The epidemiology of antimicrobial resistance

Antimicrobial resistance is increasing at an alarming rate, leading to profound crises in the treatment of common infectious diseases. Although bacteria have "natural" resistance to some antibiotics, most resistance can be attributed to over-prescription of antibiotics by physicians, over-the-counter use of antibiotics in many countries, "indigenized" use of antibiotics in developing countries, and application of antibiotics for growth promotion and treatment and prevention of infection in animal husbandry and farm fishing. The development of antimicrobial resistance involves four factors: mutation, directional selection, amplification, and geographic dissemination. Although the pharmaceutical industry is endeavoring to develop new classes of antibiotics, it is unlikely that new agents alone will solve the antimicrobial resistance problem. Rather, a coordinated, multidisciplinary approach is required, including reduction in inappropriate use of antibiotics in humans and agriculture, education of consumers, and application of established infection control techniques to limit the spread of resistant microorganisms in hospitals and other settings that favor amplification of resistance.