Genetic characteristics of field and attenuated rabies viruses ... - Evira

group including some reference viruses from Europe was further divided into four
subgroups. All the vaccine strains were clearly different from the field strains. No
recombination between the field and vaccine virus strains was observed. The critical
roles of geographical isolation, the limitation of the genetic clustering, and the evolution of
the rabies virus were shown during this study.
The rabies virus vaccine strain RV-97 is widely used in Russia as a component of
the oral anti-rabies vaccine “Sinrab”. To characterize the molecular properties of this
strain, entire genome sequencing was conducted. A simple technique was developed to
obtain this sequence, including the 3’- and 5’- ends. The entire genome sequence and
deduced amino-acid sequences of the major viral proteins were compared with the
sequences of other known fixed rabies viruses. The strain RV-97 formed a separate
phylogenetic branch and seems to be more related to the group of Japanese strains. The
field strains from the Caucasian group seem to be phylogenetically the nearest group to
the RV-97 strain.
The data shown herein makes it possible to develop molecular methods for
distinguishing between the field rabies viruses from the vaccine strains for the rapid
recognition of the vaccine strains that are unstable or have reverted back to their
pathogenic form. The wide genetic heterogeneity verified in this study indicates that it is
important to remain on permanent alert for the appearance of rabies.
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