How does swine flu spread?

　　Influenza viruses can be directly transmitted from pigs to people and from people to pigs. Human infection with flu viruses from pigs are most likely to occur when people are in close proximity to infected pigs, such as in pig barns and livestock exhibits housing pigs at fairs. Human-to-human transmission of swine flu can also occur. This is thought to occur in the same way as seasonal flu occurs in people, which is mainly person-to-person transmission through coughing or sneezing of people infected with the influenza virus. People may become infected by touching something with flu viruses on it and then touching their mouth or nose.

　　猪流感是如何传播的？

　　流感病毒能够直接从猪传染到人，或者从人传染到猪。人被猪感染最常见的情形是人与受感染的猪有近距离接触，例如在猪圈里，或者在市场上展出的猪。人与人的猪流感传播也是可能的，它的传播方式被认为与季节性流感传播的方式一样，即主要通过病人的咳嗽，打喷嚏的方式在人群之间传播。在接触含有病毒的物体之后再摸嘴巴或者摸鼻子也有可能感染病毒。

　　What do we know about human-to-human spread of swine flu?

　　In September 1988, a previously healthy 32-year-old pregnant woman was hospitalized for pneumonia and died 8 days later. A swine H1N1 flu virus was detected. Four days before getting sick, the patient visited a county fair swine exhibition where there was widespreadinfluenza-like illness among the swine.

　　In follow-up studies, 76% of swine exhibitors tested had antibody evidence of swine flu infection but no serious illnesses were detected among this group. Additional studies suggest that one to three health care personnel who had contact with the patient developed mild influenza-like illnesses with antibody evidence of swine flu infection.

　　How can human infections with swine influenza be diagnosed?

　　To diagnose swine influenza A infection, a respiratory specimen would generally need to be collected within the first 4 to 5 days of illness (when an infected person is most likely to be shedding virus). However, some persons, especially children, may shed virus for 10 days or longer. Identification as a swine flu influenza A virus requires sending the specimen to CDC for laboratory testing.

　　What medications are available to treat swine flu infections in humans?

　　There are four different antiviral drugs that are licensed for use in the US for the treatment of influenza: amantadine, rimantadine, oseltamivir and zanamivir. While most swine influenza viruses have been susceptible to all four drugs, the most recent swine influenza viruses isolated from humans are resistant to amantadine and rimantadine. At this time, CDC recommends the use of oseltamivir or zanamivir for the treatment and/or prevention of infection with swine influenza viruses.

　　我们知道多少关于人与人之间的猪流感传播？

　　在1988年9月，一个之前健康的32岁孕妇因为肺炎住院并于8天后不幸死亡，从她身上检测出了H1N1猪流感病毒。病人在发病的4天前去了一个乡镇市场，那里的猪普遍感染上了类似于流感的疾病。

　　在随后的调查中，市场上76%的猪农被检出有抗体，证明他们被猪流感感染过，但没有发现这群人感染了严重的疾病。接着，研究发现大约有1-3名与患者接触的医护人员患上了轻微的类似流感的疾病，抗体检测证实他们是感染上了猪流感。

　　How common is swine flu infection in humans?

　　In the past, CDC received reports of approximately one human swine influenza virus infection every one to two years in the U.S., but from December 2005 through February 2009, 12 cases of human infection with swine influenza have been reported.

　　这种情况多吗？

　　在以往，CDC(Centers for Disease Control and Prevention，美国疾病预防与控制中心)在美国平均每1-2年会收到大约1起人感染猪流感的报告，但从2005年12月到2009年2月出现了12例猪流感感染人的病例。