第五篇Tracking Down HIV
In the summer of 1980, a patient had a strange purplish spot removed from below his ear. It was Kaposi’s sarcoma, a rare form of skin cancer. This patient also had lymph node swelling and exhaustion. In November 1980, a Los Angeles immunologist examined a young man who had diseases linked to immune system malfunctions. The doctor had a T-cell count taken of the patient’s blood. T-cells are a type of white blood cell that plays a key role1 in immune responses. The patient had no helper
T-cells.
By the end of 1980, 55 Americans were diagnosed with infections related to immune system breakdown; four had died. A year later the death toll was 74. Intravenous drug users had T-cell abnormalities. People who had received blood transfusions showed symptoms of immune system breakdown. By July 1982, 471 cases of the disease, now called Acquired Immune Deficiency Syndrome (AIDS), had been reported; 184 people had died.
In April 1984, American virologist Dr. Robert Gallo isolated the pathogen, or disease producer, responsible for2 AIDS. He called it HTLV-III. In Paris, Dr. Luc Montagnier identified a virus he called LAV. An international panel of scientists determined that both men had found the same virus. It became known as Human Immunodeficiency virus (HIV). Blood banks began screening for HTV in 1985, but by then about 29,000 people had been infected through blood transfusions. Some 12,000 hemophiliacs had contracted HIV through blood-clotting products. By 1995, 477,900 Americans had AIDS; 295,500 had died.
In 1996, researchers announced drugs that reduced HIV in infected people. Today scientists are testing vaccines and believe that if HIV can be suppressed, then perhaps it can be eradicated3, but it is still a race against time.
词汇：
spot n. 地点，斑点，斑块，青春痘
lymph n. 淋巴结
sarcoma n. 肿瘤，肉瘤，恶性毒瘤
exhaustion n. 衰竭，耗尽，精疲力竭
immunologist n.免疫学家
malfunction n. 故障，失灵，疾病
count n. 计数，计算
infection n. 传染病，感染
breakdown n. 故障，衰弱，崩溃
toll n. 代价，死亡人数
intravenous drug n. 静脉注射药物
abnormalities n. (abnormality的复数形式)畸形，异常情况
blood transfusion n. 输血
symptom n.症状
virologist n. 病毒学家
virus n. 病毒
panel n.座谈小组，仪表板
hemophiliac n. 血友病患者
vaccine n. 疫苗
注释：
1．play a key role...扮演一个关键角色，有至关重要的作用
2．be responsible for...对……负责，是……的原因
3．can be eradicated可以被根除的
练习：
1．This passage is mainly about ____.
A the spreading of the disease known as HIV
B the work of Dr. Robert Gallo
C infectious diseases
D the symptoms of HIV
2．A T-cell is a ____.
A patient’s blood
B deadly strain of tuberculosis
C white blood cell important in providing immunity to disease
D red blood cell
3．The final paragraph leads the reader to see that scientists ____.
A have no hope in ever finding a cure for HIV
B have hope that a cure for HIV will be found
