H7N9 found in live poultry

Scientists have detected a similarity in the gene sequence of the H7N9 flu virus in humans and that of H7N9 found in live poultry, the China Academy of Agricultural Sciences (CAAS) said.

从中国农业科学院获悉，该院哈尔滨兽医研究所陈化兰科研团队经过连续作战，最新得出的研究结果表明：在我国导致人感染的新型H7N9流感病毒与同一时期存在于活禽市场上的H7N9禽流感病毒高度同源，在国际上首次从病原学角度揭示了新型H7N9流感病毒的来源，为我国科学防控H7N9禽流感提供了重要依据。

Studies, carried out by CAAS Harbin Veterinary Research Institute, found that the H7N9 flu virus is a combination of genes from various viruses, a CAAS statement said.

研究结果表明，新型H7N9流感病毒是不同来源病毒的重组病毒，它的6个内部基因来源于H9N2禽流感病毒，而血凝素(HA)和神经氨酸酶(NA)基因的来源尚不明确。研究发现，新型H7N9病毒的受体结合位点获得了部分人流感病毒特征的突变，病毒在感染人后获得了关键氨基酸位点的适应性突变，这些可能与该病毒对人的感染和致死能力有关。

In the H7N9 flu virus, six of its inner genes are from the H9N2 bird flu virus, but origins of both its hemagglutinin (HA) gene and neuraminidase (NA) gene are not clear, the statement said.

自从3月31日国家卫生和计划生育委员会公布了上海和安徽出现新型人感染H7N9流感病毒病例之后，哈尔滨兽医所科研团队连夜分赴各地开展监测，彻夜进行实验室诊断、病毒分离与基因序列比对。他们先后在上海、安徽的活禽市场和养殖场采集病原学样品970份，在分离自活禽市场采集的样品中，检测出20份H7N9禽流感病毒阳性，而所有养殖场样品的检测结果均为阴性。通过基因序列分析表明，H7N9禽流感病毒的各个基因片段，与H7N9人体分离株高度同源，证明了导致人感染和致死的H7N9流感病毒可能来源于同一时期家禽中的H7N9禽流感病毒。

Chen Hualan and Li Chengjun, researchers with the institute, headed the study。They collected 970 samples from live poultry markets and farms in Shanghai and Anhui. Twenty of the samples from the markets were positive and all samples from poultry farms were negative.

目前，该实验室正在积极评估已有储备的H7亚型禽流感病毒疫苗对新型H7N9禽流感病毒的免疫保护效果，同时加紧研制专门针对新型H7N9禽流感病毒的疫苗。

Further work should be carried out to detect H7N9 bird flu virus to explore its sources and transmission channels, Chen said。The research was published in the latest English version of Chinese Science Bulletin, which is sponsored by Chinese Academy of Sciences and National Natural Science Foundation of China.

陈化兰表示，在前期工作的基础上，下一步将加强H7N9禽流感病毒在家禽中的检测，查明病毒的来源和传播途径，开展H7N9病毒在动物模型中的致病性、传播能力及致病机理研究，为制定科学合理的防控措施提供理论依据。