476 
The Philippine Journal of Science 
1921 
There is some diversity of opinion regarding the patho- 
genicity of Isospora hominis. Fantham,(7) in a paper which 
I regret is not accessible to me, has claimed success in infect- 
ing kittens with Isospora hominis, and to have produced a 
condition in the intestines “resembling that seen in the 
human intestine examined post mortem.” In a footnote (p. 186) 
Dobell(3) comments: “This, however, has never been de- 
scribed, so far as I am aware; and the statement can hardly 
be accepted without some concrete evidence to support it.” 
Animal experiments, with this exception, that have so far 
been attempted with this parasite have uniformly failed, 
attempts having been made with kittens, a mouse, and two 
young puppies. Noc(l2) also fed the cysts to a white rat, but 
up to the time he wrote his paper he had secured no evidence 
that infection had taken place. 
Practically all writers agree that the parasite has a certain 
potentiality for harm, but one great objection to many of the 
observations made lies in the fact that the patients were suffering 
from dysentery or some other intestinal ailment that would 
tend to obscure any existing coccidial symptoms. In one case 
studied by Wenyon(l7) in which there were a concomitant 
infection with Entamoeba coli and dysenteric symptoms, no 
cause for the dysentery could be found and Wenyon remarks 
that “It may have been that the dysenteric symptoms of this 
case were due to the coccidium, for no pathogenic bacteria 
had been isolated from the faeces;” which, however, does not 
necessarily follow, as one may gather from the conservatism 
of the statement. Dobell (2) states his conclusions (p. 68) as 
follows : 
No evidence is brought forward to show that either of the Coccidia 
found ( Isospora or Eimeria) is pathogenic. As both of these are tissue- 
parasites, which probably invade the cells of the small intestine, it is 
possible that they may give rise to pathological conditions. At present 
there is no indication that this is so. It may be added that many animals 
appear to suffer no inconvenience from immense infection with coccidia; 
and it is quite possible therefore that the forms occurring in man are of 
no practical importance. 
The watery diarrhoea reported in three of Gragg’s Mesopo- 
tamia-Bombay cases looks interesting, but the cases are too 
clouded by dysenteric complications to admit of much stress 
being laid upon them. It is greatly to be regretted that the 
opportunity afforded for a study of the intracellular stages of 
