Type A grows at up to 122 F and spores are even more heat resistant. Type A is widely distributed in soil and in animal and human intestinal tracts. Toxin forms during sporulation. Causes acute abdominal pain with some nausea, symptoms occur in 8 to 24 hours and last 12 to 18 hours. Meat and poultry products are most common routes, poor refrigeration of cooked foods speeds both bacteria and toxins.
Enterotoxigenic strain produces both heat stable and heat labile toxins.
Grows at low refrigeration temperatures. Fecal contamination human for toxigenic and invasive strains, animal reservoirs for the hemorrhagic strain. Others cause dysentery like illness. Animal slaughter believed to be source of fecal contamination of meats in Canada. Food handlers also may play role.