Antimicrobials and Resistance

Forest W. Arnold, DO, MSc, FIDSA Assistant Professor, Division of Infectious Diseases

University of Louisville
Hospital Epidemiologist
University of Louisville Hospital
Louisville, KY

October 3, 2014


Although infection prevention traditionally has approached the problem of resistance primarily from the aspect of preventing transmission, more needs to be done to control how antimicrobials are commonly used. Antimicrobial use is the main selective pressure responsible for the increasing drug resistance seen in hospitals. Patients come to possess a resistant pathogen by either having their bacteria acquire a gene that codes for resistance or by transmitting bacteria that already have the resistance gene in place. The former takes days to weeks to develop, whereas the latter merely requires a handshake. To have an impact on antimicrobial use so as to reduce resistance, infection preventionists need a working knowledge of available antimicrobials, principles for their appropriate use, the mechanisms by which these drugs inhibit microbial growth, and the mechanisms by which microorganisms develop resistance. In addition, infection preventionists need to understand promising new strategies to improve antimicrobial use and how members of the infection prevention community can become more involved.