摘要:
A safer live smallpox vaccine, which contains a lowered content of revertants, is provided. A process for manufacturing a live smallpox vaccine which comprises steps of: inoculating a master seed solution of an attenuated vaccinia virus to an appropriate number of containers (1 to n wherein n is an integer) of rabbit kidney cells and incubating them; inoculating a portion of the cultured solution obtained from each container to RK-13 cells and to Vero E6 cells and incubating them to thereby select containers which contain a cultured solution that forms plaques in RK-13 cells but not in Vero E6 cells; and preparing a drug substance of vaccine using the aforementioned cultured solution (working seed solution), and a live smallpox vaccine prepared in the aforementioned process.