CDC: Does the bird flu mutation make it more contagious?

Genetic sequencing of virus in the individual who died in Louisiana and the teen who was on life support in Canada show worrisome mutations, possibly after initial infection

The mutation seen in the viruses in both people is believed to help H5N1 adapt to be able to bind to cell receptors found in the upper respiratory tracts of people. Bird flu viruses normally attach to a type of cell receptor that is rare in human upper airways; it was thought that was one of the reasons why H5N1 has not easily infected people and isn’t spreading from person-to-person when it does. As one scientist explains it, “to enter a cell, the virus needs to have a key that turns the lock, and this finding means the virus may be changing to have a key that might work.” Click for more.

While bird flu has a worldwide mortality of 50%, with over a hundred identified cases in the US, most have been mild, with only one death so far. However, an otherwise-healthy Canadian teen whose exposure to the virus was not identified went from the first symptoms of bird flu (pink eye, or conjunctivitis) to being on life support in four days; she is expected to recover. The new mutation was found in both cases.