考研英語聽力基本功訓(xùn)練1: Passage22

AIDS represents a different type of challenge to business firms when dealing with consequences of this terrible diseas

AIDS is a fatal disease that breaks down the body's ability to defend itself against illness and infectio

AIDS is especially dangerous because a long time(typically five years) elapses between someone's first exposure to the AIDS viru

and actual development of the diseas

During this period,people may not show any symptoms of AID

and they probably don't even know they have i

but they are still carriers who can give the disease to other

This large pool of unknown carriers accounts for the rapid spread of the diseas

In 1982,only 1 013 cases of AIDS were reported;today the victims number over 200 000.