Bird flu or avian influenza refers to influenza caused by viruses adapted to birds. The United States health authorities have reported that bird flu is spreading among wild birds, chickens and turkeys across the country. The US Department of Agriculture reported, "Since December 2014, cases of the highly pathogenic H5 avian influenza virus have spread through 16 states in the midwestern and western parts of the country, as well as some parts of Canada, infecting nearly seven million birds." The outbreak poses a low risk for people being infected with the virus.
Alicia Fry, branch medical officer at the US Centers for Disease Control and Prevention said, "The H5 virus in North America looks different than the H5N1 bird flu circulating in Asia, where it has jumped from birds to people. The CDC considers the risk to the general US public to be low at this time. That said, human infections with similar avian influenza viruses have occurred and it is possible that we may see human infections with the viruses associated with recent US bird flu outbreaks. While we are cautiously optimistic that there will not be human cases, we must be prepared for that possibility."
Most cases of human infection with avian flu have occurred when people had prolonged and close contact with infected birds. Health authorities are continuing to study the virus and are working on a potential vaccine that could be administered to people. However, the arrival of warmer weather in spring and summer could limit the spread of the virus. John Clifford, the chief veterinary officer of the US Department of Agriculture, said, "We know that this virus doesn't like heat so when it gets up to a certain level of temperature this virus doesn't survive, usually."