What causes disease? (Disease prevention).(Brief Article)

You probably know that the common cold and flu are caused by viruses that spread from person to person. Most viruses, bacteria, and other germs can pass from one person to another and cause disease. Diseases that can spread from person to person are called infectious diseases.

Not all diseases are infectious. Some are caused by chemicals in the environment. Those chemicals can damage cells and cause disease. For instance, asbestos can cause lung cancer in people who breathe asbestos fibers for long periods.

Some diseases are inherited. Parents can pass to their children the tendency to develop diseases such as hemophilia, muscular dystrophy, and cystic fibrosis. Those children can, in turn, pass the tendency to develop the disease to their children, and so forth. Inherited diseases are among the most difficult diseases to treat.

Still other diseases develop as people grow older and parts of their bodies wear out. Many aging people develop arthritis as their joints wear down and become inflamed.

In kids, most diseases are either infectious (such as colds, flu, or chicken pox) or inherited (such as cystic fibrosis, a lung disease, or hemophilia, a blood disease).

The Long and Short Of Disease

When you catch a cold, you probably feel terrible for a few days. Diseases that last a short time are called acute. Most acute illnesses aren't serious and can be fought off by the body's own defenses. But acute diseases such as pneumonia (a lung infection) or meningitis (an infection of the membranes covering the spinal cord) are more difficult to treat and can result in death.