1991 Volume 44 Issue 4 Pages 313-318
To examine the safety and immunogenicity of an attenuated strain of Getah virus, 3-day-old and 2-to 3-month-old piglets, and pregnant sows were inoculated with the attenuated KB/VT strain which had been established from the field 2078 strain of Getah virus by serial passages at 30°C in Vero cell cultures.
The KB/VT strain induced neither clinical abnormal signs nor viremia in any animals inoculated with the KB/VT strain, while the field 2078 strain induced viremia.
The 3-day-old piglets which were inoculated subcutaneously or intracerebrally with the KB/VT strain or the 2078 strain were subjected to the recovery of virus from the organs. The viruswas recovered from limited organs such as the lungs, spleen and lymph nodes of the piglets inoculated with the KB/VT strain and furthermore, the amount of the recovery virus from these organs was smaller than that from the piglets inoculated with the 2078 strain. The pregnant sows which had been inoculated with the KB/VT strain naturally gave normal birth. HI antibodies against Getah virus were detected in all of pigs inoculated with the KB/VT strain.
These results showed that the attenuated strain has satisfactory properties of safety and immunogenicity as live vaccine.