Data_Sheet_1_Etiologic characteristics of avian influenza H11 viruses isolated from the live poultry market in southeast coastal region in China.docx

Since it was first identified in 1956, the H11 subvariant influenza virus has been reported worldwide. However, due to the low pathogenicity of the H11 subvariant and the absence of its widespread transmission among humans, there are only a few reports on the etiology of the H11 subvariant influenza virus. Therefore, in the present study, we isolated a strain of the H11N3 avian influenza virus (AIV) from poultry feces from the live poultry market in the southeast coastal region of China. Considering that the H11 subvariant is known to cause infections in humans and to enrich the knowledge of the H11 subvariant of the avian influenza virus, the genetics, pathogenicity, and transmissibility of the isolate were studied. The phylogenetic analysis indicated that the H11N3 isolate was of Eurasian origin and carried genes closely related to duck H7N2 and H4N6. The receptor binding analysis revealed that the H11N3 isolate only acquired a binding affinity for avian-derived receptors. In the respiratory system of mice, the isolate could directly cause infection without adaptation. In addition, the results from transmission experiments and antibody detection in guinea pigs demonstrated that H11N3 influenza viruses can efficiently transmit through the respiratory tract in mammalian models. Direct infection of the H11N3 influenza virus without adaptation in the mouse models and aerosol transmission between guinea pig models confirms its pandemic potential in mammals, underscoring the importance of monitoring rare influenza virus subtypes in future studies.

自1956年首次被发现以来，H11亚型流感病毒（H11 subvariant influenza virus）已在全球范围内被多次报道。然而，由于该H11亚型病毒的低致病性，且未在人群中发生广泛传播，目前针对H11亚型流感病毒病原学的研究报道较为有限。因此，本研究从中国东南沿海地区活禽市场的家禽粪便中，分离得到一株H11N3亚型禽流感病毒（avian influenza virus, AIV）。鉴于H11亚型已知可感染人类，且为丰富H11亚型禽流感病毒的相关研究认知，本研究对该分离株的遗传学特性、致病性及传播能力进行了系统研究。系统发育分析结果显示，该H11N3分离株属于欧亚进化谱系，其携带的基因与鸭源H7N2及H4N6亚型病毒亲缘关系密切。受体结合分析表明，该H11N3分离株仅对禽类来源的受体具备结合亲和力。在小鼠呼吸系统中，该分离株无需适应性传代即可直接引发感染。此外，豚鼠传播试验与抗体检测结果证实，H11N3流感病毒可在哺乳动物模型中通过呼吸道实现高效传播。该H11N3毒株无需适应性传代即可直接感染小鼠模型，且可在豚鼠模型中发生气溶胶传播，这一结果证实了其在哺乳动物中具备大流行潜力，凸显了未来研究中对罕见流感病毒亚型开展监测的重要性。