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Transcript
LESSON 122
1
introduction specializes fright centuries
2
Semmelweis Pasteur Jenner fever
division infection garbage childhood
convinced pasteurization smallpox
improvements typhoid affects
diphtheria organisms poisoning purify
3
1. bacteria
2. vaccination
3. substance
4. explanation
5. life expectancy
4
Contributions of Jenner, Pasteur, and Semmelweis
Let's skip ahead in time to about 1850. During the 350 years since 1500, a number of
improvements had come about in medicine; however, conditions were still very
different from what we know today. The average life expectancy of people born in
the cities was now about thirty-seven years. If people survived childhood, they
could expect to live far beyond their thirty-seventh birthday; however, chances of
living through childhood were not too good.
Diseases like smallpox, typhoid fever, and diphtheria still took the lives of thousands of
children every year. Another killer was blood poisoning. Blood poisoning is * a
serious infection that affects a person's whole system. A fever starts, and if the
infection continues to develop, the person dies. The doctors of 1850 did not
understand that blood poisoning is caused by tiny organisms called bacteria.1
An Englishman named Edward Jenner had introduced a method for preventing
smallpox about fifty years earlier. The method was called vaccination. Even by
1850 some people were not convinced that vaccination worked. They feared being
stuck with a needle and having some strange substance injected into their body.
Even some doctors were slow to accept vaccination.2
During the twenty-five-year * period following Jenner's introduction of vaccination,
about six million people in Europe died of smallpox. The toll was especially great
in the United States, particularly among the American Indians, who had no
resistance to the disease. Entire villages of Native Americans died from smallpox.
In fact, one hundred years after Jenner introduced vaccination, there was a severe
outbreak of smallpox in the town where Jenner had lived and worked.3
One of the greatest of all medical scientists was Louis Pasteur. He discovered that
diseases were spread by bacteria. He demonstrated that bacteria were living things
and were born, like all * other life-forms. Until his theories were
accepted, many doctors believed that flies and other small life-forms simply grew out of
garbage or dirt. They didn't believe that these animals were born from a parent, like
larger life-forms. Most of these doctors did not even believe that bacteria existed
because they were invisible to the naked eye.4
Pasteur showed how to control the spread of disease. He demonstrated that harmful
bacteria in milk could be killed by applying heat. This method, called
pasteurization, assured a safe milk supply. his other great lifesaving contribution
resulted from his work * in the area of vaccination. He discovered that harmful
bacteria (germs) cause some diseases by multiplying in the human body. He
discovered how to stop this process by vaccinating a person with a weakened form
of the germs. It is impossible to estimate the number of lives saved by Pasteur's
work.5
A doctor named Semmelweis lived in Europe around 1850. He wasn't familiar with the
work of Pasteur. But he showed that some problems of controlling bacteria could
be solved by using common sense.
Semmelweis was in charge of a large hospital that specialized in caring for women who
were * having babies. The women went into the hospital to have their babies, and a
few days after the baby was born the mother and the baby went homeā€”if the
mother was still alive.
There were two divisions in the hospital. Semmelweis noticed a striking difference
between them. In one division, one of every ten women died after giving birth. In
the other, fewer than one of every thirty died.6
Semmelweis studied the figures and asked himself, "Why do more women die in
Division One than in Division Two?" Division One was staffed by doctors and
medical students. Division Two * was staffed by nurses. What was the difference
between the doctors and the nurses?
An explanation had been offered by some medical officials. It might be that some
women in Division One died of fright because
Division One had a bad reputation. Some women might have died of heart attacks
caused by fear.7