Tosh Chakradhar, Nagarajan Shanmugasundaram, Kumar Manoj, Murugkar Harshad V, Venkatesh Govindarajulu, Shukla Shweta, Mishra Amit, Mishra Pranav, Agarwal Sonam, Singh Bharati, Dubey Prashant, Tripathi Sushil, Kulkarni Diwakar D
ICAR-National Institute of High Security Animal Diseases, Bhopal 462 022, India.
ICAR-National Institute of High Security Animal Diseases, Bhopal 462 022, India.
Infect Genet Evol. 2016 Sep;43:173-8. doi: 10.1016/j.meegid.2016.05.012. Epub 2016 May 10.
Highly pathogenic avian influenza (HPAI) H5N1 viruses are a threat to poultry in Asia, Europe, Africa and North America. Here, we report isolation and characterization of H5N1 viruses isolated from ducks and turkeys in Kerala, Chandigarh and Uttar Pradesh, India between November 2014 and March 2015. Genetic and phylogenetic analyses of haemagglutinin gene identified that the virus belonged to a new clade 2.3.2.1c which has not been detected earlier in Indian poultry. The virus possessed molecular signature for high pathogenicity to chickens, which was corroborated by intravenous pathogenicity index of 2.96. The virus was a reassortant which derives its PB2 gene from H9N2 virus isolated in China during 2007-2013. However, the neuraminidase and internal genes are of H5N1 subtype. Phylogenetic and network analysis revealed that after detection in China in 2013/2014, the virus moved to Europe, West Africa and other Asian countries including India. The analyses further indicated multiple introductions of H5N1 virus in Indian poultry and internal spread in Kerala. One of the outbreaks in ducks in Kerala is linked to the H5N1 virus isolated from wild birds in Dubai suggesting movement of virus probably through migration of wild birds. However, the outbreaks in ducks in Chandigarh and Uttar Pradesh were from an unknown source in Asia which also contributed gene pools to the outbreaks in Europe and West Africa. The widespread incidence of the novel H5N1 HPAI is similar to the spread of clade 2.2 ("Qinghai-like") virus in 2005, and should be monitored to avoid threat to animal and public health.
高致病性禽流感(HPAI)H5N1病毒对亚洲、欧洲、非洲和北美的家禽构成威胁。在此,我们报告了2014年11月至2015年3月期间在印度喀拉拉邦、昌迪加尔和北方邦从鸭和火鸡中分离出的H5N1病毒的分离及特征。血凝素基因的遗传和系统发育分析确定该病毒属于一个新的2.3.2.1c分支,此前在印度家禽中未检测到。该病毒具有对鸡高致病性的分子特征,静脉致病性指数为2.96证实了这一点。该病毒是一种重配体,其PB2基因源自2007 - 2013年在中国分离的H9N2病毒。然而,神经氨酸酶和内部基因属于H5N1亚型。系统发育和网络分析显示,该病毒在2013/2014年在中国被检测到后,传播到了欧洲、西非和包括印度在内的其他亚洲国家。分析进一步表明H5N1病毒多次传入印度家禽并在喀拉拉邦内传播。喀拉拉邦鸭群中的一次疫情与从迪拜野生鸟类中分离出的H5N1病毒有关,表明病毒可能通过野生鸟类迁徙传播。然而,昌迪加尔和北方邦鸭群中的疫情源自亚洲一个未知来源,该来源也为欧洲和西非的疫情贡献了基因库。新型H5N1高致病性禽流感的广泛发生与2005年2.2分支(“青海样”)病毒的传播相似,应进行监测以避免对动物和公共卫生造成威胁。