Đang chuẩn bị nút TẢI XUỐNG, xin hãy chờ
Tải xuống
Illness with influenza in pigs was first recognized during the influenza pandemic of 1918 to 1919, and a swine influenza virus was first isolated from a human in 1974 [46]. In 1976, swine influenza virus caused a respiratory illness with one fatality among 13 soldiers in Fort Dix, New Jersey [7]. No exposure to pigs was found. A subsequent epidemiologic study showed that up to 230 soldiers had been infected with the virus. | .