In a new development, it has been found that the first severe case of bird flu in the US involves mutations not seen in samples from an infected backyard flock on the patient's property, informed US Centers for Disease Control and Prevention. The analysis of the patient's sample from Louisiana - aged 65 and suffering from severe respiratory illness - showed mutations in the hemagglutinin (HA) gene, the part of the virus that plays an important role in it attaching to host cells, said CDC. One of the mutations was also noticed in a bird flu virus sample taken from a teenager in British Columbia who was in critical condition in a Vancouver hospital.
However, the health agency has affirmed that the risk to the general public remains low.
