云南西北部地区家畜无形体感染的分子流行病学调查

Molecular epidemiological investigation of Anaplasma in domestic in the northwest of Yunnan Province,China

目的了解云南省西北部地区家畜无形体感染状况,为人无形体病的防控提供科学依据。方法在云南省西北部地区15个县市采集部分家畜血液样本进行DNA提取,PCR扩增无形体16S rRNA基因片段;测定扩得基因片段DNA序列并对其做同源性比对,以确定无形体种类。结果共采集1791头牛、羊、犬、马、驴的血样,PCR扩增阳性503份,其中牛、羊和犬的阳性率分别为41.08%(228/555)、38.10%(240/630)、6.29%(35/556)。测定PCR扩增16S rRNA基因片段序列,序列同源性分析显示73株序列(14.51%)属嗜吞噬细胞无形体(Anaplasma phagocytophilum),226株序列(44.93%)属绵羊无形体(A.ovis),137株序列(27.24%)属边缘无形体(A.marginale),48株序列(9.54%)属血小板无形体(A.platys),16株序列(3.18%)属牛无形体(A.bovis),3株序列(0.60%)属山羊无形体(A.capra)。其中牛样本检出6种无形体,以边缘无形体为主;羊样本检出5种无形体,以绵羊无形体为主,未检测到山羊无形体;犬样本仅检出嗜吞噬细胞无形体。在15个县市中有12个县市的家畜样本检出无形体基因,盈江县阳性率最高(95.65%),主要是边缘无形体。对人致病的嗜吞噬细胞无形体基因分别从牛(30份)、羊(8份)、犬(35份)样本检出,对人致病的山羊无形体从3份牛样本检出,这2种人兽共患病原体感染的家畜主要分布于滇西北的德钦和香格里拉地区。结论云南省西北部地区部分县(市)无形体感染的家畜主要是牛、羊,其次是犬,无形体种类丰富,需加强当地人无形体病的防控。

To understand Anaplasma infection with domestic in the northwest of Yunnan and provide scientific evidence for developing control measures. A total of 1 791 blood samples of cattle, sheep, dogs, horses and donkeys were collected from 15 counties and cities in the northwest of Yunnan Province for DNA extraction, and 660 bp fragment of 16S rRNA was amplified. The positive products were sequenced. According to sequence homology comparison and genetic evolution analysis, the species of intangibles were determined, and epidemiological analysis was carried out based on sample data. Blood samples were collected and 503 of them are detected to the Anaplasma. The positive rates of cattle, sheep and dogs were 41.08% (228/555), 38.10% (240/630) and 6.29% (35/556), respectively. Six kinds of intangibles were detected: A.phagocytophilum (14.51%, 73/503), A.ovis (44.93%, 226/503), A.marginale (27.24%, 137/503), A.platys (9.54%, 48/503), A.bovis (3.18%, 16/503), A.capra (0.60%, 3/503), mainly A.ovis. A.marginale (75/228), A.ovis (216/240), A.capra and A.phagocytophilum were detected in bovine blood, sheep blood and dog blood respectively in 12 of 15 counties and cities. The highest positive rate of domestic of 95.65% was found in Yingjiang County, mainly due to the high infection of cattle with A.marginale. At present, 73 cases of A.phagocytophilum, including cattle (30), sheep (8) and dogs (35), have been identified, mainly distributed in Deqin (47)and Shangri La (16) areas in Northwest Yunnan, and 3 cases of A.capra have been detected in the blood of cattle in this area. In conclusion Anaplasma was endemic in domestic animals such as cattle,sheep and dog in some counties of the northwest, Yunnan Province, and the pathogen species are rich, so it is necessary to strengthen prevention for human infection with Anaplasma disease.