Sanitation measures such as the use of sewers, landfills, isolation, and safe food handling are important in controlling the spread of organisms that cause disease. Improving sanitation to prevent disease has contributed more to saving human life than any advance in medical treatment.
Learning Goal 2
The ability to measure the level of substances in body fluids has made it possible for physicians to better diagnose illnesses and monitor the effects of the treatments they prescribe.
Learning Goal 3
It is possible to manufacture complex chemical substances such as insulin and hormones that are normally found in the body. They can be used by individuals whose own bodies do not produce the amounts required for good health.
Learning Goal 4
As the knowledge of how cells in the body detect and fight invaders has grown, the transplantation of tissue or whole organs has become increasingly common. New materials that are durable and less likely to be rejected by the immune system now make it possible to replace some body parts and to implant devices for electrically pacing the heart, sensing internal conditions, or slowly dispensing drugs at optimal times.
Learning Goal 5
Many diseases are caused by bacteria or viruses.
Learning Goal 6
If the body's immune system cannot suppress a bacterial infection, an antibacterial drug may be effective—at least against the types of bacteria it was designed to combat. Less is known about the treatment of viral infections, especially the common cold. However, more recently, useful antiviral drugs have been developed for several major kinds of viral infections, including drugs to fight HIV, the virus that causes AIDS.
Learning Goal 7
Increased knowledge about nutrition has led to the development of diets containing the variety of foods that can help people live longer and healthier lives.