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  3. HIV is a viral infection that causes a chronic life-threatening condition acquired immune deficiency syndrome(AIDS). AIDS occurs

HIV is a viral infection that causes a chronic life-threatening condition acquired immune deficiency syndrome(AIDS). AIDS occurs

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问题     HIV is a viral infection that causes a chronic life-threatening condition acquired immune deficiency syndrome(AIDS). AIDS occurs when the HIV infection damages or destroys the cells of the immune system, reducing the body’s ability to fight off bacterial, viral and fungal infections.
    HIV is caused by a virus called the human immunodeficiency virus. It’s most commonly spread among adults by sexual contact with an infected partner.
【C1】______
    HIV was first reported in the early 1980s. Since then, it has spread worldwide. There are now an estimated 40 million people living with HIV, including about 2. 5 million children under 15.
【C2】______
    The initial infection with HIV may cause a brief flu-like illness two to six weeks after infection, with symptoms such as fever, headache, sore throat and swollen lymph glands(淋巴腺). However, many people don’t notice any particular symptoms and children are often infected while in the womb.
【C3】______
    There appear to be two general patterns of illness in HIV-infected children. About 20 percent develop serious disease in the first year of life and most of these children die by the age of four. In the remaining 80 percent, the disease progresses more slowly.
【C4】______
    Other symptoms may include weight loss, diarrhea, fever, cough, weakness, shortness of breath, headaches and even development of a variety of cancers. If untreated, these problems and related complications may be rapidly fatal.
    HIV is usually diagnosed using a blood test that detects antibodies to the virus. It may take up to 12 weeks after infection for these antibodies to be made, so an HIV test may initially be negative.
【C5】______
    Newer blood tests can detect tiny quantities of the virus in the infant’s blood, giving an accurate diagnosis in about 95 percent of HIV-infected infants by three months of age.
    Drug treatments, using a combination of several drugs known as highly active antiretroviral therapy, have greatly improved the outlook in AIDS. But drugs can’t cure the infection and side effects and drug resistance are still a major problem. Scientists are doing research to find more therapies that can best improve patients’ quality of life.
[A]It can also spread through infected blood and contaminated needles or syringes(for example in drug abuse or medical treatments). In the majority of cases of children with HIV, the virus has been transmitted from the mother during pregnancy, delivery or through breastmilk.
[B]Sub-Saharan Africa has been most severely affected by HIV/AIDS and many millions have died, but the AIDS epidemic is also growing fast in some Asian and European countries.
[C]World AIDS Day is commemorated around the globe on December 1st. It celebrates progress made in the battle against the epidemic—and brings into focus remaining challenges.
[D]AIDS cannot yet be cured, although there is increasing success in controlling the infection, using a combination of drugs. Many, but not all, infected people in some developed countries can now expect to live a long and active life. Sadly, in some developing countries, there are often no funds for drugs—and the prognosis is far gloomier.
[E]However, all children born to infected mothers receive some of their mother’s antibodies to HIV. These may persist for up to 18 months, making antibody tests inaccurate.
[F]There follows a period in which people feel well and may not even be aware that the virus is multiplying inside them and damaging their immune system. After a time(sometimes many years)symptoms return.
[G]An HIV-positive child often fails to gain weight and doesn’t grow properly. They may develop problems with walking, or show delayed mental development. They may also develop cerebral palsy.
【C5】
选项
答案E
解析 上文已经提到HIV抗体的形成耗时数月，此处补充说明一种特殊情况。婴儿可能从母亲那里直接遗传抗体，并在体内潜伏长达18个月，使得抗体测试失准。另外从下文首句中的newer blood tests，也可推断出这里应该讲传统的检测方法。
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