Characteristics of a Fixed Rabies Virus Cultivated on Developing Chick Embryos

Summary

After 47 passages through the developing chick embryo, rabies fixed virus shows no enhanced virulence for the chick embryo, as judged by the complete development of the embryo, the relatively low virus titre in the embryo brain and the scanty pathological changes in the brain. The virulence of the chick embryo passage virus for mice and guinea pigs remained unchanged, while that for rabbits appeared reduced considerably, as demonstrated by the prolonged incubation period, and duration of the infection. The specific anti-genic character of the chick embryo virus remained unchanged during 47 passages over a period of 18 months.