SARS-CoV-2冠狀病毒會感染貓
冠狀病毒是具有二十面體對稱性的包膜病毒,直徑約為 80-220 nm,由不分段的單鏈正鏈 RNA 基因組組成,屬於Nidovirales中的冠狀病毒科,可感染多種哺乳動物和鳥類,引起呼吸道和腸道疾病。2019年12月,中國湖北省會武漢市首次發現了導致肺炎和死亡的重症病例。不久之後,病例數量急劇飆升,蔓延到中國和世界各地。該疾病的病原體已被確認為一種新型冠狀病毒/嚴重急性呼吸系統綜合症冠狀病毒2型 (Severe acute respiratory syndrome coronavirus 2, SARS-CoV-2, COVID 19)。貓隻因為具有與人類高同源性的受體,對SARS-CoV-2具有高感受性(de Morais et al., 2020)。第一隻SARS-CoV-2陽性貓是在比利時被診斷出,而該貓的主人也在義大利北部旅行後檢測出SAR-CoV-2,這隻貓表現出呼吸道症狀、噁心和腹瀉。治療期間,這隻貓的嘔吐物和糞便中反覆出現大量SARS-CoV-2病毒抗原(McNamara, Richt, and Glickman, 2020)。後續研究表明,貓非常容易受到亞臨床感染 (subclinical infection),會有長期口腔和鼻腔的病毒脫落 (virus shedding),並且能夠直接接觸傳播給其他貓,且會產生強大的中和抗體反應,以防止第二次的病毒攻擊並預防再次感染(Bosco-Lauth et al., 2020; Halfmann et al., 2020)。香港在2020年2月11日至8月11日期間對50隻貓進行了採樣,這些貓都來自SARS-CoV-2的家庭或其他密切接觸者,發現了6例健康的貓涉及明顯的人感染貓的案例(Barrs et al., 2020)。在台灣2022-2025年貓隻初步的血清學調查研究發現,於隨機共695貓隻的血清樣本中,陽性率高達31.94% (Goh et al., 2026, unpublished data)。
參考文獻:
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