| abstract |
The present invention relates to methods for producing RNA virus cDNA, methods for producing viable, RNA virus and viable, RNA virus produced by those methods. The invention also related to a novel RNA virus cDNA, recombinant DNA molecules containing that cDNA and hosts transformed with those recombinant cDNA molecules. This invention further related to novel methods for screening for variants of a strain 3 poliovirus. This invention also related to methods for increasing the attenuation of a strain poliovirus. This invention provides a vaccine useful for immunizing a subject, for example a human, against infectious poliovirus, wherein the vaccine comprises an effective amount of an RNA virus, produced by transforming a suitable host cell with a recombinant nucleic acid sequence which encodes for the virus: culturing the host cell under conditions which permit the production of virus: and isolating the virus so produced, effective to immunize the subject, and a suitable carrier. Further provided to this invention is a method of immunizing a subject such as a human against infectious poliovirus, wherein the method comprises administering the subject a suitable dose of the vaccine described hereinabove. |