Donald Marinkovich, age 11, of Chrisholm, Minn., for his question:

WHAT CAUSES LEPROSY?

A Norwegian physician by the name of G. Armauer Hansen identified leprosy in 1874. Today the infliction is also called Hansen's Disease. Actually, it is a very ancient disease which probably existed in India, Egypt and China more than 2,500 years ago. It is mentioned in the Bible. Leprosy spread throughout the Pacific area during the early 1800s.

Leprosy is caused by a rod shaped bacterium. It attacks the skin and nerves of the body and makes the skin swell and become discolored and lumpy. It is feared because it can damage a person's appearance although it rarely causes death.

Leprosy is contagious but reports on how it can spread have been greatly exaggerated. To get the disease, most doctors agree, a person must have very low resistance and also live in contact with a person whose body holds great numbers of the leprosy germs.

Children are more likely to get the disease than are adults. Children whose parents have severe leprosy have about a 30 percent chance of getting it, although the disease only persists in about six percent of these cases.

It is said that only about 2,000 cases of leprosy exist in the United States today. It has been estimated that between five and 12 million cases can be found in the world, with about 85 percent of the patients living in one of six countries: Zaire, Nigeria, Japan, Indonesia, India and China.

Leprosy most of the time is a mild disease that is often arrested without treatment. Skin discolorations usually disappear or leave only faint traces. If not checked, however, it can cause muscles in the hands and feet to become weak. In severe cases, toes and fingers may curl inward. Early treatment is important since deformities and other physical handicaps can often be avoided. Sulfone drugs are used in the treatment.

There was a time when most leprosy patients were separated from the general population and put into special hospitals called leprosariums. Leprosariums still exist today in some countries but they are used chiefly as research centers. Leprosy patients are now treated as outpatients in clinics for the most part.

Leprosy becomes inactive with most patients after they undergo a series of treatments. However, the cure is not always permanent and regular checks with the doctor must be continued.

While leprosy is contagious, it isn't a disease that need be feared as it was just a few years ago. Medical statistics show that leprosy develops in only about five percent of those persons who are married to leprosy patients. In addition, it is rare for doctors and nurses who care for leprosy patients to contract the disease.

There are two types of leprosy: tuberculoid which attacks the nerves and lepromatous leprosy which attacks the skin