Natural infection of wild rodents by Schistosoma mansoni parasitological aspects
Mem. Inst. Oswaldo Cruz
; 87(supl.1): 271-6, 1992. tab, ilus
Article
in En
| LILACS
| ID: lil-116427
Responsible library:
BR15.1
RESUMO
The evaluation of the role of rodents as natural hosts of Schistosoma mansoni was studied at the Pamparräo Valley, Sumidouro, RJ, with monthly captures and examination of the animals. Twenty-three Nectomys squamipes and 9 Akodom arviculoides with a shistosomal infection rate of 56.5% and 22.2% respectively eliminated a great majority of viable eggs. With a strain isolated from one of the naturally infected N. squamipes, we infected 75% of simpatric Biomphalaria glabrata and 100% of albino Mus musculus mice. The adult worms, isolated from N. squamipes after perfusion were located mainly in the liver (91.5%) and the mesenteric veins (8.5%). The male/female proportion was 21. The eggs were distributed on small intestine segments (proximal, medial and distal portions) and the large intestine without any significant differences in egg concentration of these segments. In A. arviculoides, the few eggs eliminated by the stools were viable and there was litlle egg retention on intestinal segments. Considering the ease to complete S. mansoni biological cycle in the Nectomys/Biomphalaria/Nectomys system under laboratory conditions, probably the same is likely to occur in natural conditions. In support to this hypotesis there are also the facts that human mansonic shistosomiasis has a very low prevalence in Sumidouro and endemicity among the rodents has not changed even after repetead treatments of the local patients. Based on our experiments, we conclude that N. squamipes has become a natural host of S. mansoni and possibly may participate in keeping the cycle of schistosomiasis transmission at Pamparräo Valley
Full text:
1
Collection:
01-internacional
Database:
LILACS
Main subject:
Schistosoma mansoni
/
Trematode Infections
/
Arvicolinae
Type of study:
Risk_factors_studies
Limits:
Animals
Country/Region as subject:
America do sul
/
Brasil
Language:
En
Journal:
Mem. Inst. Oswaldo Cruz
Journal subject:
MEDICINA TROPICAL
/
PARASITOLOGIA
Year:
1992
Document type:
Article