Philip J. Goscienski, M.D.
Prior to the Agricultural Revolution, the period we call the Old Stone Age, there were no epidemics because the population was too sparse to support one. Before we began to congregate in small villages, then towns and cities we were wanderers who followed the food supply. For tens of thousands of years such bands consisted of about 15 to 50 individuals. Some locations, especially along the edges of lakes and seas, may have allowed relatively permanent habitats, but this was not the rule.
When our ancestors figured out that it was easy to raise plants and to breed animals instead of hunting them it permitted groups of people to remain in one area. Small settlements became villages, then towns. Wherever this occurred the health of the population deteriorated, sometimes disastrously. In every population group that archeologists have studied, infectious diseases and shortened lifespan followed the transition from the hunter-gatherer to the agricultural lifestyle.
Epidemics appeared for the first time under these conditions. Crowding allowed diseases such as influenza to spread quickly. When ponds, lakes and streams that served as water and food sources became contaminated with human waste it permitted completion of the life cycle for numerous animal parasites that spread easily among the human population. In raising animals and in sharing our living spaces with them we shared their diseases. Dependence on only a few crops meant that drought, flood, pests or blight left famine in their wake. A starving population cannot resist infection. As hunger-stricken individuals migrated in search of more food, they spread disease.
Avian influenza, what the media call bird flu, could not have gotten very far among humans during the Stone Age although the virus could have killed lots of wild birds. Not only were there no domestic flocks of chickens, ducks or geese 100,000 years ago, there were no efficient hunting methods either. Humans developed the bow and arrow only about 20,000 years ago and net-making is probably an even later invention.
The avian flu virus has probably infected birds for hundreds of thousands of years but if it did pass to a human it probably didn't get very far. How different today! The virus can easily pass from one chicken to another when birds are jammed together by the thousand and each one is entitled to only a 7-inch square of living space.
In order to cause an epidemic the virus has to combine with a human virus and still maintain its ability to spread quickly and to invade humans. The scattered and sparse bands of the Stone Age didn't provide the conditions that make that possible but our crowded, jet-setting populations certainly do.
Modern epidemics spread in the same way today that they did a few thousand years ago, but much faster. The Black Death took months to spread through Europe. SARS crossed the Pacific Ocean in hours. Progress comes with a price.
Philip J. Goscienski, M.D. is the author of Health Secrets of the Stone Age, Better Life Publishers 2005. Contact him at firstname.lastname@example.org.