H9N2亚型禽流感病毒与其他病原混合感染的研究进展

H9N2亚型禽流感病毒（Avian influenza virus，AIV）属于低致病性AIV，但因其分布广泛、传播迅速，可引起感染家禽生产性能下降，给家禽业带来了极大的经济损失。H9N2亚型AIV在感染家禽过程中可引起严重的免疫抑制，使家禽极易继发上呼吸道细菌、消化道细菌等感染，从而导致H9N2亚型AIV致病力增强，细菌黏附定植能力增强，家禽死亡率显著升高。另外，H9N2亚型AIV还能与禽传染性支气管炎病毒、禽传染性法氏囊病病毒、新城疫病毒等发生混合感染，病毒入侵时有可能出现协同作用或颉颃作用，从而相互促进或抑制病毒的复制和排毒；H9N2亚型AIV还极易发生突变或与其他亚型流感病毒在混合感染时发生基因重组产生感染人的新亚型毒株，给人类健康和公共卫生安全带来重大威胁。作者综述了H9N2亚型AIV与其他病原混合感染的研究进展，通过阐述H9N2亚型AIV与细菌或病毒混合感染的协同或颉颃作用，以期为临床上H9N2亚型AIV混合感染的防治提供参考。

Research Progress on Co-infection of H9N2 Subtype Avian Influenza Virus with Other Pathogens

H9N2 subtype Avian influenza virus (AIV) is a low pathogenic AIV. However, it is widely prevalent and spreads quickly, and can decline the performance of infected poultry, bringing great economic losses to the poultry industry. H9N2 subtype AIV can cause severe immunosuppression in the infected poultry, making it easier to be co-infection with upper respiratory tract bacteria and digestive tract bacteria. The co-infection with bacteria results in increasing of pathogenicity of H9N2 subtype AIV, and enhanced ability of bacterial adhesion and colonization, leading to a significant elevation in poultry mortality. Besides, H9N2 subtype AIV can co-infect with avian Infectious bronchitis virus, avian Infectious bursal disease virus, and Newcastle disease virus, etc., and there may be synergistic or antagonistic effects when the virus invades, thereby mutually promoting or inhibiting viral replication and shedding. Moreover, H9N2 subtype AIV is prone to mutation or genetic recombination with other subtypes of Influenza viruses to produce new influenza strains that may infect humans, posing a great threat to public health worldwide. This paper summarized the research advance of mixed infection of H9N2 subtype AIV and other pathogens. By expounding the synergistic or antagonistic effects between H9N2 subtype AIV and bacteria or other viruses, it is hoped to provide a reference for the prevention and treatment of H9N2 subtype AIV associated co-infection in the clinic.