Strongyloides infections in man and animals in the isthmian canal zone

Abstract

From a study of strongyloides infections in man and animals in this region, it has been determined, in confirmation of the view of Grassi, Calmette, .and others, that they are not causative factors in the production of diarrhea. The mother worm, however, burrows into the mucosa and deposits her ova there. Certain tissue reactions take place and are evidenced by the cellular proliferation in those portions of the intestines occupied by the nematodes. In animals, there is an associated anemia, not positively attributable to the strongyloides, but, on the other hand, not attributable to any other cause. It is possible that S. stercoralis may cause some degree of anemia in man. The amount is indeterminable in this region among hospital cases on account of the associated hookworm disease or malaria. Portals of entry for various micro5rganisms are made by the female mother worm and her larvae in the small intestine, and, while no case of general bacterial infection has been proved to have arisen in this way, its occurrence is possible and highly probable. In the cultures of strongyloides of man, there is among natives, who presumably are infected with purely tropical strains, a very marked predominance of development by the indirect or sexually differentiated mode, in some cases, an absolutely pure culture of the indirect mode larvae being obtained. There are, however, natives, cultures from whose stools contain from a single filariform larva of the direct phase up to a very definite predominance of this mode. Cultures from natives of the temperate zones contain a marked predominance of the direct phase larvae. The presence of the filariform (direct mode)larva is perhaps best accounted for by its being an attempt at' more perfect parasitism (Stiles). © 1911, Rockefeller University Press., All rights reserved.