吉林省林区蜱粒细胞无形体感染的调查

Investigation on the infection with Anaplasma phagocytophilum in ticks from the forest area in Jilin province of China

目的调查吉林省蜱粒细胞无形体感染。方法运用聚合酶链反应方法对吉林延边地区采集的蜱标本粒细胞无形体16S rRNA和gltA基因片段进行扩增及序列分析,将扩增序列与GenBank注册的基因序列进行比较,构建粒细胞无形体gltA基因进化树。结果共检测游离蜱427只,其中全沟硬蜱100只,森林革蜱327只,粒细胞无形体感染阳性率分别为4.00%和0.00%。寄生蜱感染阳性率2.9%。寄生蜱与游离蜱感染率差别无显著性。16S rRNA序列与我国已在GenBank注册的AF205140序列一致,与国外粒细胞无形体16S rRNA序列存在不同程度的差异,相似性为97%～99%;gltA基因与GenBank的粒细胞无形体gltA基因片段比较,相似性为87%～97%,推导的氨基酸序列相似性为84%～99%。结论我国吉林省林区存在蜱粒细胞无形体感染。

To investigate the prevalence of the Anaplasma phagocytophilum in ticks from the forest area in Jilin province of China, 16S rRNA and gltA gene fragment of A. phagocytophilum in ticks collected from these area were amplified with PCR and followed by sequence analysis. In addition, the sequences of 16S rRNA and gltA gene fragment amplified from tick specimens were compared with the corresponding parts of the sequences deposited in GenBank. As a whole, a total of 427 hostseeking ticks were tested, including 100 Ixodes persulcatus and 327 Dermacentor silvarum, with the positive rates to discover A. phagocytophilum of 4% and 0% respectively. Besides, 2 out of 69 ticks were also found to be positive for parasites （2.9 %）, which included one nymphal D. silvarum. In comparison with the corresponding parts of A. phagocytophilum strains found in America, Sweden and South Korea, the detected 16S rRNA gene （1442 bp） was different at 3-6 bps. The similarities of the nucleotide sequences and the putative amino acid sequences of gltA gene with those deposited in GenBank were 87 %-97 % and 84-99% respectively. It is concluded that the infection with A. phagocytophilum is demonstrated for the first time in ticks from the forest area of Jilin province of China.