The potential impact of coinfection on antimicrobial chemotherapy and drug resistance

Abstract

Across a range of pathogens, resistance to chemotherapy is a growing problem in both public health and animal health. Despite the ubiquity of coinfection, and its potential effects on within-host biology, the role played by coinfecting pathogens on the evolution of resistance and efficacy of antimicrobial chemotherapy is rarely considered. In this review, we provide an overview of the mechanisms of interaction of coinfecting pathogens, ranging from immune modulation and resource modulation, to drug interactions. We discuss their potential implications for the evolution of resistance, providing evidence in the rare cases where it is available. Overall, our review indicates that the impact of coinfection has the potential to be considerable, suggesting that this should be taken into account when designing antimicrobial drug treatments.

Keywords: coinfection; drug resistance; immune modulation; parasite interactions; resource competition.

Figure 1

Antagonistic to synergistic coinfections. Coinfection can have effects on focal pathogen density and replication. Different interactions, ranging from antagonistic to synergistic, can then have differing effects on chemotherapy and resistance. Species referred to in the figure: Streptococcus pneumoniae, Staphylococcus aureus, Clostridium difficile, Pseudomonas sp., Helicobacter pylori and Vibrio cholerae. Abbreviation: TB, Mycobacterium tuberculosis.