Phylogenetic Analyses Of The Rabies Viruses Isolated From Inner Mongolia Autonomous Region Over The Period Of The Year 2009 To 2012

Rabies is a severe zoonosis which caused by Rabies virus and its death rate is almost 100%. The Inner Mongolia Autonomous Region had been for years experienced occasional human rabies cases where the reported cases increased to more than 30 cases of animal rabies infection from 2007 to 2014, even reached to 12 cases in 2011. In this study, we collected a total of 22 samples of animal brain tissue from 2009 to 2012 in the Inner Mongolia Autonomous Region. The collected sampels were detected by RT-PCR and 16 of 22 samples were identified positive. Then by inoculating BALB/c mouse, we isolated 16 Rabies virus isolates.Through RT-PCR and sequencing we obtained 16 complete sequences of these isolates. Phylogenic analysis based on the sequences of N genome, G genome and complete genome showed that the isolates belong to the Genotype I. Of which 12 isolates were classified into the Asian lineage and other 4 isolates (NM5, NM8, NM13 and NM16) belonged to the Cosmopolitan lineage.We speculated that the two major lineages made up the Inner Mongolia major rabies epidemic lineages.The 12 isolates of Asian lineages had closed related with BeijingHul, Shananxi-BZ-6, HeBeiO from Neighboring provinces and the nucleotide similarity of N genome was as high as 98.8%-99.9%. The other 4 isolates of Cosmopolitan lineages were closed related with Mongolia 3 (Mongolia) and 3502f (Russia) and the nucleotide similarity of N genome was as high as 99.0%-99,1%and 97.8%-98.0%, respectively.The five structure protein coding region size, functional motif and functionally important sites within the 16 isolates were conservative, but some sites still occurred amino acid mutations. The length of N-P noncoding region and P-M noncoding region were different in the 16 isolates. N-P noncoding region and P-M noncoding region length of 12 isolates belong to the Asian lineages were 91 nt and 87 nt, respectively. N-P noncoding region and P-M noncoding region of 4 isolates belong to cosmopolitan lineages were 90 nt and 88 nt, respectively. The N protein of NM11, CNM12, NM14 and NM15 isolates lost phosphorylation site in 375th site owing to Thr (Lys) mutation. Comparison of the G protein main antigenic sites between the 16 isolates and vaccine strains indicated that the 12 isolates belonged to Asian lineage had V332I mutation in site â…¢ and the 4 isolates belonged to Cosmopolitan lineage had T36A mutation in site â…¡.ERA (Cosmopolitan lineage) vaccine were able to provided completely protection for the BALB/c mice when challenged with either the isolate NM4 (Asian lineage) or NM8 (Cosmopolitan lineage). In conclusion, the current vaccines still have the abilities to effectively protect the animals against RABV infection.In this study, we made single genes and whole genome analysis of the genetic variation of the rabies virus in Inner Mongolia, and analyzed and studied the current vaccine immune protective effect for the formulation of rabies prevention and control measures to provide a scientific basis for ensuring human health and public health security.In this study, we analyzed the variation of the rabies virus in the Inner Mongolia on the level of single genes and complete genome. We also analyzed the immune protective effect of the current vaccine on these isolates. These results will provide a scientific reference for rabies prevention and public health ensurance.