4SO 



THE BACTERIA OF FOOD POISONING 



3, MISCELLANEOUS BACTERIA 



Bacteria of diverse nature have been accused on more or less cogent evidence of 

 causing outbreaks of "food poisoning" either by tissue invasion or by their toxic 

 products. 



a) B. proteus. — ^There is no doubt that some members of the large and variable 

 Proteus group are definitely pathogenic/ Whether Proteus bacilli are ever definitely 

 concerned in outbreaks of food poisoning is not so certain. The mere presence of 

 these organisms is not especially significant as they are found generally in decompos- 

 ing animal matter and are probably not infrequently swallowed with food. Proteus 

 is common in sewage and has been reported by several observers as present in the 

 human intestinal tract, especially in disordered conditions. A number of outbreaks 

 of food poisoning have been attributed by various observers to this organism, but 

 Savage,^ after a detailed discussion of nine reported instances, concludes: "From this 

 summary of outbreaks it is evident that for none of them was it established that B. 

 proteus was etiologically concerned." 



h) Staphylococcus. — One of the most definite instances of food poisoning due to 

 microbic products is that reported by Barber,-' who showed that acute attacks of 

 gastro-enteritis were produced by milk in which a toxic substance had been elaborated 

 by a white staphylococcus. The staphylococcus occurred in almost pure culture in 

 the udder of a cow that stood in direct epidemiological relation to the outbreak. 

 The cause of this outbreak was further demonstrated by the reproduction of typical 

 symptoms in a human volunteer who drank milk that had been inoculated with the 

 suspected staphylococcus. 



c) Streptococcus. — Linden, Turner, and Thom^ have reported two outbreaks at 

 widely separated points in the United States (Biddeford, Maine, and Kansas City, 

 Kansas) which they attributed to a streptococcus found in certain lots of cheese, one 

 an imported Albanian cheese, the other an American Cheddar manufactured in 

 Wisconsin. Savage makes the following comment: 



The outbreaks are most interesting, but the proof that they were due to the streptococcus 

 isolated is obviously very incomplete. Apparently this living streptococcus was prevalent 

 in other samples of the fresh cheese, but only one small outbreak resulted. The distribution 

 of this streptococcus in cheese which did not cause illness does not appear to have been 

 investigated. It is unfortunate that essential epidemiological details are omitted.s 



It seems probable that bacteria of various kinds as yet unidentified may by 

 infection or through a preformed poison cause occasional cases or epidemics of food 

 poisoning. Numerous instances are on record where some particular article of food 

 has appeared definitely at fault, yet in which no recognized food poisoning micro- 

 organism could be discovered. A number of outbreaks of mdeterminate cause are 

 included in the remarkable series of reports in the United States Naval Medical 



• Larson,, W. P. and Bell, E. T.: J . Exper. Med., 21, 629. 1915; Warren, S., and Lamb, M. E.: 

 J. Med. Research, 44, 375. 1923-24. 



= Savage, W. G.: Food Poisoning and Food Infections, pp. 126-30. Cambridge, 1926. 

 ^Barber, ]\L A.: Philippine J . Sc, 9, 515. 1914. 



■" Linden, B. A., 'l\irner, \V. R., and Thom, C: Pub. Health Rep., 41, 1647. 1926. 

 5 Savage, W. G.: Bull, llyg., 2, 97. 1927. 



