请教OG11 -8的阅读题

phoebe2009

Although genetic mutations in bacteria and viruses can lead to epidemics, some epidemics are caused by bacteria and viruses that have undergone no significant genetic change. In analyzing the latter, scientists have discovered the importance of social and ecological factors to epidemics. Poliomyelitis (poliomyelitis: n.小儿麻痹症, 急性骨髓灰白质炎), for example, emerged as an epidemic in the United States in the twentieth century; by then (by then: 到那时候), modern sanitation was able to delay exposure to polio (POLIOMYELITIS)
            until adolescence or adulthood, at which time polio infection produced paralysis. Previously, infection had occurred during infancy, when it typically provided lifelong immunity without paralysis. Thus, the hygiene that helped prevent typhoid epidemics indirectly fostered a paralytic polio epidemic. Another example is Lyme disease, which is caused by bacteria that are transmitted by deer ticks. It occurred only sporadically during the late nineteenth century
            but has recently become prevalent in parts of the United States, largely due to an increase in the deer population that occurred simultaneously with the growth of the suburbs and increased outdoor recreational activities in the deer’s habitat. Similarly, an outbreak of dengue hemorrhagic fever became an epidemic in Asia
            in the 1950’s because of ecological changes that caused Aedes aegypti, the mosquito that transmits the dengue virus, to proliferate. The stage is now set in the United States for a dengue epidemic because of the inadvertent introduction and wide dissemination of another mosquito, Aedes
                    albopictus.

121.
                            It can be inferred from the passage that Lyme disease has become prevalent in parts of the United States because of which of the following?

(A) The inadvertent introduction of Lyme disease bacteria to the United States

(B) The inability of modern sanitation methods to eradicate Lyme disease bacteria

(C) A genetic mutation in Lyme disease bacteria that makes them more virulent

(D) The spread of Lyme disease bacteria from infected humans to noninfected humans（E）

(E) An increase in the number of humans who encounter deer ticks

·      The best answer is E. The passage mentions two reasons for the rise in the prevalence of Lyme disease: an increase in the number of deer and thus of the number of the deer ticks that carry the bacteria, and the proliferation of human activity in the deer’s habitat, suggesting that contact between humans and deer ticks has increased significantly since the late nineteenth century.
                            

·      No mention is made of the transmission of Lyme disease bacteria to the United States, or of any genetic mutations in the bacteria, so A and C can be eliminated. 无

·      Choice B is incorrect because the passage does not suggest that any attempt was made to eradicate Lyme disease through better sanitation. 无

·      Choice D is incorrect because the passage describes only deer ticks as a source of Lyme disease bacterium, not infected humans. 不相关

问题是:

为什么D不对,如果没有人与人之间的传递,疾病怎么会流行,而且这题问的是It  can be inferred from the passage....这个也是能推出来的啊...

谢谢.

rpch2004

这是og11的题吗？我怎么找不到？

[此贴子已经被作者于2008-10-15 0:24:38编辑过]

amom

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amom

When people hiking outside, they probably meet deer.Provide if human feed the lovely deer, the deer will tick(tian3) his hand palm which may transmit Lyme disease(as E said), the nest step will be D: transmit Lyme from infected human to noninfected human.

I had tried to feed two wild deers just outside my house before. It is a fantasitc experience! Wild animals are protected so well in USA that they are just be friends with humans.

phoebe2009

以下是引用amom在2008-10-15 3:54:00的发言：
When people hiking outside, they probably meet deer.Provide if human feed the lovely deer, the deer will tick(tian3) his hand palm which may transmit Lyme disease(as E said), the nest step will be D: transmit Lyme from infected human to noninfected human.

I had tried to feed two wild deers just outside my house before. It is a fantasitc experience! Wild animals are protected so well in USA that they are just be friends with humans.

偶也在想这两步都是可能的,所以偶对答案不确定.