Mayo Clinic Radio: Antibiotic Resistance At least 2 million people in the U.S. become infected annually with antibiotic-resistant bacteria, and at least 23,000 people die each year as a direct result of these infections, according to the Centers for Disease Control and Prevention. Antibiotics have been used for more than 70 years to treat patients who have infectious diseases. Since the 1940s, these drugs have greatly reduced illness and death from infection. However, antibiotics have been so widely used for so long that the drugs have become less effective. Organisms the antibiotics are designed to kill have adapted.