Influenza Unit, Division of Transboundary Animal Diseases, National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), Kannondai, Tsukuba, Ibaraki, Japan.
Transbound Emerg Dis. 2019 May;66(3):1227-1251. doi: 10.1111/tbed.13141. Epub 2019 Feb 27.
In Japan during the 2016-2017 winter season, clade 2.3.4.4 highly pathogenic avian influenza viruses (HPAIVs) of the H5N6 subtype caused 12 outbreaks in chicken and Muscovy duck farms. These viruses have been circulating in Vietnam and China since 2014. In this study, we evaluated the susceptibility of chicken, Pekin duck (Anas platyrhynchos domesticus) and Muscovy duck (Cairina moschata) to H5N6 HPAIVs that originated in Japan, Vietnam and China. The H5N6 HPAIVs examined in this study were highly lethal to chickens compared with their pathogenicity in Pekin duck and Muscovy duck. One of five chickens infected with A/Muscovy duck/Aomori/1-3T/2016 (MusDk/Aomori) survived despite viral shedding, although all of the chickens infected with the other viruses died. The 50% chicken lethal dose differed among the Japanese strains that shared the same gene constellation indicating that gene constellation was not a major determinant of pathogenicity in chicken. MusDk/Aomori, A/chicken/Niigata/1-1T/2016 (Ck/Niigata) and A/duck/Hyogo/1/2016 (Dk/Hyogo) infected all Muscovy ducks inoculated; Ck/Niigata killed 50% of the ducks it infected whereas the other two did not kill any ducks. A/chicken/Japan/AnimalQuarantine-HE144/2016 (HE144) isolated from chicken meat that originated in China was highly pathogenic to Pekin duck: all of the ducks died within 3.75 days of inoculation. This study shows that the pathogenicity of the clade 2.3.4.4 H5N6 HPAIVs differs not only between hosts but also within the same host species.
在 2016-2017 年日本冬季，H5N6 亚型 2.3.4.4 分支高致病性禽流感病毒（HPAIV）在鸡和麝香鸭养殖场引发了 12 次疫情。自 2014 年以来，这些病毒一直在越南和中国传播。在这项研究中，我们评估了源自日本、越南和中国的 H5N6 HPAIV 对鸡、北京鸭（Anas platyrhynchos domesticus）和麝香鸭（Cairina moschata）的易感性。与它们在北京鸭和麝香鸭中的致病性相比，本研究中检测到的 H5N6 HPAIV 对鸡具有高度致死性。尽管有病毒排出，但感染 A/Muscovy duck/Aomori/1-3T/2016（MusDk/Aomori）的五只鸡中有一只存活下来，尽管感染其他病毒的所有鸡都死亡了。具有相同基因组合的日本株之间的 50%鸡致死剂量不同，这表明基因组合不是鸡致病性的主要决定因素。感染 A/chicken/Niigata/1-1T/2016（Ck/Niigata）和 A/duck/Hyogo/1/2016（Dk/Hyogo）的所有麝香鸭都被 MusDk/Aomori 感染；Ck/Niigata 杀死了感染它的 50%的鸭子，而其他两种则没有杀死任何鸭子。从中国起源的鸡肉中分离出的 A/chicken/Japan/AnimalQuarantine-HE144/2016（HE144）对北京鸭具有高度致病性：所有鸭子在接种后 3.75 天内死亡。本研究表明，2.3.4.4 分支 H5N6 HPAIV 的致病性不仅在宿主之间不同，而且在同一宿主物种内也不同。
