Drugs are one of the (61)________ profession’s most valuable tools. Doctors prescribe drugs to (62)_______or prevent many diseases. Every year, penicillin and other (63)________ drugs save the lives of countless victims of pneumonia and other dangerous infectious diseases. Vaccines prevent attacks by such diseases as(64)________, polio, and smallpox. The use of these and many other drugs (65)________ helped millions of people live longer, healthier lives than would (66)________ have been possible.Almost all our most important drugs, however, were unknown before the 1900’s. For example, the sulfa drugs and antibiotics did not come into use (67)________ the late 1930’s and early 1940’s. Before that time, about 25 percent of all pneumonia victims in the United States died of the disease. The new drugs quickly reduced the (68)________ rate from pneumonia to less than 5 percent. Polio vaccine was introduced in 1955. At that time, polio struck about 30,000 to 50,000 Americans each year. (69)________ 1960, the use of the vaccine has reduced the number of new polio cases to about 3,000 a year. In 1900, most Americans did not live (70)________ the age of 47. Today, Americans live an average of more than 70 years, in great part because of the use of modern drugs.
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