A US man aged 66 has died after battling a bird flu infection for almost three weeks, the country’s apex health body, the Centers for Disease Control and Prevention (CDC), has reported. The CDC announcement read: "CDC is saddened by Louisiana's report that a person previously hospitalised with severe avian influenza A (H5N1) illness (‘H5N1 bird flu’) has passed away.

A patient death in Louisiana has become the first in the nation to be linked to the highly contagious bird flu, which has been spreading among wild birds across the country.

A 13-year-old girl in British Columbia who was hospitalized with bird flu for several weeks late last year harbored a mutated version of the virus, according to a report published this week in the New England Journal of Medicine.