prepare for arrival of Asian bird flu. The U.S. government announces that it is expanding efforts to test wild and domestic birds for the deadly Asian bird-flu virus. [News Source]

Bird flu could shave $60B off GDP, manufacturers say. Most Canadian businesses aren't yet prepared for a bird flu pandemic that could eventually cost the economy $60 billion. [News Source]

U.S. expands bird flu screening. Detection of the highly pathogenic avian flu virus H5N1 inside the United States could come as early as this year, as government officials unveiled plans to increase monitoring and expand screening of migratory birds that could bring it. [News Source]

Scientists hand Ottawa a blueprint for a mass cull of bison. The document reads like a doomsday scenario for Canada's largest free roaming herd of bison. [News Source]

Malaysia to discuss poultry import ban with Singapore. The Ministry of Agriculture and Agro-Based Industry will discuss the ban on imports of poultry and poultry products from Perak with Singapore following the detection of bird flu in the state. [News Source]

Business prepares for the possibility of avian flu in the US. The deadly strain of avian flu has not been found anywhere in the Western Hemisphere, but Mark Holden, a chicken grower for Tyson Foods in Ellijay, Ga., is not taking any chances. [News Source]

Two bird flu strains snarl vaccine search. The H5N1 bird flu in humans has evolved into two separate strains, a development that will complicate the search for a vaccine and the prevention of a pandemic. [News Source]

Ag secretary offers reassuring words about spread of avian influenza. The millions of migratory birds heading to North America this spring pose a significant health threat to poultry, but not people, U.S. Department of Agriculture secretary Mike Johanns said Monday. [News Source]