Detection and molecular characterization of rabies virus in Mongolia during 2008-2010

Abstract

Aim: We aimed to investigate the prevalence and molecular characterization of rabies virus (RABV) from wild and domestic animals in Mongolia during 2008-2010. Materials and Methods: Brain tissue samples were collected from 24 rabid animals in Zavkhan, Omnogovi, Tov, Dundgovi, Govi-Altai, Selenge, Ovorkhangai, and Khentii provinces in Mongolia. Herein, samples were included from 13 domestic animals (dogs, cattle, camels, sheep, and goat) and 11 wild animals (wolves and foxes) in this study. Direct fluorescent antibody (DFA) test and reverse transcriptase polymerase chain reaction (RT-PCR) were performed for detection of RABV, and positive samples were further processed for molecular characterization of the virus using nucleoprotein gene. Subsequently, the molecular characterization was determined based on the nucleoprotein gene. Results: Out of 24 samples, 22 samples were detected positive for RABV by DFA test, and its nucleoprotein gene was amplified in all of the 24 samples by RT-PCR. These Mongolian RABVs were classified within steppe-type virus clade by phylogenetic analysis of nucleoprotein gene sequences. This steppe-type virus clade was clearly divided by two Sub-clades (A and B). The most of Mongolian RABVs belongs to the Sub-clade A in the phylogenetic tree. Conclusion: These findings have clearly confirmed RABV in domestic and wild animals of Mongolia. Further molecular characterization indicated that this Mongolian strain is steppe-type virus clade consisting of two sub-clades; the Subclade A might be prevalent in Altai, Khangai, Khentii Mountains as a major genotype, whereas the Subclade B seems to be cosmopolitan in the steppe-type virus clade, is spread in northern central Eurasia.

Keywords

• detection
• molecular characterization
• Mongolia
• rabies virus
• sub-clade A
• subclade B