Streptomycin

The discovery of streptomycin by microbiologist Selman Abraham Waksman (1888-1973; winner of the 1952 Nobel Prize in medicine) occurred in the mid-1940s. The discovery of this effective and safe antibiotic led to the taming of tuberculosis, or "TB." Streptomycin has also been found effective in treating several other infectious diseases.

The Search Begins with Soil Microbes

Prior to his most exciting discovery, Waksman, a Russian-born American microbiologist, had been engaged in a study of soil microbes for a number of years. One of his students, French-born René Jules Dubos (1901-1981), was searching for antibacterial substances in soil. In 1939 Dubos discovered the first antibiotic drug, gramicidin. Although it fought pneumococcus, staphylococcus, and streptococcus bacteria, it was too toxic (poisonous) for use in humans.

Waksman was inspired by Dubos's discovery. With the support of the Merck pharmaceutical company, he turned his attention to antibacterial substances found in soil. In 1941, he dubbed these substances "antibiotics." By 1958 he had discovered eighteen such drugs. Of these, streptomycin was the most important. Waksman isolated the antibiotic in 1943 and found it to be active against gram-negative bacteria. Eventually, streptomycin proved to be effective at fighting the tubercle bacillus. Because the tubercle bacillus can enclose itself in nodules in the body, it can remain dormant for years. When TB becomes active, it can strike any part of the body, but normally attacks the lungs. At the time Waksman developed streptomycin, the only treatments for TB were prolonged bed rest and nutritious food.

A man filters and subdivides streptomycin at the New Sterile Techniques Plant owned by Merck & Company.

Testing the Drug

Pathologist William Hugh Feldman (1917-) and bacteriologist H. Corwin Hinshaw (1902-) conducted the first clinical trials of streptomycin against tuberculosis. Feldman and Hinshaw first tested streptomycin on guinea pigs infected with tuberculosis. They found the drug to be nontoxic as well as highly effective. By 1945 Feldman and Hinshaw had conducted their first tests of streptomycin in human tuberculosis patients. The drug arrested the bacteria and reversed the disease. Feldman and Hinshaw's studies showed that the antibiotic was effective against a number of different forms of tuberculosis. These included TB of the skin, bones, lung, meninges, joints, and genito-urinary tract. The side effects caused by the drug included impairment of the sense of balance and deafness. These side effects proved to be temporary and could be minimized by controlling the dosage of the drug.

The Merck company agreed to turn over the rights for streptomycin to Rutgers University, which in turn licensed companies for production. In the late 1940s eight pharmaceutical companies began mass producing streptomycin. An estimated $1 million worth of the drug was provided for the largest clinical study of a drug ever undertaken, a study involving several thousand tuberculosis patients.

Other Uses for Streptomycin

Not only was streptomycin found to be effective and safe in treating tuberculosis, but eventually it was found to be active against 70 different types of bacteria which do not respond to penicillin including infections of the abdomen, urinary tract, pelvis, and meninges. Clinicians soon found additional drugs capable of destroying the TB bacillus. No less than 11 such drugs were isolated, providing physicians with a potent arsenal in the battle against TB. Using a combination of two or more drugs, doctors could strike at the stubborn microbes with great effectiveness. By the 1970s, the disease could be successfully treated in nearly all cases.

Tuberculosis continues to be the most deadly infectious disease in the world. It attacks thousands of people in regions where adequate medical treatment is not available. Recently, concern about the return of TB has been voiced in the United States. Many victims of immune deficiency diseases such as AIDS have been infected with TB. In addition, physicians are concerned about the large number of TB victims who abandon their medical treatment before it is complete. Despite the effectiveness of drugs like streptomycin, acts like this keeps the disease alive and increase the chance of it spreading to others.