Decolonization and Pathogen Reduction Approaches to Prevent Antimicrobial Resistance and Healthcare-Associated Infections

Abstract

Antimicrobial resistance in healthcare-associated bacterial pathogens and the infections they cause are major public health threats affecting nearly all healthcare facilities. Antimicrobial-resistant bacterial infections can occur when colonizing pathogenic bacteria that normally make up a small fraction of the human microbiota increase in number in response to clinical perturbations. Such infections are especially likely when pathogens are resistant to the collateral effects of antimicrobial agents that disrupt the human microbiome, resulting in loss of colonization resistance, a key host defense. Pathogen reduction is an emerging strategy to prevent transmission of, and infection with, antimicrobial-resistant healthcare-associated pathogens. We describe the basis for pathogen reduction as an overall prevention strategy, the evidence for its effectiveness, and the role of the human microbiome in colonization resistance that also reduces the risk for infection once colonized. In addition, we explore ideal attributes of current and future pathogen-reducing approaches.

Keywords: Pathogen reduction; antimicrobial resistance; bacteria; decolonization; healthcare-associated infection; human microbiome; patient safety; transmission prevention.

Figure

Preferred attributes for decolonization and pathogen reduction approaches to prevent antimicrobial resistance and healthcare-associated infections. Examples of these approaches include the following: highly selective, e.g., selective digestive decontamination targeting aerobic gram-negative bacilli; limited distribution, e.g., nonabsorbable antimicrobial drugs; avoids cross-resistance, e.g., chlorhexidine biocide; high potency, e.g., preventing selection of resistant mutations; stable or reproducible, e.g., use of phages to decolonize or reduce bacterial burden; and microbiome protective, e.g., using the human microbiome to spare beneficial microbes.