historical_avian_influenza_outbreaks_bird_flu_spanish_flu_russian_flu_pandemics_h5n1_h1n1

pandemic history flu avian strain serotype 1878 1957 1967 vaccine outbreaks health poultry epidemiology infection h5n1 h1n1 h7n9 transmission epidemic zoonotic pathogen influenza immunization public spread mortality containment surveillance control prevention research mutation biosecurity quarantine symptoms treatment virology immunity safety emergency medical guidelines 1918 epidemiology historical h9 h3 disease