Abstract:This study aimed to perform genome feature analysis of rabies viruses obtained in three recent years, and to analyze epidemiology in humans in Yunnan from 2008 to 2018 through descriptive epidemiology methods. Samples of brain tissues from humans and other animals were analyzed with a direct immunofluorescence assay (DFA). Positive samples were subjected to nucleicacid extraction and reverse transcription, then reverse transcription-polymerase chain reaction (RT-PCR) with specific primers for the viral nucleoprotein (N) and glycoprotein (G) genes. Sequencing and phylogenetic analysis were performed with molecular biology software. A total of 828 rabies deaths were identified in Yunnan from 2008 to 2018, and the incidence rate fluctuated from 0.046/10 000 to 0.285/10 000. The rabies incidence rate decreased through these 11 years, and the incidence occurred year round, especially in summer. The affected population was mainly peasants, and all age groups were affected. Previously, 14 districts have reported rabies cases; however, there are 16 districts in Yunnan. The epidemic situation in the classical epidemic areas of Wenshan and Honghe remains severe, and the affected area is expanding each month. After RT-PCR identification of 46 positive DFA samples, we obtained 34 N genes and 33 G genes. The YN-A evolution cluster was identified for the N genes and G genes through phylogenetic analysis, and the genes were close to six strains from Sichuan Province in the cladogram. The 34 strains’ N genes had nucleotide acid and amino acid similarity of 99.2%~100% and 99.1%~100%, respectively. The 33 strains’ G genes had nucleotide acid and amino acid similarity of 98.5%~100% and 98.7%~100%, respectively. Although rabies remains prevalent in Yunnan, the epidemic situation is decreasing, and the epidemic area is expanding. Thus, more attention should be paid to the newly affected areas while conventional surveillance is carried out in the classical epidemic areas. YN-A of RABV is the predominant strain in Yunnan. The YN-A evolution cluster of 34 N genes and 33 G genes was identified in phylogenetic analysis, and the genes and genome type I RABV were in the same cluster in the cladogram.
杨卫红, 杨鹤飞, 冯云, 章域震, 潘虹, 王娟. 云南省2008-2018年人间狂犬病流行特征及狂犬病病毒基因分析[J]. 中国人兽共患病学报, 2021, 37(4): 339-345.
YANG Wei-hong, YANG He-fei, FENG Yun, ZHANG Yu-zhen, PAN Hong, WANG Juan. Epidemiology of rabies in human and genome analysis of rabies virus of Yunnan Province from 2008 to 2018. Chinese Journal of Zoonoses, 2021, 37(4): 339-345.