New bird flu mutation discovered in US as cat infections cause alarm Medical XpressGenetic Sequences of Highly Pathogenic Avian Influenza A(H5N1) Viruses Identified in a Person in Louisiana CDCBird Flu Samples From Very Ill Patient Had ‘Concerning’ Mutations The New York TimesWe ‘have our head in the sand’: Health experts warn US isn’t reacting fast enough to threat of bird flu CNNBird flu virus shows mutations in first severe human case in US, CDC says Reuters