Soda Kosuke, Kashiwabara Mina, Miura Kozue, Ung Trang T H, Nguyen Hang L K, Ito Hiroshi, Le Mai Q, Ito Toshihiro
Department of Joint Veterinary Medicine, Faculty of Agriculture, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8553, Japan.
Faculty of Agriculture, Avian Zoonosis Research Center, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8553, Japan.
Virus Genes. 2020 Dec;56(6):712-723. doi: 10.1007/s11262-020-01797-7. Epub 2020 Sep 29.
To date, avian influenza viruses (AIVs) have persisted in domestic poultry in wet markets in East Asian countries. We have performed ongoing virus surveillance in poultry populations in Vietnam since 2011, with the goal of controlling avian influenza. Throughout this study, 110 H3 AIVs were isolated from 2760 swab samples of poultry in markets and duck farms. H3 hemagglutinin (HA) genes of the isolates were phylogenetically classified into eight groups (I-VIII). Genetic diversity was also observed in the other seven gene segments. Groups I-IV also included AIVs from wild waterbirds. The epidemic strains in poultry switched from groups I-III and VI to groups I, IV, V, and VIII around 2013. H3 AIVs in groups I and V were maintained in poultry until at least 2016, which likely accompanied their dissemination from the northern to the southern regions of Vietnam. Groups VI-VIII AIVs were antigenically distinct from the other groups. Some H3 AIV isolates had similar N6 neuraminidase and matrix genes as H5 highly pathogenic avian influenza viruses (HPAIVs). These results reveal that genetically and antigenically different H3 AIVs have been co-circulating in poultry in Vietnam. Poultry is usually reared outside in this country and is at risk of infection with wild waterbird-originating AIVs. In poultry flocks, the intruded H3 AIVs must have experienced antigenic drift/shift and genetic reassortment, which could contribute to the emergence of H5 HPAIVs with novel gene constellations.
迄今为止，禽流感病毒（AIVs）一直存在于东亚国家活禽市场的家禽中。自2011年以来，我们一直在越南的家禽群体中进行病毒监测，目标是控制禽流感。在整个这项研究中，从市场和鸭场的2760份家禽拭子样本中分离出110株H3禽流感病毒。分离株的H3血凝素（HA）基因在系统发育上分为八组（I - VIII）。在其他七个基因片段中也观察到了遗传多样性。I - IV组还包括来自野生水鸟的禽流感病毒。家禽中的流行毒株在2013年左右从I - III组和VI组转变为I、IV、V和VIII组。I组和V组的H3禽流感病毒在家禽中至少维持到2016年，这可能伴随着它们从越南北部传播到南部地区。VI - VIII组禽流感病毒在抗原性上与其他组不同。一些H3禽流感病毒分离株具有与H5高致病性禽流感病毒（HPAIVs）相似的N6神经氨酸酶和基质基因。这些结果表明，遗传和抗原性不同的H3禽流感病毒一直在越南的家禽中共存。在这个国家，家禽通常在户外饲养，有感染源自野生水鸟的禽流感病毒的风险。在家禽群体中，侵入的H3禽流感病毒必定经历了抗原漂移/转变和基因重配，这可能有助于出现具有新型基因组合的H5高致病性禽流感病毒。
