Antibiotics are medicines that are lethal to bacteria that cause infections.

Antibiotics have been used since the 1930s to treat or prevent a wide variety of infections. Prior to the advent of antibiotics, there were few effective ways of combating infections caused by bacteria. Illnesses such as pneumonia, tuberculosis, and typhoid fever were often considered untreatable. Even minor bacterial infections could potentiate life-threatening illnesses.

Since the introduction of antibiotics in the mid 1930s, physicians and patients have come to depend on these drugs to treat everyday bacterial infections from sore throats and urinary tract infections, to meningitis and tuberculosis. These drugs are also used to prevent infections before, during, and after surgery. Many new antibiotics have been developed over the years, and by the 1970s, some scientists claimed infectious diseases were on the verge of being eliminated. In recent years, health experts have noticed that antibiotics are becoming...