|Battle Against Disease| Harmful microorganisms enter the body
in one of four ways: |Through air, as in droplets of water from
the nose or mouth (whooping cough, measles, mumps, influenza,
tuberculosis and half of all human infections)| |Through unclean
food and polluted water (cholera, dysentery, typhoid fever,
diphtheria, mad cow disease)| |Through the bites of infected
animals and insects (malaria, rabies, bubonic plague, Rocky
Mountain spotted fever, Lyme disease)| |Through direct personal
contact (Ebola, herpes, syphilis, AIDS)| Sometimes the bodys
response is not strong enough to fight off the disease. Medical
science has developed vaccines to bolster the immune system.
Three types include |Vaccines from live bacteria| |Vaccines from
dead bacteria| |Vaccines from inactivated toxins produced by
bacteria| Some bacteria become harmless after being grown for
awhile in a laboratory, and when injected can produce immunity.
In the 1980s a leprosy vaccine was developed this way. Dead
bacteria are used in the va