The concepts of what constituted health and disease at
the beginning of the last century were far different
from those of this century. In most of the industrialized
nations of the world, people now are living longer
and enjoying a healthier lifestyle. Much of this has been
made possible by recent advances in science and technol-
3
C H A P T E R 1 Concepts of Health
and Disease
Georgianne H. Heymann
Carol M. Porth
ogy. There has been an increased knowledge of immune
mechanisms; the discovery of antibiotics to cure infections;
and the development of vaccines to prevent disease,
chemotherapy to attack cancers, and drugs to control the
manifestations of mental illness.