Bird flu reaches the US

…but it’s not the deadly strain of avian influenza (high-pathogenicity avian influenza, HPAI H5N1) that has featured in endless media speculation over the last couple of years. At a time, when the Thai authorities have announced several new cases of bird flu in their country, scientists in the US have detected the low-pathogenicity (LPAI) bird flu in wild swans near the banks of Lake Erie.

Ron DeHaven, administrator of USDA’s Animal and Plant Health Inspection Service, told the Associated Press that “We do not believe this virus represents a risk to human health.” Preliminary testing showed the presence of the H5 and the N1 sub-types in the infected Michigan birds, but the USDA explains that these are more probably present because of LPAI, which is also known as American H5N1, as opposed to Asian H5N1.

Evidence of this putative low pathogenicity avian influenza (LPAI) has been found on two occasions in wild birds in the United States. In 1975 and 1986, it was detected in wild ducks. These detections occurred as part of routine sampling. LPAI H5N1 has also been detected in Canada, most recently in 2005.

Asian H5N1 has killed at least 140 people but is yet to mutate into a form that is readily transmissable between humans. Indeed, it seems the only likely way you catch this strain is through very close proximity to infected birds (i.e. sharing living quarters) or by coming into contact with feces from an infected bird.

More on the Michigan bird flu story…