Dowdle W R, Hattwick M A
J Infect Dis. 1977 Dec;136 Suppl:S386-9. doi: 10.1093/infdis/136.supplement_3.s386.
Influenza in swine was first recognized as an epizootic disease in 1918. During that same year influenza virus in humans caused the worst pandemic on record. The virus of swine influenza was isolated in 1930. Swine influenza virus was first isolated from humans in 1974. Since then, including the cases at Fort Dix, there have been a total of nine viral isolations from humans in the United States. Serologic evidence of infections with swine influenza virus in humans has also been obtained. Evidence for transmission of swine influenza virus to humans before 1974 is minimal and circumstantial. Recent recognition of infections with swine influenza virus may be the result of better surveillance, increased numbers of susceptible humans, or increased viral infectivity for humans. Nevertheless, the apparent frequency of human infections and the declining levels of antibodies to swine influenza virus in the human population suggest that influenza viruses of swine may be a potential sources of epidemic disease for humans.
猪流感于1918年首次被确认为一种 epizootic 疾病。同年，人类流感病毒引发了有记录以来最严重的大流行。猪流感病毒于1930年被分离出来。1974年首次从人类身上分离出猪流感病毒。从那时起，包括迪克斯堡的病例在内，美国总共从人类身上进行了9次病毒分离。也获得了人类感染猪流感病毒的血清学证据。1974年之前猪流感病毒传播给人类的证据很少且具有偶然性。最近对猪流感病毒感染的认识可能是由于监测改善、易感人群数量增加或病毒对人类的传染性增强。然而，人类感染的明显频率以及人群中针对猪流感病毒抗体水平的下降表明，猪流感病毒可能是人类流行病的潜在来源。
