Human case of avian flu detected in England as virus spreads among birds / Bird flu virus likely mutated within a Louisiana patient, CDC says / Bird flu outbreak leads to deaths of tigers at Vietnam zoo / Bird flu virus found in Los Angeles County wastewater / Dozens of zoo tigers die after contracting bird flu in southern Vietnam / 47 tigers dead in Vietnam zoos due to bird flu: state media / Live poultry markets may be source of bird flu virus in San Francisco wastewater / Bird flu found in western China as US combats cattle outbreak / Bird flu virus possibly found in a handful of wastewater sites, CDC says