【正确答案】

【答案解析】[听力原文] 11-16
Professor
Hello, class. I guess you've all heard about swine flu these days. In fact, the World Health Organization says the swine flu outbreak is moving closer to becoming a pandemic. So, today I'll begin with the basics about swine influenza. Swine influenza (also swine flu) refers to influenza caused by any strain of the influenza virus endemic in pigs (swine). Strains endemic in swine are called swine influenza virus (SIV).
Of the three genera of human flu, two are endemic also in swine: Influenzavirus A is common and Influenzavirus C is rare. Influenzavirus B has not been reported in swine. Within Influenzavirus A and Influenzavirus C, the strains endemic to swine and humans are largely distinct.
Well, swine flu is common in swine and rare in humans. People who work with swine, especially people with intense exposures, are at risk of catching swine influenza if the swine carry a strain able to infect humans. However, these strains infrequently circulate between humans as SIV rarely mutates into a form able to pass easily from human to human. In humans, the symptoms of swine flu are similar to those of influenza and of influenza-like illness in general, namely chills, fever, sore throat, muscle pains, severe headache, coughing, weakness and general discomfort.
Diana
Excuse me, Professor, may I ask a question?
Professor
Yes, please, Diana.
Diana
As we know, the flu outbreak of this year started in Mexico. Then, why has it infected to humans?
Professor
A very good question. Well, the 2009 flu outbreak in humans is due to a new strain of influenza A virus subtype H1N1 that derives in part from human influenza, avian influenza, and two separate strains of swine influenza. The origins of this new strain are unknown, and the World Organization for Animal Health (OIE) reports that it has not been isolated in swine. It passes with apparent ease from human to human, an ability attributed to an as-yet unidentified mutation. The strain in most cases causes only mild symptoms and the infected person makes a full recovery without requiring medical attention and without the use of antiviral medicines.
Tom
Then, Professor, how should we prevent it?
Professor
Influenza spreads between humans through coughing or sneezing and people touching something with the virus on it and then touching their own nose or mouth. Swine flu cannot be spread by pork products, since the virus is not transmitted through food. The swine flu in humans is most contagious during the first five days of the illness although some people, most commonly children, can remain contagious for up to ten days. Diagnosis can be made by sending a specimen, collected during the first five days, to the CDC for analysis.
Recommendations to prevent spread of the virus among humans include using standard infection control against influenza. This includes frequent washing of hands with soap and water or with alcohol-based hand sanitizers, especially after being out in public. Although the current trivalent influenza vaccine is unlikely to provide protection against the new 2009 H1N1 strain, vaccines against the new strain are being developed and could be ready as early as June 2009.
Experts agree that hand-washing can help prevent viral infections, including ordinary influenza and the new swine flu virus. Influenza can spread in coughs or sneezes, but an increasing body of evidence shows little particles of virus can linger on tabletops, telephones and other surfaces and be transferred via the fingers to the mouth, nose or eyes. Alcohol-based gel or foam hand sanitizers work well to destroy viruses and bacteria. Anyone with flu-like symptoms such as a sudden fever, cough or muscle aches should stay away from work or public transportation and should see a doctor to be tested.
Social distancing is another tactic. It means staying away from other people who might be infected and can include avoiding large gatherings, spreading out a little at work, or perhaps staying home and lying low if an infection is spreading in a community.
[解析] 本题为主旨题，要求考生通过理解讲座中的关键词语、词组或事实来判断讲座的主旨大意。题目问的是：讲座是关于什么的?原文的第一段“So, today I'll begin with the basics about swine influenza”可知，讲座主要是介绍猪流感的基本信息和常识，所以答案是B。

【正确答案】/r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n /r/n

	Common	Rare	Not reported in swine
Influenzavirus A	√
Influenzavirus B			√
Influenzavirus C		√

【答案解析】[解析] 本题为细节题，考查考生是否听懂并记住讲座中提到的细节。题目要求考生将听到的细节对号入座。根据第二段的信息：“Influenzavirus A is common and Influenzavirus C is rare. Influenzavirus B has not been reported in swine”可知，答案应为表中所示。

【正确答案】

【答案解析】[解析] 本题为细节题，检验考生是否抓住第三段开头关于“哪些人容易得猪流感”的问题。根据教授的叙述：“People who work with swine, especially people with intense exposures, are at risk of catching swine influenza if the swine carry a strain able to infect humans”，答案应为A。

【正确答案】

【答案解析】[解析] 本题为细节多项题，为考查考生是否听懂讲座的细节而设置。题目问：猪流感的症状是什么?根据第三段的后半部分：“In humans, the symptoms of swine flu are similar to those of influenza and of influenza—like illness in general, namely chills, fever, sore throat, muscle pains, severe headache, coughing, weakness and general discomfort”得知答案是A、B、D。

【正确答案】

【答案解析】[解析] 本题为推论题，要求考生根据听力材料所陈述的事实做出结论和判断。题目问：老师说这段话是什么意思?根据：“Well, the 2009 flu outbreak in humans is due to a new strain of influenza A virus subtype H1N1 that derives in part from human influenza, avian influenza, and two separate strains of swine influenza”可判断，猪流感是一种由人流感、禽流感和两种猪流感称为H1N1的新病毒所引起的，因此选C为正确答案。

【正确答案】

【答案解析】[解析] 本题属于语用功能题，要求考生能够理解说话者讲一段话的目的。显然，教授在讲座的后面部分谈到了对于猪流感的预防问题：“This includes frequent washing of hands with soap and water or with alcohol-based hand sanitizers, especially after being out in public.”和“Social distancing is another tactic.”因此选择D。