Botulism is a rare paralytic disease caused by botulinum neurotoxin (BT), a protein produced by the soil bacteria Clostridium botulinum. Different strains of the bacteria make different types of toxin. However, only four of the seven known BT types (A, B, E, and F) cause human botulism. One of the most deadly known toxins, estimates indicate that approximately 70 one millionths of a gram can kill an average adult. However, of the approximate 140 cases per year in the U.S., there are usually only 1-3 deaths.