Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Brescia, Italy.
Zoonoses Public Health. 2011 Dec;58(8):573-81. doi: 10.1111/j.1863-2378.2011.01406.x. Epub 2011 Apr 11.
In April 2009, a novel H1N1 influenza A virus (pH1N1) was recognized as the cause of the flu pandemic in humans. Here, we report the isolation of pH1N1 virus from the lung homogenates of two cats, which died after severe respiratory symptoms. The cats belonged to a cat colony consisting of 90 caged cats and were found dead following a 2-week period of respiratory and gastrointestinal diseases in the colony. During the outbreak, 25 cats died and 50% of the animal colony showed anorexia, depression, respiratory and gastrointestinal symptoms. Histological examination of the lungs of the two tested cats displayed lesions centred on terminal airways with epithelial bronchiolar hyperplasia and alveolar necrosis. Influenza A virus was detected in the lung tissues by immunohistochemistry and real-time RT-PCR (rRT-PCR). Partial sequences of haemagglutinin (HA) genes and complete sequences of neuraminidase (NA) genes of the two isolates displayed high similarity to the pH1N1 viruses circulating in humans (99% for HA gene and 100% for NA gene). To determine whether the pandemic virus had circulated among cats, serum samples and pharyngeal swabs were collected from 38 cats of the colony. Serum samples were tested by ELISA to detect antibodies against pH1N1 nucleoprotein and by hemagglutination-inhibition test, while pharyngeal swabs were examined by pH1N1 specific rRT-PCR. Twenty-one (55%) of the tested cats carried antibodies against the isolated strain and two swabs were positive for the presence of pH1N1 RNA. Our results confirm that the pH1N1 virus was able to infect cats and raise the hypothesis of the circulation of the virus within the colony being due to cat-to-cat transmission. The case reported here provides, to the best of the authors' knowledge, the first description of the pH1N1 infection involving numerous cats that lived in a restricted area with limited contact with humans.
2009 年 4 月，一种新型 H1N1 甲型流感病毒（pH1N1）被确认为人类流感大流行的病原体。在此，我们报告了从两只死于严重呼吸道症状的猫的肺匀浆中分离出 pH1N1 病毒。这两只猫属于一个由 90 只笼养猫组成的猫群，在该猫群出现呼吸道和胃肠道疾病 2 周后死亡。在疫情爆发期间，有 25 只猫死亡，该动物群中有 50%的猫出现厌食、抑郁、呼吸和胃肠道症状。对两只检测猫的肺组织进行组织学检查显示，病变集中在终末气道，表现为上皮性细支气管增生和肺泡坏死。免疫组织化学和实时 RT-PCR（rRT-PCR）检测到肺组织中存在甲型流感病毒。两株分离株的血凝素（HA）基因部分序列和神经氨酸酶（NA）基因全长序列与人流行的 pH1N1 病毒高度相似（HA 基因 99%，NA 基因 100%）。为了确定大流行病毒是否在猫群中传播，从该猫群的 38 只猫中采集血清样本和咽拭子。通过 ELISA 检测血清样本中针对 pH1N1 核蛋白的抗体，通过血凝抑制试验检测，同时通过 pH1N1 特异性 rRT-PCR 检测咽拭子。在检测的 38 只猫中，有 21 只（55%）携带针对分离株的抗体，有 2 个咽拭子对 pH1N1 RNA 呈阳性。我们的研究结果证实 pH1N1 病毒能够感染猫，并提出了病毒在猫群中传播的假设，这可能是由于猫与猫之间的传播所致。本报告所描述的病例是首例已知的涉及在有限接触人类的限制区域生活的大量猫感染 pH1N1 的病例。
