MEDICAL ASSISTS FOR BODY DEFENSES
On a May day in 1796, an
English country physician, Edward Jenner, opened a new era in combatting disease-the
age of immune therapy as a preventive. A smallpox epidemic had struck, but not
as hard in rural areas as in larger cities. Jenner wondered about that and
about the cow- pox infection many people in his village contracted from cattle.
Cowpox caused only a running sore that quickly healed. But was the disease
related in any way to smallpox? Did exposure to cowpox provide immunity against
smallpox? To test his theory, Jenner made a small cut in an arm of an 11-year-
old boy patient and applied to it pus taken from a cowpox sore on a dairymaid's
hand.
The boy developed a mild case of cowpox and was soon over
it. Then Jenner made the critical test, applying to cut pus from a smallpox
patient. The boy did not get smallpox; he was immune. Here was the first use of
the fact that a mild attack of some diseases may prevent full-fledged illness
from occurring. It took a long time before Jenner's work was accepted.
Almost a
century went by before Louis Pasteur of France used much the same technique to
inoculate against rabies. Since then-slowly at first, now with increasing
rapidity -vaccines have been developed to protect against many diseases.
Whatever the vaccine, the principle is the same: to introduce material
specially treated so that, without causing actual disease, it causes the body
to develop defenses against the disease.
The immunity produced by such vaccination is active; the
individual himself manufactures antibodies that will protect him. Another form
of immunity, passive, involves injection of antibody material created in the
body of another person or an animal. Passive immunity usually does not last
very long.
Everyone should be immunized against these dangerous diseases:
smallpox, diphtheria, polio, tetanus, sometimes typhoid fever, and, in the case
of children, whooping cough and measles. Inoculations are readily obtainable,
virtually free of discomfort, can be administered by family physician or
pediatrician, and are available free, or at little cost, so lack of money
should not, and must not, keep anyone from being immunized.
Any public health
department or hospital can provide information about low-cost or no-cost
immunizations. It is particularly important to give children the advantages of
protection against diseases that could be extremely dangerous for them.
