1880.] PUHLIC D0CUMP:NT — No. 34. 123 



can be considered only as rough a[)proximations to an index 

 of the degree of infection, but on the average it was about 

 one grain of fiesh from each hog. A synopsis of the cases 

 is as follows : — 



With 1 parasite 87 cases -^ 1 = 87.* 

 " 2-5 " 171 " ~ 4 = 43. 



436 



In 45 cases one or more of the parasites were dead. 



What degree of infection is implied by finding only one 

 trichina in six slips from a single hog? To find only one 

 specimen of the parasite would seem, at first sight, to mean 

 a degree of infection which is of little or no significance, 

 either to the animal infected or to the consumer. But, how- 

 ever unimportant the infection may have been in the life of 

 the hog thus feebly affected, even such cases are capable of 

 producing serious results in the consumer. As has been 

 said, the amount of meat examined from any one hog is ex- 

 cessively small — only about one grain. Since in a pound of 

 meat there are 7,000 grains, it follows that, if one were to 

 eat half a pound of such meat uncooked he Avould import into 

 his person no less than 3,500 living worms, over half of 

 which it has been proved would be productive females, each 

 one of which would bring forth at a minimum about 1 ,500 

 minute worms, or, at a very low estimate, an aggregate of 

 say two and one-half million worms. But, assuming that 

 the average infection of the body falls considerably below 

 that of the pillars of the diaphragm, — assume it to be one- 

 fifth the latter, t — still the number of migrating young 

 trichinae (half a million) would doubtless be enough to have 

 a real effect on the health of the patient. 



* The figures of the last column are averages for the lots, obtained by dividing 

 the numV)er of cases by the number of grades embraced In the corresponding lot; 

 thus, '• 2-5 parasites " embraces four grades — the 2- 3- I- and 5- parasite gn»dos. 



t A little farther on there are presented some facts and estimates on the degree of 

 infection. 



