Molecular epidemiology of rabies in Guangxi Province, south of China

Background: Surveillance data for rabies in Guangxi Province in China showed that human rabies cases have gradually increased since 1996. Objective: To evaluate the epidemiology of rabies at the molecular level and provide suggestions for effective prevention of rabies in Guangxi. Studv design.- Since 2000. 1569 brains from suspected rabid animals were collected from different areas of Guangxi. Rabies virus was isolated from 42 samples. RT-PCR was used to amplify a 455 nucleoticle segment of the Y-terminal of the N gene. The sequencing data from that segment was used for phylogenetic analysis. Results: Nucleotide homology comparisons and phylogenetic tree analysis based on this sequence indicated that all the rabies virus isolates from Guangxi belonged to genotype I and could be divided into four groups. Groups 1, 11 and IV included 23, 10 and 8 isolates, respectively. These had nucleotide homologies of 97.1-100%, 98.2-100% and 99.1-99.6%, respectively. Only the GXN 119 strain belonged to group 111. Group I had two group-specific mutations: T90N and El 101). Group 11 had one group-specific mutation of T42S. Conclusions: This study showed that rabies virus isolates from Guangxi have a close genetic relationship and topographical distribution. (c) 2007 Elsevier B.V. All rights reserved.