What excatly are antibiotics

Most diseases that attack the human body are caused by tiny living things called bacteria. Antibiotics are a group of medicines or drugs that help the body fight and destroy harmful bacteria. (Anti-, meaning "against," and biotic, meaning "living," are words taken from the Greek language.) Although they are used as medicines, antibiotics themselves are taken from living things—tiny forms of plant life found either in the soil or in mold, a kind of plant growth that lives on rotting wood, old bread, and other things.

Some molds are poisonous to human beings, but others are harmless and sometimes very useful. The green mold used in cheese belongs to a family of molds known as Penicillium. From one of these molds, Penicillium notatum, comes the wonderful antibiotic called penicillin. Penicillin was the first of the antibiotics. It was accidentally discovered by Dr. Alexander Fleming of Scotland when he was working in the laboratory of St. Mary's Hospital in London, England, in 1928. Dr. Fleming was trying to kill some dangerous bacteria called staphylococci. One day he noticed that a glass dish in which he was growing some of these staphylococci had become covered with a green mold—and that at the same time the staphylococci had all died! After ten years of work, with the aid of other doctors, Dr. Fleming produced the drug we now call penicillin. During World War II it saved the lives of thousands of wounded men. There is a separate story about PENICILLIN. Antibiotics do not kill bacteria, but stop their growth and prevent them from increasing. This gives the leucocytes in the blood a chance to destroy them. Leucocytes are tiny, round white cells that can be seen only through a microscope. T

hey float in the blood and attack harmful bacteria in the blood. The human body also fights bacteria by making certain substances or chemicals called antibodies in the blood, and the antibodies kill bacteria. However, sometimes the bacteria increase so fast and there are so many of them that the body cannot kill them off fast enough and when this happens the sick person usually dies. By preventing the bacteria from increasing in number, antibiotics give the body a chance to create antibodies in time to destroy the bacteria of disease. Many of the antibiotic drugs have mycin or mycetin in their names. This is because the fungus growths (one of which is mold) are called myceles in technical medical language.

The first of these drugs to be successful was streptomycin. This was discovered by Dr. Sel- man Waksman at the Agricultural Experiment Station of Rutgers University in New Brunswick, New Jersey. Dr. Waksman was born in Russia, but came to the United States as a youth and studied at Rutgers. He became interested in actinoniyceles. a family of plants—so tiny they can be seen only through a microscope—that are found by the millions in the soil in almost any part of the country. Convinced that actinomycetes could kill some of the bacteria that cause disease in human beings, Dr. Waksman began experimenting in 1940 with the different kinds of plant life in this family. In 1943, Dr. Waksman and some of his assistants produced streptomycin from one of the actinomycetes. This drug attacked diseases against which penicillin did not work, for example tularemia, a dangerous fever that human beings get from rabbits; certain diseases of the bladder and kidneys; blood poisoning; and tuberculosis, a sickness from which many people were dying each year. Scientists have been working ever since to discover new antibiotics, and they have discovered many.

There are aureomycin, terramycin, and several others that can be used against diseases that penicillin and streptomycin do not stop. Also, some persons who are made sick by some of the antibiotics find that they can take others without bad effects. The antibiotics are the greatest advancement medical science has made in half a century. Several diseases that used to kill people are no longer considered even dangerous, thanks to the antibiotics. One of the strange things about antibiotics which science is still unable to explain is the amazing way in which they help farm animals grow twice as fast as they usually do. When antibiotics are mixed into the feed given to chicks, calves, and little pigs, these animals grow much faster and larger than those that get the usual feed.