biohazard sign

aerosol anthrax attack attention banner bio biohazard biological bird bomb canine chicken coli contamination decontamination disease ebola ensign escherichia fatal flag flu h5n1 harmful hazard health hepatitis hiv human influenza level lyme measles medical microorganism mumps poison pox precaution protection salmonella sars scrapie substance swine symbol terror terrorism terrorists threat toxin vaccine varicella virus war warning waste