Live vaccine to getah virus infectious disease, and trivalent live vaccine to Japanese encephalitis virus, porcine parvovirus and getah virus infectious diseases

摘要

A trivalent live vaccine to Japanese encephalitis virus, porcine parvovirus and Getah virus infectious diseases, which comprises a mixture of (i) a live vaccine to Getah virus infectious disease as created by cultivating an attenuated Getah virus KB/VT strain, as obtained by continuous serial passages of a virulent Getah virus strain in Vero cells to 70 generations at 30°C followed by two times cloning by a plaque method to get purified virus, to HAL cells in such a way that the multiplicity of infection (amount of inoculated viruses/number of cells) is about 0.1; adsorbing the viruses to the cells for 60 minutes at 37 °C; then removing the inoculated viral fluid from the cells; adding a culture medium for cultivation of the viruses thereto; incubating the cells for 48 to 72 hours at 30°C; and, after the cytopathic effect (CPE) has been confirmed to progress to the middle degree or more, collecting the culture medium fluid to obtain an intended living vaccine to Getah virus infectious disease, (ii) a viral fluid as obtained by inoculating an attenuated Japanese encephalitis virus m strain to HmLu-1 cells as admitted to be suitable for propagation of the attenuated Japanese encephalitis virus m strain therewith, and (iii) a viral fluid as obtained by inoculating an attenuated porcine parvovirus HT⁻ /SK strain to swine kidney culture cells as admitted to be suitable for propagation of the attenuated porcine parvovirus HT⁻ /SK strain therewith, in such a proportion that the viral content in each viral fluid in the mixture is almost the same.