STUDY OF INTESTINAL PARASITES. 



85 



years of age, there was a decided fall in the frequency of this parasite 

 as age advanced, excepting a slight rise in females over 50 years old. 

 Trichuris showed but slight variations as to sex and age. It was found 

 more frequently in persons over, than in those under 15 years old. 

 Infections with Taenia were met with more frequently in males over 50 

 years old, all of those with Hymenolepis occurred in persons under 16 

 years of age and Oxyuris was found oftener in individuals under 15. The 

 hookworm occurred more frequently in males than females in corre- 

 sponding age groups, excepting the small group of infants less than one 



year old. 



Table VII. — Age distribution of infections. 



Age (years). 



Num 



. 



Infected. 



AscarU. 



Hookworm. 



Trichuris. 



exam- 

 ined. 



Num- 

 ber. 



Per 



cent. 



Num- 

 ber. 



Per 



cent. 



Num- 

 ber. 



Per 

 cent. 



Num- 

 ber. 



Per 

 cent. 



Under 1 



1 __ ._ 



20 



74 



184 



162 



153 



172 



161 



375 



495 



1,100 



955 



427 



1,796 



2,482 



3 



37 

 138 

 146 

 126 

 155 

 141 

 337 

 443 

 980 

 789 

 361 

 1, .526 

 2,130 



15.00 

 50.00 

 75. 00 

 90.12 

 82.35 

 90.12 

 87.58 

 89.87 

 89.49 

 89.09 

 82.62 

 84.54 

 84.97 

 85. 82 



3 



36 

 132 

 135 

 116 

 141 

 126 

 270 

 346 

 671 

 472 

 205 

 1,305 

 1,348 



15.00 

 48.65 

 71.74 

 83.33 

 75.82 

 81.98 

 78.26 

 72.00 

 69.90 

 61.00 

 49.42 

 48.01 

 72.66 

 54.32 



1 

 7 



25 



31 



38 



47 



58 



202 



308 



741 



591 



277 



717 



1,609 



5.00 

 9.46 

 13.59 

 19.14 

 24.84 

 27.33 

 36.02 

 53.87 

 62.22 

 67.36 

 61.89 

 64.87 

 39.92 

 64.83 











6 



6 



6 



11 



14 



33 



38 



104 



7? 



48 



114 



228 







3.26 

 3.70 

 3.92 

 6.40 

 8.70 

 8.80 

 7.68 

 9.45 

 7.96 

 11.24 

 6.35 

 9.19 



2 



3 



4 . 



5.- _ . 



6 



7 to 9 



10 to 14 



15 to 30 . 



31 to .50 



Over 50 



Under 15 



15 and over : 





Age (years). 



Oxyuris. 



Txnia. 



Hyme 



nolepis. 



Strongy- 

 loides. 



Total infections. 



Num- 

 ber. 



Per 

 cent. 



Nu 

 be 



m- 



r. 



Per 

 cent. 



Num- 

 ber. 



Per 

 cent. 



Num- 

 ber. 



Per 

 cent. 



Num- 

 ber. 



Per 

 cent. 



Under 1 







1 



3 



1 



4 



6 



4 



7 



6 



13 



13 



6 



32 



32 









 

 

 



1 

 



1 





 2 

 18 

 23 

 14 

 4 

 55 







 

 

 

 1 

 

 

 2 

 

 2 

 

 

 3 

 2 



0.65 



0.53 

 0.18 



0.17 

 0.08 





 

 1 

 

 

 

 



1 







1 



1 







2 

 2 





4 



44 



167 



174 



165 



205 



203 



515 



700 



1, 550 



1,176 



550 



2,l77 



3,276 



20.00 

 59.46 

 90.76 

 107. 41 

 107. 84 

 113.37 

 126. 09 

 137. 33 

 141.41 

 140. 91 

 123. 14 

 128. 81 

 121.21 

 1,32. 40 



1 - . 



1.35 

 1.63 

 0.62 

 2.61 

 3.49 

 2.48 

 1.87 

 1.21 

 1.18 

 1.36 

 1.41 

 1.84 

 1.29 







2 





0.54 



3 





4 



0.65 





5 





6 



0.62 





7 to 9 - 



0.27 



10 to 14 . . 



0.40 

 1.64 

 2.41 

 3.28 

 0.22 

 2.22 



15 to 30 



0.09 

 0.10 



31 to 50 



Over 50 



Under 15 



15 and over 



0.11 

 0.08 























i 



