Abstract
Cultivation of Izumi-fever virus in tissue culture was attempted with various kinds of tissue, i.e., heart, lung and kidney of suckling mouse, rat, guinea pig, sand rat and human embryo, and chicke mbryonic skinmuscle and chorioallantoic membrane.
The cultivation of this virus was carried out through stational method in the medium consisting of Hanks' solution 60%, ultrafiltrate horse serum 30% and chick embryo extract 10%.
No cytopathogenic effects were observed in any case. Therefore, histopathological changes of rats sacrificed 30 days after inoculation with the culture fluid of the 3rd passage of tissue culture were investigated. The histopathological changes showed that this virus multiplied more favorably in heart and lung tissue than in kidney tissue throughout all species of animal used.
In developing hen's egg, yolk sac method and allantoic cavity method were used. In both cases, this virus failed to cause fetal infection, and no hemagglutination was observed. The histopathological changes of rats inoculated with egg material of serial passages, showed that yolk sac method was superior to allantoic cavity method to cultivate this virus.
