1820 Justin Kerner described food poisoning from eating blood sausage (due to
botulism). Fatal disease from eating blood sausage was recognized as early
as A.D. 900.
1849 John Snow suggested the spread of cholera through drinking water
contaminated with sewage. In 1854, Filippo Facini named the cholera bacilli
as Vibrio cholera, which was isolated in pure form by Robert Koch in 1884.
1856 William Budd suggested that water contamination with feces from infected
person spread typhoid fever and advocated the use of chlorine in water supply
to overcome the problem. In 1800, G. de Morveau and W. Cruikshank
advocated the use of chlorine to sanitize potable water.
1885 Theodor Escherich isolated Bacterium coli (later named Escherichia coli) from
the feces and suggested that some strains were associated with infant
diarrhea.
1888 A.A. Gartner isolated Bacterium (later Salmonella) enteritidis from the organs
of a diseased man as well as from the meat the man ate. In 1896, Marie von
Ermengem proved that Salmonella enteritidis caused a fatal disease in
humans who consumed contaminated sausage.
1894 J. Denys associated pyogenic Staphylococcus with death of a person who ate
meat prepared from a diseased cow.
1895 Marie von Ermengem isolated Bacillus botulinus (Clostridium botulinum) from
contaminated meat and proved that it caused botulism.