By Donella Meadows

–May 25, 1995–

Overexcited reporters are calling the Ebola virus, which is killing people in the cities and villages of Zaire, “highly contagious.”  It is not.  Ebola is deadly if you catch it, but it is nowhere near as infectious as the common cold — thank heaven.

Richard Preston’s timely book The Hot Zone documents previous Ebola epidemics, including one in a monkey house in Reston, Virginia. The book makes clear what a horrible fate it is to be infected with Ebola.  (Don’t read alone on a dark night Preston’s description of what happens as Ebola turns your internal organs to soup.)  If you get Ebola, it’s likely to kill you.  In central Africa the mortality rate approaches 90 percent.

But Preston’s book also illustrates that Ebola is not easy to catch.  Doctors and nurses get spattered with the blood of its victims, but only a few are infected.  One sufferer drags himself onto a commercial flight, vomits in mid-air, and no one on the plane gets the disease.  Experts from the Centers for Disease Control fearfully enter the Reston monkey house wearing virus-proof space suits, but the people who care for the monkeys don’t get sick.

It’s important to use words carefully when panic can lead to abandonment of sick people or even of whole communities.  Ebola, like AIDS but on a faster time scale, is lethal, but not highly contagious.  With proper precautions one can serve its victims without endangering oneself.

It’s also important to be careful how we explain the emergence of this virus.  In Africa they’re blaming it on stolen diamonds and a curse.  In our part of the world explanations are just emerging — poor health care in Africa, the Belgian colonial legacy, the corrupt Zaire government.

I suggest a longer-term, scientific explanation.

It’s a law of ecology that if you increase the food supply and living space of any species, that species will multiply.  Till up a patch of good soil and you’ve made a perfect breeding place for weeds.  Plant corn all over the Midwest and you invite explosions of corn-eating pests.  Cover the planet with human beings, and you’re setting out a feast for microbes that inhabit the human body.

In 1950 Africa had 222 million people.  Now it has 744 million.  In 1950 the world had 2500 million people.  Now it has 5700 million.  Ecologists would be amazed if these population increases did not lead to outbursts of human pathogens.

According to another ecological law, critters that multiply fast can adapt rapidly to change.  People are clever, but microbes are prolific.  They conduct trillions of experiments at a time to get around our defenses.  Spray the cornfield with pesticides often enough, and the pests will become resistant.  Chlorinate water or douse the world with antibiotics, and the microbes will start liking chlorine and eating antibiotics.  Turn wildlife habitat into human habitat, and viruses will jump from wildlife to humans.

There’s a third ecological law that no one likes, but it’s as indisputable as the others.  A population can’t grow forever.  If it does not stop by controlling its own fertility (we are the only species on earth that has the intelligence to do that), something else will stop it.  That something could be a lack of food or water or space.  In our case, it could be violent self-destruction.  It could also be a predator or parasite or pathogen.

Many ecologists consider population control by pathogen quite likely.  In his 1968 book The Population Bomb, biologist Paul Ehrlich wrote a fictional scenario in which another rare African microbe, Lassa fever, spreads through the world and kills more than a billion people.  In 1976 there was an actual nationwide search for 100 people who had been on a plane flying back from Africa with a Peace Corps nurse who subsequently broke out with Lassa fever.  That tiime, fortunately, there was no epidemic.

To blame Ebola on population growth is not to blame Africans alone.  Africa’s population is indeed growing, and out of Africa have come Ebola and Lassa and (probably) AIDS.  Asia’s population is growing, and out of Asia comes a steady succession of new flus.  If one of them ever turns out to be deadly, then we really will have a plague that is highly contagious.  Our own population is the fastest-growing in the industrial world, and out of North America have come Hanta virus and Legionnaire’s disease and Lyme disease.

Rapid population growth is strongly associated with poverty and illiteracy and desperation.  If there is an alternative to population control by worldwide pandemic, it lies in family planning and in ending poverty — which wouldn’t be so hard to do, if we ever committed ourselves seriously to doing it.

Note to the welfare-haters and isolationists in Congress: this is not the time to eliminate either domestic poverty programs or foreign aid.  This is the time to make them more effective and efficient, because they are as vital to our national security as anything the Pentagon can do.

Copyright Sustainability Institute 1995