Several influenza A viral subtypes were isolated from pigs during a severe outbreak of respiratory disease in Korea during 2005 and 2006.

在2005年和2006期间年韩国的猪爆发了严重的呼吸道疾病，并从中分离出了几种流感病毒A的亚型。

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Theory Background: Acute viral upper respiratory infection is a most common clinic infective disease, and about 70%-80% of it is caused by virus.

理论背景急性上呼吸道感染是临床最常见的一种感染性疾病，约有70% - 80%由病毒引起。

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Liver disease, the fifth biggest cause of death in England and Wales behind heart disease, cancer, stroke and respiratory disease, comes in more than 100 forms but is most commonly associated with alcohol abuse, obesity and viral hepatitis.

BBC: Liver damage is 'silent killer' cirrhosis patient warns