January 25, 1918] 



SCIENCE 



85 



sudden onset and acute gastro-intestinal 

 symptoms they present the characteristic 

 features of what is popularly supposed to 

 be ptomain poisoning:. They are in reality 

 genuine infections with pathogenic bacilli. 

 Cattle and swine are apparently par- 

 ticularly prone to infection with bacteria 

 of this group, and by far the larger number 

 of meat-poisoning epidemics are due to 

 meat from these animals. The meat of 

 sheep is rarely implicated. It is note- 

 worthy also that a large proportion of the 

 recorded meat poisoning outbreaks are due 

 to raw or imperfectlj' cooked dishes. Sau- 

 sages, especially such as are made of raw 

 meat and eaten without cooking, have been 

 incriminated in a significantly large num- 

 ber of cases. Internal oi'gans like the liver 

 and kidneys are more apt to contain bac- 

 teria than the masses of muscle commonly 

 eaten as "meat." Unfortunately, inspec- 

 tion of the meat may not give any warning 

 of the presence of pathogenic bacteria. 

 Meat in appearance quite normal to the 

 trained eye of the veterinary has been 

 kno«Ti to give rise to a meat poisoning out- 

 break. Neither is it always practicable by 

 a sj'stem of live-animal inspection to pre- 

 vent the marketing of meat from infected 

 animals. Thorough cooking is probably 

 the best means of preventing this as well 

 as all other forms of food-borne infection. 

 While paratyphoid seems to be the most 

 common form of meat^borne infection, there 

 is a possibility that other kinds of patho- 

 genic bacteria present in the bodies of dis- 

 eased food animals may sometimes be trans- 

 mitted to man in meat or meat products. 

 The possible conveyance of tuberculosis 

 in this way has been thoroughly investi- 

 gated, and it is now pretty generally agreed 

 that in most civilized countries the danger 

 of contracting tuberculosis from meat is 

 not serious. Under any ordinarily careful 

 system of inspection tubercle-infected car- 



casses are not likely to be marketed without 

 restriction, and the thorough cooking to 

 which meat is commonly subjected is a 

 further and efficient safeguard. It is ap- 

 parently true also that very large numbers 

 of tubercle bacilli are necessary to produce 

 infection of human adults through the ali- 

 mentary tract. Altogether the concurrence 

 of favorable conditions for the transmis- 

 sion of tuberculosis by meat is probably 

 rare. Bacilli of the "bovine" type are 

 seldom found in adults. Although theoret- 

 ically possible, there does not seem to be 

 any convincing evidence that eases of tu- 

 berculosis have actually resulted from the 

 use of meat. 



In several acute diseases of food animals 

 caused by bacilli pathogenic for man the 

 possibility of human cases being food-borne 

 is even more remote than in tub'.irculosis. 

 Anthrax is not at all likely to be trans- 

 mitted through food. Many diseases, such 

 as hog cholera, swine erysipelas and pleuro- 

 pneumonia of cattle that affect various do- 

 mestic animals are not known to be trans- 

 missible to man in any way. Conversely, 

 typhoid fever and Asiatic cholera are not 

 diseases from which the lower animals 

 suffer, and consequently are not infections 

 that can originate with any food animal. 



The chief infections therefore that are 

 know'u to be due to food infected at its 

 source are those — mainly meat-borne — 

 caused by the group of paratyphoid-enteri- 

 tidis bacteria and those resulting from the 

 use of infected milk. The methods for pre- 

 venting food infection are not those of 

 simple inspection of food products. It has 

 been questioned whether the amount of dis- 

 ease prevented by the ordinary methods of 

 food inspection is at all commensurate with 

 the outlay. Chapin' in considering the 



5 ' ' The Relative Values of Public Health Pro- 

 cedure," Jour. Amer. Med. Assoc, July 14, 1917, 

 69, p. 90. 



