Ciclo Vital de Schistosoma mansoni através do Holochilus brasiliensis (Desmarest, 1818) em ambiente semi-natural (Trematoda, Shistosomatidae; Rodentia, Cricetidae)

Abstract

Junto ao Lago da Pampulha, Belo Horizonte, MG,

Uma Revisão Sobre a Participação Do Rato D’água Nectomys Squamipes Na Dinâmica De Transmissão Da Esquistossomose Mansônica: Um Estudo Multidisciplinar De Longo Prazo Em Uma Área Endêmica

“…como reservatório de S. mansoni foi demonstrada não só por hospedar parasitas adultos, mas também por eliminar ovos maduros em suas fezes (Dias et al 1978). Carvalho et al (1976) conseguiram fechar o ciclo do S. mansoni sem direta participação humana em condições semi-naturais, utilizando indivíduos de H. brasiliensis e Biomphalaria glabrata infectadas com uma cepa humana.…”

An ecological field study of the water-rat Nectomys squamipes as a wild reservoir indicator of Schistosoma mansoni transmission in an endemic area

“…Among the extra-human definitive hosts of this parasite, rodents of the genera Nectomys and Holochilus are the most probable wild reservoirs taking into account: (1) their semiaquatic habits (Ernest & Mares 1986), which make them highly exposed to infection; (2) their wide geographic distribution (Bonvicino 1994) coincident with the distribution of schistosomiasis in Brazil; (3) presence of infected individuals in most of the endemic areas where they were investigated, despite of the low human prevalence -rodents frequently showing higher infection rates in relation to human populations (Rey 1993); (4) rodent tolerance to human presence, occurring near human dwellings. Several experimental studies also support the hypothesis that water-rats are probable wild reservoirs of S. mansoni, showing high susceptibility to infection (Borda 1972, Souza et al 1992, Maldonado Jr. et al 1994, Ribeiro et al 1998, somatic development hypertrophy of adult worms , elimination of viable eggs with high infectivity potential (Picot 1992), high infection persistence , low pathogenicity with efficient peri-ovular modulation and low tissue aggression (Silva & Andrade 1989), and ability to close the transmission cycle in semi-natural conditions (Antunes et al 1973, Carvalho et al 1976, Kawazoe & Pinto 1983. Infection of small mammals other than Nectomys and Holochilus by S. mansoni occurs only occasionally, especially in areas of high transmission levels.…”

The Role of Wild Rodents in the Transmission of Schistosoma mansoni in Brazil

“…The potentiality of Holochilus sp. to act as wild reservoir of S. mansoni was demonstrated by their ability to eliminate viable eggs in feces in a natural environment (Dias et al, 1978) and by their ability to complete the parasite cycle without human presence in semi-natural conditions, using Biomphalaria glabrata as an intermediary host (Carvalho et al, 1976). …”