Resistance Trends and Susceptibility Profiles in the US Among Prevalent Clinical Pathogens: Lessons from Surveillance

Since the advent of their discovery in the 1930s, antibiotics have served with great success on the front lines in the war against bacterial infection. A consequence of this success and widespread use was the inevitable evolution and emergence of resistance among bacteria from the resulting selective pressure. In the Golden Age of antibiotics (1940s–1960s), discovery of various new classes of antimicrobial agents outpaced the development of resistance by delivering new agents with different mechanisms of action that were effective against the resistant organisms of the day. In contrast, during the following period, there was a lack of development of novel classes of agents in favor of the chemical and structural modification of agents within established classes. While the development of novel classes or agents with activity against resistant organisms has slowed, the emergence and spread of resistance among bacteria has continued.