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Objective@#To understand the epidemiologic features of the rabies in Xishuang banna prefecture of Yunnan province, China in 2008-2017 and the viral molecular-evolution characteristics.@*Methods@#The data of rabies case questionnaire were collected. The brain tissue samples from mad dogs, suspicious sick dogs and human brain tissue, saliva and cerebrospinal fluid samples from rabies patients were collected in Xishuangbanna. Coding region of nucleoprotein and glycoprotein genes were amplified by RT-PCR and sequenced. Homology and phylogenetic analysis were performed using the relevant bioinformatics software.@*Results@#A total of 62 cases of human rabies were occurred in 28 districts of the 3 counties, Xishuangbanna prefecture in 2008-2017. Of them, 37 cases in Jinghong county, 15 in Menghai county and 10 in Mengla county. In which 48 cases were bitten by domestic dogs (77.42%), 11 cases were bitten by wild dogs (17.74%). Rabies case was occurred every year in the past decade. The seasonal incidence was not obvious. The majority of patients were aged from 30 to 59 years-old, with the youngest 1 year-old and the eldest 91 year-old. The male to female ratio was 1.70∶1, most cases were farmers. The nucleotide sequences of nucleoprotein gene of 9 virus strains (7 from Jinghong, 1 from Menghai and 1 from Mengla) were obtained from the samples of dogs and patients. Homology and phylogenetic analyses indicated that the 5 strains belonged to clade China-Ⅰ, 3 clade China-Ⅱ and 1 clade China-Ⅵ. The nucleotide sequences of glycoprotein gene of 5 virus strains (3 from Jinghong, 1 from Menghai and 1 from Mengla) were obtained from these positive samples, and all were clade China-Ⅰ, it is same with nucleoprotein genes analysis result from these 5 virus strains. These China-Ⅰ and China-Ⅱ strains from Xishuangbanna have a closer genetic relationship with same clade strains isolated from Pu’er and other prefectures of Yunnan province as well as Sichuan, Guizhou and Guangxi. The China-Ⅵ strain from Xishuangbanna share high homology and genetic relationship with China-Ⅵ strains isolated from southwestern Yunnan and neighbouring countries such as Myanmar, Laos and Vietnam in recent years.@*Conclusions@#In Xishuangbanna, rabies mainly occurred in rural area and domestic dog was the main source of transmission. These RABV clades China-Ⅰ, China-Ⅱ and China-Ⅵ were found in this region and the China-Ⅰ was principal clade. The transmission source of China-Ⅰ and China-Ⅱ were from adjacent areas in the province and China-Ⅵ was from Myanmar and Laos.
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ABSTRACT:In recent years ,there has been high prevalence of murine typhus in Yunnan Province ,People's Republic of China .A large outbreak of murine typhus occurred in Xishuangbanna Prefecture ,Yunnan Province in 2010 .However ,not all cases were confirmed by laboratory assays ;therefore ,field epidemiologic and laboratory investigations of murine typhus in Xishuangbanna Prefecture were conducted in 2011 .Blood samples were collected from clinical diagnostic cases at the acute and convalescence stages of murine typhus in Xishuangbanna Prefecture ,Yunnan Province ,from June to September of 2011 ,and blood and spleen samples were collected from mice sharing the same habitats as the patients .Immunofluorescence assays were used to test for the presence of IgM and IgG antibodies against Rickettsia typhi in sera from patients and mice .Real‐time PCR was used to detect the groEL gene of R .typhi in blood clots from patients at the acute stage and in spleen tissue from mice .A total of 1 157 clinically diagnosed murine typhus cases occurred in Xishuangbanna Prefecture ,Yunnan Province in 2011 ,with an incidence of 102 .10/100 000 .Of these cases ,80 were investigated by laboratory assays and 74 of 80 patients were confirmed to have murine typhus .The coincidence rate between the clinical diagnosis and laboratory detection was 92 .50% .The positivi‐ty rate for IgG antibodies against R .typhi was 14 .0% (14/100) for Rattus f lavipectus ,while the rate by PCR was 9 .0%(9/100) .That laboratory diagnoses confirmed that the severity of the murine typhus outbreak in Xishuangbanna cannot be ig‐nored .The distribution of host animals transmitting R .typhi underscores this conclusion .