We report a disease and mortality event involving swans, seals, and a fox at a wildlife rehabilitation center in the United Kingdom during late 2020. Five swans had onset of highly pathogenic avian influenza virus infection while in captivity. Subsequently, 3 seals and a fox died (or were euthanized) after onset of clinical disease. Avian-origin influenza A virus subtype H5N8 was retrospectively determined as the cause of disease. Infection in the seals manifested as seizures, and immunohistochemical and molecular testing on postmortem samples detected a neurologic distribution of viral products. The fox died overnight after sudden onset of inappetence, and postmortem tissues revealed neurologic and respiratory distribution of viral products. Live virus was isolated from the swans, seals, and the fox, and a single genetic change was detected as a potential adaptive mutation in the mammalian-derived viral sequences. No human influenza-like illness was reported in the weeks after the event.

我们报告了 2020 年底在英国一家野生动物康复中心发生的涉及天鹅、海豹和一只狐狸的疾病和死亡事件。五只天鹅在圈养期间感染了高致病性禽流感病毒。随后，3 只海豹和一只狐狸在临床疾病发作后死亡（或被安乐死）。禽源甲型流感病毒亚型 H5N8 被回顾性确定为疾病的病因。海豹中的感染表现为癫痫发作，对死后样本进行的免疫组织化学和分子检测检测到病毒产物的神经系统分布。这只狐狸在突然出现食欲不振后一夜之间死亡，尸检组织显示病毒产物在神经系统和呼吸系统中分布。从天鹅、海豹和狐狸身上分离出活病毒，并且检测到单个遗传变化是哺乳动物衍生病毒序列中的潜在适应性突变。事件发生后的几周内没有报告人类流感样疾病。