Bacteriophage therapy: exploiting smaller fleas.

Although bacteriophages have been used for the treatment of patients with bacterial infections in some regions of the world for >9 decades, adequate clinical trials of the safety and efficacy of the treatment have not been reported. The increasing problem of antibiotic resistance has, however, rekindled interest in this approach to therapy. Although potentially significant obstacles to systemic administration of phages exist, topical and oral administration of phages and/or phage products, such as lysins, are feasible in the short term. In addition to exploitation of the effects of native phages and phage products, bioengineering of phages will allow directed specificity and their use as delivery systems for antimicrobial and antivirulence molecules. This brief overview of the history and status of phage therapy, along with speculation about its future, provides a background for understanding of this imminent therapeutic modality.