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解析:Coming Soon: the Next Great FluEp

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Coming Soon: the Next Great FluEpidemic
The virus first came to officials’ attention in a bag of dead chickens.Early in March 1997, a farmer from Hong Kong’s New Territories carried them into theAgriculture and FisheriesDepartment laboratory. The final state of some birds was a hideous, bloody mush.Cultures of their organs revealed they had died of avian influenza, type H5N1. Influenza of the H5 subtype had never been known to infect humans.But in the next seven months, 18 Hong Kong residents fell ill with H5N1 and six dieD、
In lateDecember 1997, public health officials took a drastic step, ordering the slaughter of every chicken in every farm and marketplace in Hong Kong. The HSN1 virus seemed to disappear but for how long
The specter of the 1918 flu was raised by this new avian flu. The 1918 flu was one of the most changeable and resistant viruses known to man.After we’ve been infected with one strain, it can mutate and infect us again. We are only immune to flu strains our bodies have seen before.
A、flu can also "jump species" to an animal it has never infected before, once such a flu moves into humans, if it can "learn" to pass easily between them, it can spark a pandemic—a global outbreak.
Birds carry the flu virus in their intestines and excrete it in their feces. In all likelihood, shoppers who got sick with H5 touched surfaces contaminated with chicken feces. Humans, however, carry flu in their respiratory tracts and usually spread them in a cough or sneeze. Flu strains that travel this way are highly contagious.
The H5 virus in Hong Kong was different. It sickened very few, but killed a third of those infecteD、Most who got sick with H5 seemed to catch it directly from a bird they bought in a live-poultry market.
After the Hong Kong outbreak, flu experts feared that H5—already deadly to humans—might learn to move between humans as well as between birds. That "raises the specter of 1918", says NancyCox, chief of the InfluenzaBranch of the U. S.Centers forDiseaseControl and PreventionCDCP).
Geographic isolation was no protection during the 1918 pandemiC、In theAlaska Territory, the mortality rate in some villages was as high as 90 percent.All told, at least 500000Americans perisheD、It could happen again.
The virus that became the Spanish flu probably came from a birD、Avian-flu expertDr. Robert Webster of St. JudeChildren’s Research Hospital in Memphis, Tenn., believes the virus may have leapt straight from birds to humans, possibly a year to two before the pandemic began. Once lodged in human lungs, it quickly passed from person to person in a simple cough or sneeze. To avoid that grim possibility, here are three measures all nations need to take:
The first step is better surveillance. Most countries, though, don’t start tracking avian flu until after an epidemic kills their chickens. The United States dramatically increased its monitoring after a deadly outbreak in Pennsylvania in the early 1980s. The USDA、(United StatesDepartment ofAgriculture) provides diagnostic support. Some virologists recommend enhancing surveillance of swine flu too. The U. S. National Institutes of Health is beginning to study the issue.
Elsewhere, the coverage is not good enough, saysDr. W. Paul Glezen of theBaylorCollege of Medicine’s Influenza ResearchCenter. He namesAfrica and SouthAmerica as areas where the World Health Organizations net is incomplete.
Another important measure is producing more vaccines and flu shots. Only three of the 15 known influenza subtypes—H1, H2 and H3—have been found in people. Vaccines exist for each, and an H5 vaccine is now being developeD、Some experts believe that we should develop a vaccine for the other known subtypes as well.
Health authorities add that more people need flu shots now. We should manufacture 120 million doses a year
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[解析] 本题为篇章插话题,考查考生将特定的一句话根据与它顺序相连的四个句子之间的逻辑关系插入其中一个方框的能力。要做好此题,考生必须深入理解各句子间的词汇、语法和连接的逻辑关系。该自然段的第一句谈到:“In March of this year, Hong Kong’s Agriculture and Fisheries Department announced it had found H5N1 in the goose excrement of a poultry stall (香港农业渔业部于今年3月宣布他们在一家家禽饲养棚的鹅粪中发现了H5N1)”。接着在第一个方框后面谈到这种病毒和1997年的病毒并不相同。由此可以判断出句子“H5 was back”应放在A处,因为“The virus was not identical...”中的the virus与插入句的H5指的是同一事物,插入句在此处起承上启下的作用。 document.getElementById("warp").style.display="none"; document.getElementById("content").style.display="block"; 查看试题解析出处>>

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