STUDY OF INTESTINAL PARASITES. 



83 



Table V shows the relative frequency of the various parasites found 

 at the two haciendas. The variations practically are negligible, excepting 

 in the case of Trichuris which was found nearly twice as frequently at San 

 Antonio as at Maluno; this is accounted for by the presence at the 

 •former place of the Visayans and the proximity of certain cabecerias 

 to Ilagan Central. No infections with Hymenohpis or Strongyloides 

 were found at Mahmo. 



Table V. — Relative frequency of the various parasites found at San Antonio and 



Maluno. 



Place. 



Nun) 



- 



Infected. 



Ascaris. 



Hookworm. 



Trichuris. 



exam- 

 ined. 



Num- 

 ber. 



Per 

 cent. 



Num- 

 ber. 



Per 

 cent. 



Num- 

 ber. 



Per 

 cent. 



Num- 

 ber. 



Per 

 cent. 





3,310 

 968 



2,819 

 837 



85.17 

 86.49 



2,082 

 571 



62. 90 

 58.99 



1,788 

 538 



54.02 

 55.58 



296 

 46 



8.94 

 4.75 



Maluno 





Place. 



Oxyuris. 



Tmnia. 



Hymenolepis. 



Strongy- 

 loides. 



Total infections. 



Num- 

 ber. 



Per 

 cent. 



Num- 

 ber. 



Per 

 cent. 



Num- 

 ber. 



Per 

 cent. 



Num- 

 ber. 



Per 



cent. 



Num- 

 ber. 



Per cent. 



San Antonio 



51 

 13 



1.54 

 1-.S4 



45 

 14 



1.36 

 1. 4.'> 



5 

 



0.15 

 0.00 



4 

 



0.12 

 no 



• 4, 272 

 1,182 



129. 06 

 122-11 



Maluno 



























1 



" One trematode infection included. 



Because the findings at the two places differ so slightly, they will 

 be considered together in the following pages, excepting under the 

 subject of geogi-aphic distribution, when conditions at San Antonio 

 alone will be dealt with. 



SEVERITY OF INFECTIONS. 



The severity of the infections is measured by an impression of the 

 number of ova seen in the specimens. Many of those with Ascaris, es- 

 pecially the ones occurring in children, were heavy, and those with 

 Trichuris, Oxyuris, Hymenolepis and Strongyloides were light except- 

 ing a few cases of Trichuris. In one case the ova of the hookworm were 

 very numerous, in a few instances not exceeding 15 ova per cover slip 

 preparation were seen, while in the vast majority of cases, from 1 to 

 3 ova were present. 



It is surprising to find practically only mild infections with the hook- 

 worm in a district where the parasite is found in over 50 per cent of the 

 population. It has occurred to me that the flooding of the lowlands 

 during the rainy seasons may be considered in this connection. Exper- 

 iments have shown that fresh eggs of the hookworm die if they are placed 

 in water, or if the culture medium (sand, or animal charcoal) is kept 



