Sobre o comportamento de duas linhagens de Schistosoma mansoni Sambon 1907: proposição para método de estudo quantitativo

Abstract

Depois de tecerem comentários sobre as relações parasito-hospedeiro, os autores propõem um método para o estudo quantitativo de duas linhagens de Schistosoma mansoni. Após a proposição do método e sua aplicação, os autores concluem que a linhagem mineira de S. mansoni é mais patogênica do que a linhagem paulista do mesmo trematódeo.After the commentaries made of host parasitic relations, the authors suggest method for the study of two strains of Schistosoma mansoni. With the rnethod proposed and its experimental use, the authors concluded. For both strains of S. mansoni, the average number of adult worms found m the host was 60 days after infection correlating positively with the number of cercarme whirh the host were exposed to. For both strains there was a positive correlation between the number of adult parasites found in the hosts 60 days after infection and the number of liver granuloma of the same hosts. For both the Belo Horizonte strain as to the São José dos Campos strain, a negative correlation was found between the number of liver granuloma and the average percentage of host survival. Over a certain number of adult parasites present, there was a significant percentual number of granuloma on the infected mice with the Belo Horizonte strain. Within limits there was a smaller significant percentual survivat of mice infected with the Belo Horizonte strain. For the same number of granuloma, survivat was not significantly different between infected host, by one or the other strain, therefore it is suggested that the hypothesis most likely, is that the pathogenecity of the Belo Horizonte strain results from larger number of granuloma per adult female present. Within the limits established for the host survival index and number of parasites, the band of the degree of pathogenecity ab keeps within close limit of each other for the two strains. Although for the São José dos Campos strain the number os parasites after the experiment was significantly greater, concluding that a smaller number of Beto Horizonte worms caused on the mice used in the experience, similar levels of pathogenecity and mortality, than a larger number of São José dos Campos worms.