1776 



HELMINTH INFECTIONS 



appear in the faeces. It is as well to remember that santonin may 

 cause blue or yellow vision. 



Oil of chenopodium may be given in gelatine capsules or in castor oil. (Fcr 

 dosage see p. 1770.) In China Quisqualis indicais at times used: 2 drachms of 

 the powder. 



Oxyuriasis. 



Definition. — Oxyuriasis is infection with Oxyuris vermicularis 

 Linnaeus, 1767 (see p. 857), and is common all over the world. 



Symptomatology. — ^The symptoms are irritation in the region of 

 the anus, with sometimes a distinct entero-colitis, and sometimes 

 slight fever. It is usually stated that there is a sense of irritation 

 in the nose. The diagnosis is to be made by finding the worms in 

 the motions after a purgative. In girls the worms may enter the 

 vagina and cause vaginitis. 



Treatment. — ^The gravid females can be killed by rectal injections 

 of quassia, alum (3i. to a pint), salt (3ii. to a pint), but the young 

 forms require internal treatment with santonin and calomel, as 

 described under Ascariasis. Flynn recommends sulphur (gr. iii.) 

 three times a day in adults,and gr. i.ss. in children, given as a cachet 

 or lozenge. A 10 to 20 per cent, calomel ointment, diluted unguen- 

 tum hydrargyri (i in 4), may be appHed to the anus, or iodoform 

 and naphthalin suppositories may be used. 



Intestinal Polyparasitism. 



Definition. — Intestinal polyparasitism is the invasion of the 

 alimentary canal by more than one species of parasite. 



Remarks. — We have, since 1903, investigated the question as to 

 which parasites are commonly present in natives of tropical Africa 

 and Ceylon, and find that it is the rule rather than the exception 

 for their intestines to harbour more than one species of parasite. 



Statistical information with regard to the prevalence of the 

 various forms in different tropical regions is still wanting, but some 

 valuable observations have been made, especially in the Philippine 

 Islands by Garrison, and in South Africa by Miss Porter. The rela- 

 tive prevalence of the various intestinal parasites in the Philippines 

 has been carefully studied by Garrison, who finds that 84 per cent, 

 of the investigated persons were infected with fifteen genera and 

 about twenty species, multiple infections being the rule, the average 

 number of infections being 2-25 per head. 



The prevalence of the various parasites were as follows : — 



Per Cent. 



Trichuris . . . . . . . . . . . . 59*0 



Ancylostoma and Necator 

 Ascaris 

 Amoebae 



Flagellates and Ciliates 

 Strongyloides 

 Oxyuris 

 Taenia 



Schistosoma japonicum . . 

 Paragonimus 

 Opisthorchis 

 Hymenolepsis 



52-0 

 26*0 

 23-0 



21'0 



3-0 

 0-8 

 0-7 

 0-6 

 0-4 

 0-3 

 o*i 



