Jahangir Alam, Ruenphet Sakchai, Shoham Dany, Okamura Masashi, Nakamaura Masayuki, Takehara Kazuaki
Laboratory of Zoonoses, School of Veterinary Medicine, Kitasato University, 35-1 Higashi 23, Towada-shi, Aomori 034-8628, Japan.
Virus Res. 2009 Nov;145(2):329-33. doi: 10.1016/j.virusres.2009.07.015. Epub 2009 Jul 25.
Intercontinental movements of northern pintail (Anas acuta) ducks wintering in Japan create a high-risk of both incursion and dispersion of avian influenza viruses (AIVs) that circulate in the ducks' breeding grounds in Siberia and Alaska. This predisposition is likely amplified by bi-directional conveyance of AIVs between Japan and China. In this study, H5N2 viruses were characterized by means of HA cleavage site sequencing and found to be low pathogenic. Through entire genome analysis, as well as in ovo and in vitro pathogenicity tests, one isolate - A/northern pintail/Akita/714/06 H5N2 (Akita/714/06 H5N2) - was characterized. Comparative molecular analysis revealed that genes of this virus have 97.5-99.6% and 96.7-100% likeness at nucleotide and at amino acid level, respectively, with genes of different subtypes of viruses isolated from China, Korea, Russia, and Italy. Phylogenetically, Akita/714/06 (H5N2) clustered with viruses isolated from Eurasian countries. Partial affinity to a recent Korean porcine strain is noticeable. Related evolutionary, ecological, and phenotypic aspects were discussed, thereby signifying the importance of the described pathogen-host-ecosystem interfaces.
在日本越冬的尖尾鸭（Anas acuta）的洲际迁徙，使得在其西伯利亚和阿拉斯加繁殖地传播的禽流感病毒（AIVs）有入侵和扩散的高风险。日本和中国之间AIVs的双向传播可能会加剧这种易感性。在本研究中，通过HA裂解位点测序对H5N2病毒进行了特征分析，发现其致病性较低。通过全基因组分析以及在鸡胚内和体外致病性试验，对一株分离株——A/尖尾鸭/秋田/714/06 H5N2（秋田/714/06 H5N2）进行了特征分析。比较分子分析显示，该病毒的基因在核苷酸水平和氨基酸水平上分别与从中国、韩国、俄罗斯和意大利分离的不同亚型病毒的基因有97.5 - 99.6%和96.7 - 100%的相似性。在系统发育上，秋田/714/06（H5N2）与从欧亚国家分离的病毒聚类。与最近的一株韩国猪病毒株有明显的部分亲缘关系。讨论了相关的进化、生态和表型方面，从而表明了所描述的病原体 - 宿主 - 生态系统界面的重要性。
