The spread of disease can also be controlled through sanitation—
in other words, keeping our food, water, and environment clean.
Many diseases, including cholera and typhoid fever, which have
killed countless people throughout history, are spread through infect
ed drinking water. Other germs and parasites spread through
food that’s unclean, spoiled, or improperly cooked. Over the past
century, humans have learned a lot about preparing and storing
food safely and treating public water supplies, and the health
payoff has been extraordinary.
Surgery, dentistry, and medicine have also been made much safer,
thanks to the use of antiseptics (chemicals that kill germs).
Antiseptics are used to make a doctor’s tools sterile (germfree).
Before antiseptics became popular, many patients died from
infections that were spread on unclean surgical instruments. In
some cases, having surgery was actually more dangerous than
the disease itself.
Even the simple practice of washing one’s hands has made
an enormous difference in the overall health of the public, since
it keeps germs from spreading to everything—and everyone—a
person touches. Frequent hand washing has become a widespread
practice only within the past century or so. While it’s
especially important for health care workers and food preparers,
all people can benefit from washing their hands on a regular basis.
By the middle of the 19th century, surgeons had become fairly
skilled at their craft. However, even though the operations themselves
went well, half of the patients died in the days or weeks after surgery.
The cause was usually some kind of inflammation around
the surgical wounds. Nobody quite knew what caused it. Some
people thought it was a kind of chemical reaction between open
wounds and the oxygen in the air. British surgeon Joseph
Lister (1827–1912) had a different idea. He-
believed that the inflammations were caused, not by the air
itself, but by some kind of particle carried in it. When he heard
about Louis Pasteur’s research, he connected it to his own
observations. He became convinced that the wounds were
being infected by germs that lived in the air.
The problem now was how to get rid of the germs. He had
already tried cleaning the wounds, with little success. Finally, he
used a chemical called carbolic acid, which had been used to
treat sewage in a nearby town. After he began cleaning his
patients’ wounds with carbolic acid, they remained free of
infections.
Many people didn’t trust Lister’s techniques at first, but within
a few decades they had caught on. In 1878, his work inspired
the German surgeon Robert Koch to sterilize his surgical tools
with steam.
Today, surgery is conducted under antiseptic conditions, which
means that everything possible is done to keep the patient and
the surgical tools free of germs. Without antiseptic surgery,
even the simplest operation would still be a very dangerous
gamble .
