Would Bacteriophages Be a New Old Complement to Antibiotics in Aquaculture?

Abstract

The rise of antibiotic-resistant bacterial strains is a global concern in many sectors, such as aquaculture, as described in chapter “The Rise and Fall of Antibiotics in Aquaculture.” To counter this phenomenon, several alternatives or complement to antibiotics have been investigated. Here, we will look at one of those proposed strategies that of using bacteria-specific viruses, called bacteriophages, or commonly phages. Since their discovery in the early 1900s, bacteriophage treatments have had a fleeting popularity in Western countries due to several scientific reasons as well as in some cases, political motives. Only recently, with the appearance of multidrug-resistant bacterial strains, a new craze for phage therapy appeared in Western countries. In an aquaculture context, some studies have shown promising results for the treatment of fish diseases using phages. More specifically, the experimentations with phage cocktail against A. salmonicida, infectious agent of furunculosis in salmonids, both in vitro and in vivo, provide an interesting foundation for future alternative treatments. However, since phages and bacteria are evolving entities, this biological war is far from over. The presence of phage-resistance mechanisms in bacteria and other technical aspects of phage therapy in aquaculture are factors to consider before having any applicable treatments.