. Animal parasites and human disease. Medical parasitology; Insects as carriers of disease. 308 PILARIS AND THEIR ALLIES it is confined to regions of heavily forested tropical swamps. In some districts in Uganda it has been found in 90 per cent of the inhabitants. The microfilariae of this species (Fig. 124B) are smaller than those of F. bancrofti, have a blunt tail and lack the sheath which is so characteristic of F. bancrofti. Fur- thermore they show no tendency to disappear periodically from the peripheral vessels. The adult worm, which has rarely been found, is smaller than F. bancrofti (a
. Animal parasites and human disease. Medical parasitology; Insects as carriers of disease. 308 PILARIS AND THEIR ALLIES it is confined to regions of heavily forested tropical swamps. In some districts in Uganda it has been found in 90 per cent of the inhabitants. The microfilariae of this species (Fig. 124B) are smaller than those of F. bancrofti, have a blunt tail and lack the sheath which is so characteristic of F. bancrofti. Fur- thermore they show no tendency to disappear periodically from the peripheral vessels. The adult worm, which has rarely been found, is smaller than F. bancrofti (about three inches in length) and occurs in the connective tissue of the abdominal and peri- cardial cavities. The normal transmitting agent, probably some species of mosquito, is not certainly known. No disease symp- toms which can be correlated with the presence of the parasite have yet been demonstrated. Another species, F. juncea (demarquaii), of which the larva (Fig. 124D) is small and without a sheath, as in F. perstans, but with a sharp tail, occurs in the West Indies and northern South America. It is not known to cause any diseased conditions. The adults live in the mesenteric tissues. In many Indians in British Guiana F. perstans and F. juncea occur together in the blood, and in some cases the presence of F. bancrofti compH- cates the matter still more. F. magalhaesi is another species about which very little is known. A pair of adult worms were found only once, in the heart of a child in Rio de Janeiro. They were of unusually large size, the female measuring over six inches in length and the male about three and a half inches. Nothing is known of the life history or pathological effects. The Loa Worm. — Of somewhat different nature from the above species of Filaria is F. loa or Loa loa (Fig. 128), a parasite found on loa^'worms,' ffmaie ^^'^^ ^^^^ ^oast of Africa, especially in Congo, (9) and male ($). Avhich, as an adult, creeps in the connective Loorj^t ^''''' *^'^
Size: 1364px × 1832px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., book, bookcentury1900, bookdecade1910, bookpublishernewyorkjwiley
