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SCIENCE 



[h. S. Vol. XXXIX. No. 995 



temperature of about 0° F. were dead, and 

 many of the remaining 141 showed only faint 

 signs of life. 



Eesults similar to the above were obtained 

 from tests of trichinosed meat on guinea-pigs. 

 Guinea-pigs fed with infested meat after its 

 exposure to a temperature of about 0° F. for 

 two, three, six and seven days, respectively, 

 showed no trichinse when killed and examined 

 three weeks after feeding. A guinea-pig fed 

 with meat from the same source which had 

 been kept at a temperature of 11° to 15° F. 

 for six days showed trichinae when killed and 

 examined three weeks after feeding. 



It is evident that the results of these experi- 

 ments, if confirmed by further investigation, 

 are likely to be of great practical importance. 

 Trichinosis in man is a very painful, fre- 

 quently fatal, disease, and moreover it is com- 

 paratively common. Roughly estimated there 

 have been recorded in the medical literature 

 of this country about 1,200 cases of trichinosis, 

 of which about 200 resulted in death. These 

 figures undoubtedly include only a fraction of 

 the cases which actually occur. Many cases 

 of trichinosis recognized as such are not re- 

 ported, and there is good reason to believe that 

 the vast majority of cases are unrecognized, 

 commonly passing as rheumatism, atypical 

 typhoid fever, or as some other disease of un- 

 certain nature. Some years ago Williams at 

 Buffalo reported that he had found the para- 

 site in 27 out of 505 cadavers examined for its 

 presence, death in no instance having resulted 

 from trichinosis. If Williams's findings be 

 assumed to be statistically adequate, it may be 

 concluded that five persons out of every 100 

 among the population typified by the 505 

 cadavers examined by him suffered from tri- 

 chinosis at some time in their lives and recov- 

 ered, in addition to which an indefinite number 

 died of the disease. An extensive examina- 

 tion of cadavers throughout the United States 

 would be required before general conclusions 

 as to the prevalence of the parasite could be 

 reached, but the numerous reported cases and 

 Williams's figures are sufScient to prove that 

 Trichinella spiralis is of common occurrence 

 in man in this country. The prevalence of the 



parasite in man of course depends upon its 

 prevalence in hogs and the extent to which un- 

 cooked pork is used as food. The microscopic- 

 inspection of over 8,000,000 hogs in this coun- 

 try during a period of nine years showed that 

 1.41 per cent, were infested with living 

 trichinae, in addition to which there were 1.16 

 per cent, containing trichina-like bodies or dis- 

 integrating trichinse, or a total of 2.57 per 

 cent. The custom of eating raw pork is not 

 unusual among the population of the United 

 States as evidenced by the large quantities of 

 various pork products intended to be eaten raw 

 that are prepared by meat-packing establish- 

 ments. Incidentally it may be noted that the 

 consumption of such products seems to be in- 

 creasing from year to year. In view of the 

 frequent occurrence of trichinae in hogs and 

 the not altogether rare practise of eating raw 

 pork it is not surprising that trichinosis should 

 be a rather common disease in the United 

 States. Inasmuch as warnings against the 

 eating of raw pork seem to have little effect in 

 discouraging this dangerous custom, certain 

 countries in Europe have tried at great expense 

 and not altogether successfully to guard the 

 consumer by means of a system of microscopic 

 inspection. 



In this country microscopic inspection of 

 all the hogs slaughtered under Federal super- 

 vision would require an expenditure of prob- 

 ably not less than $5,000,000 per year over and 

 above the sum already expended for federal 

 meat inspection. Apart from other difficulties 

 and objections of various sorts, the matter of 

 expense alone is a serious diificulty in the way 

 of a general trichina inspection, and as yet 

 the federal government has not attempted 

 guch an inspection. In recent years, however, 

 there has been some consideration of the ques- 

 tion of a partial trichina inspection; that is, 

 a microscopic inspection of those hogs slaugh- 

 tered under federal supervision which are in- 

 tended to be used in the manufacture of pork 

 products of kinds customarily eaten raw. 

 Such an inspection though it would by no 

 means remove the danger, because even the 

 best inspection is essentially imperfect, would 

 greatly reduce the risk involved in the eating 



