2.6 Escherichia coli
There are hundreds of strains of Escherichia coli (Gram-negative bacterium). Despite most of the strains
are harmless, E. coli O157:H7 produces a powerful toxin that can cause severe illness. The physiological
effects of E. coli O157:H7 range from diarrhoea to serious and life-threatening conditions [22]. E. coli
O157:H7 has been found in the intestines of healthy cattle, deer, goats, and sheep. E. coli O157:H7 is a
leading cause of foodborne illness [23].