Tiny Killers: When Bacteria and Viruses Attack

Tiny Killers: When Bacteria and Viruses Attack — page 3
SETTLING FOR GERMS In the early days of mankind when people roamed around hunting and gathering infectious diseases were probably rare People did not live close enough together for germs to spread or stay long enough near water sources to pollute them Disease on the Farm The development of farming some ten thousand years ago saved mankind from starvation and provided food for the first towns and cities But germs multiplied as people and farm animals began living close together sharing their germs and polluting the water Slow-moving water provided a breeding ground for parasites Cattle gave us tuberculosis and smallpox Dogs gave us measles 8 Chickens may have given us fl u