什么是猪流感？What is Swine Influenza?
猪流感(Swine Influenza, swine flu)是猪的一种呼吸道疾病，它的病原是一种能造成周期性爆发的A型流感病毒。猪流感病毒的致病率很高，但猪的死亡率低。猪流感病毒在全年都有可能传播，但大部分会在深秋和冬季月份爆发，这一点与人流感类似。典型的猪流感病毒(A型H1N1病毒)于1930年第一次从猪身上分离出来. Swine Influenza (swine flu) is a respiratory disease of pigs caused by type A influenza virus that regularly causes outbreaks of influenza in pigs. Swine flu viruses cause high levels of illness and low death rates in pigs. Swine influenza viruses may circulate among swine throughout the year, but most outbreaks occur during the late fall and winter months similar to outbreaks in humans. The classical swine flu virus (an influenza type A H1N1 virus) was first isolated from a pig in 1930.
现在有多少种猪流感病毒？How many swine flu viruses are there?
就像所有的流感病毒一样，猪流感病毒也在不停地变化当中。禽流感，人流感以及猪流感病毒都会对猪造成感染；当不同种来源的流感病毒同时感染时，病毒之间就会重新“洗牌”(交换基因)，从而产生一种新的“禽人猪”混合病毒。随着时间的推移，也出现了猪流感病毒的多种变种：现在人们从猪身上分离出了4种主要的A型流感病毒亚型： H1N1, H1N2, H3N2, H3N1。但最近从猪分离出来的流感病毒大部分都是H1N1型病毒。 Like all influenza viruses, swine flu viruses change constantly. Pigs can be infected by avian influenza and human influenza viruses as well as swine influenza viruses. When influenza viruses from different species infect pigs, the viruses can reassort (i.e. swap genes) and new viruses that are a mix of swine, human and/or avian influenza viruses can emerge. Over the years, different variations of swine flu viruses have emerged. At this time, there are four main influenza type A virus subtypes that have been isolated in pigs: H1N1, H1N2, H3N2, and H3N1. However, most of the recently isolated influenza viruses from pigs have been H1N1 viruses.
人类会感染猪流感吗？Can humans catch swine flu?
Swine flu viruses do not normally infect humans. However, sporadic human infections with swine flu have occurred. Most commonly, these cases occur in persons with direct exposure to pigs (e.g. children near pigs at a fair or workers in the swine industry). In addition, there have been documented cases of one person spreading swine flu to others. For example, an outbreak of apparent swine flu infection in pigs in Wisconsin in 1988 resulted in multiple human infections, and, although no community outbreak resulted, there was antibody evidence of virus transmission from the patient to health care workers who had close contact with the patient.
人类感染猪流感的症状是什么？What are the symptoms of swine flu in humans?
The symptoms of swine flu in people are expected to be similar to the symptoms of regular human seasonal influenza and include fever, lethargy, lack of appetite and coughing. Some people with swine flu also have reported runny nose, sore throat, nausea, vomiting and diarrhea.
吃猪肉会感染猪流感吗？Can people catch swine flu from eating pork?
No. Swine influenza viruses are not transmitted by food. You can not get swine influenza from eating pork or pork products. Eating properly handled and cooked pork and pork products is safe. Cooking pork to an internal temperature of 160°F kills the swine flu virus as it does other bacteria and viruses.
猪流感是如何传播的？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.
如何诊断人感染了猪流感？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.
感染了猪流感的病人有何治疗措施？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.