198 
Oxyuris vermicularis 
An interesting condition of the infected appendix was the occurrence 
at definite areas of numerous small, discrete, punctiform haemorrhages, 
which suggested the points of attachment of the nematodes. 
Probable Mode of Infection. 
This was the least satisfactory part of the whole inquiry, for in most 
cases nothing definite could be elicited from the patient regarding even 
his or her own opinion as to how worm infection took place. In two 
cases there was a certain history of worm infection, which had probably 
been continued through auto-infection. In one of these cases there was 
a family history of infection, and it is interesting to note that in this 
family three girls had appendicitis. Information as to the exact con¬ 
tents of the appendices was available only in the infected case. Still 
(1909) remarks, “ not very rarely more than one child in a family is 
suffering from threadworms ; but this does not happen with sufficient 
constancy to justify the assumption that such a source (of infection) is 
the usual or even a common one.” 
In many of the cases there was a history of chronic nail-biting, and 
this could quite easily give rise to a fresh infection or continue an 
already existing one, but as Still says : “ The number of ova on the 
fingers must be very large and easily demonstrable.” He found, how¬ 
ever, that in an experiment carried out on five children who were 
passing large numbers of threadworms that the dirt on the finger-ends 
and under the nails showed only one solitary ovum in the case of one 
child out of five. 
One infected patient had a great passion for eating raw fruit, and 
infection may have resulted from eating contaminated oranges or apples, 
etc. 
Another patient employed at a farm house was very fond of animals, 
and in her own words : “ held a lot of work with cats and dogs.” In 
this case it is possible that infection was carried by these animals from 
outside sources. 
Conclusions. 
1. That the percentage of appendices from cases of appendicitis 
infected with 0. vermicularis is a fairly high one. In Aberdeen 17 % 
were found to be infected. 
2. That normal appendices show a much lower percentage of 
infection. 
