Evolutionary Dynamics of Multiple Sublineages of H5N1 Influenza Viruses in Nigeria from 2006 to 2008
Evolutionary Dynamics of Multiple Sublineages of H5N1 Influenza Viruses in Nigeria from 2006 to 2008
复制标题
DOI：
10.1128/jvi.02385-09
复制
发表时间：
2010-04-01
影响因子：
5.4
通讯作者：
Cattoli, Giovanni
中科院分区：
文献类型：
--
作者：
Fusaro, Alice;Nelson, Martha I.;Cattoli, Giovanni
自2006年初以来，高致病性A/H5 N1禽流感（HPAI H5 N1）病毒严重影响了尼日利亚家禽业。以前的研究已经确定了该病毒多次引入尼日利亚和共循环谱系之间的几次重配事件。为了确定在尼日利亚共同传播的多个H5 N1谱系的空间、进化和种群动态，我们对2006年至2008年分离的106株HPAI H5 N1病毒的全基因组序列进行了系统发育分析，这些病毒代表了尼日利亚所有25个州和联邦首都直辖区（FCT）报告的疫情。我们在尼日利亚发现了一个主要的新的亚支，它在遗传学上与以前发现的所有亚系以及两个新的重配事件不同。对病毒地理分布的详细分析确定了尼日利亚高致病性禽流感H5 N1病毒的两个主要来源人群，一个在主要的商业家禽区（西南地区），另一个在尼日利亚北方，那里的野生鸟类和后院家禽之间经常接触。这些发现表明，来自东欧或俄罗斯的候鸟可能在高致病性禽流感H5 N1病毒传入尼日利亚方面发挥重要作用，但不能排除病毒通过家禽和家禽产品的流动传播。我们的研究为尼日利亚H5 N1流感病毒的起源和演变提供了新的见解，并对有针对性的监测工作具有重要意义，以快速确定病毒在尼日利亚境内的传播。
Highly pathogenic A/H5N1 avian influenza (HPAI H5N1) viruses have seriously affected the Nigerian poultry industry since early 2006. Previous studies have identified multiple introductions of the virus into Nigeria and several reassortment events between cocirculating lineages. To determine the spatial, evolutionary, and population dynamics of the multiple H5N1 lineages cocirculating in Nigeria, we conducted a phylogenetic analysis of whole-genome sequences from 106 HPAI H5N1 viruses isolated between 2006 and 2008 and representing all 25 Nigerian states and the Federal Capital Territory (FCT) reporting outbreaks. We identified a major new subclade in Nigeria that is phylogenetically distinguishable from all previously identified sublineages, as well as two novel reassortment events. A detailed analysis of viral phylogeography identified two major source populations for the HPAI H5N1 virus in Nigeria, one in a major commercial poultry area (southwest region) and one in northern Nigeria, where contact between wild birds and backyard poultry is frequent. These findings suggested that migratory birds from Eastern Europe or Russia may serve an important role in the introduction of HPAI H5N1 viruses into Nigeria, although virus spread through the movement of poultry and poultry products cannot be excluded. Our study provides new insight into the genesis and evolution of H5N1 influenza viruses in Nigeria and has important implications for targeting surveillance efforts to rapidly identify the spread of the virus into and within Nigeria.