Engines of Our Ingenuity


No. 1527:
POLIO AND CLEAN WATER

by John H. Lienhard

Click here for audio of Episode 1527.

Today, we wonder where polio came from. The University of Houston's College of Engineering presents this series about the machines that make our civilization run, and the people whose ingenuity created them.

The muscle-crippling disease poliomyelitis -- polio for short -- had just come on the American scene when I was a child. The polio virus travels in water, so my parents wouldn't let me swim in public pools and beach areas. Indeed, one book on polio is titled The Summer Plague for just that reason. Today, polio is only a bleak memory for older Americans. It still returns to attack the muscles of its survivors as they age. But we've stopped seeing new cases.

Polio was pretty obscure before the twentieth century. There'd been some outbreaks in the eighteenth and nineteenth centuries, and most victims had been under the age of four. When I was young, the disease was still called Infantile Paralysis.

The really horrific polio epidemics began in 1916. By the early '50s it'd been striking some 30,000 people a year. Then the Salk vaccine appeared, and soon the virus was beaten.

So why did the early twentieth century produce those terrible epidemics? We had two clues, even before we knew how to deal with the virus. One was that polio attacked the middle class more than the poor. Indeed, one myth of seventy years ago said that black people didn't get polio. The other clue lay in the increasing age of victims. Victims of the 1916 epidemic were generally older than three, but ninety-five percent were still under the age of ten. In the 1947 epidemic, almost half the victims were ten or older.

The cause of the epidemics turns out to've been, of all things, improved hygiene. There was a time when everyone got polio. It was in everyone's drinking water. When it struck a very young child, the child would suffer a little diarrhea, bounce back, and then be immune. Polio was rarely severe enough at that age to cause severe damage, so we were hardly aware of it. Like measles, mumps, and chicken pox, the disease simply immunized the child.

Then, in the twentieth century, the industrial nations cleaned up their water supply systems. As they did, the general immunity disappeared. When polio did reach children over three and young adults, it didn't just cause diarrhea. It crippled and killed them.

Polio remained incurable. Massage therapies gave some relief. Franklin Roosevelt took his polio to Warm Springs, Georgia. George Washington Carver received a grant to develop a combined massage and peanut-oil therapy at the Tuskegee Institute. The fiery Australian nurse, Sister Elizabeth Kenney, swept into the American medical establishment in 1940. Her massage therapy dominated the treatment of polio until, and after, her death in 1952.

But massage therapies were after-the-fact treatments of polio. Once we had a vaccine to prevent polio, those therapies faded from our consciousness. So the most terrifying scourge of the early twentieth century came and went. It was a disease brought on by something new in human experience. Polio was the completely unexpected result of our new clean-water delivery systems.

I'm John Lienhard, at the University of Houston, where we're interested in the way inventive minds work.

(Theme music)


Paul, J. R., A History of Poliomyelitis. New Haven: Yale University Press, 1971.

Gould, T., A Summer Plague: Polio and its Survivors. New Haven: Yale University Press, 1995.

Cohn, V., Sister Elizabeth Kenney, the Woman Who Challenged the Doctors. Minneapolis: The University of Minnesota Press, 1975.

See also the Encyclopaedia Britannica articles on poliomyelitis. The word doesn't appear until the later editions. The 1970 edition has the longest article.

I am grateful to Thomas DeGregori, UH Economics Department, for suggesting the topic.



A March of Dimes poster to raise funds for the fight
against polio. This is from 1952, during the Korean
War and just before the Salk vaccine went into use.



The Engines of Our Ingenuity is Copyright © 1988-2000 by John H. Lienhard.