Innovative biocontrol strategies in aquaculture using phage therapy and quorum quenching

Aquaculture plays a vital role in global food security, providing nutrition to billions and contributing significantly to the economy of many countries. As the sector grows, particularly in regions like India, the need to address health challenges in farmed species becomes critical. The major challenge is to control diseases caused by members of Aeromonas , Klebsiella , Edwardsiella, Vibrio , Pseudomonas , and other bacterial species, which result in substantial economic losses. The intensification of farming practices exacerbates these problems, leading to increased pathogen load and greater reliance on antibiotics. However, the overuse of antibiotics contributes to the development of antimicrobial resistance (AMR), complicating disease management with some strains emerging as multiple antibiotic resistant. This has driven interest in alternative strategies, with the latest being phage therapy and quorum quenching (QQ). Phage therapy employslytic bacteriophages, primarily with a DNA genome, to target specific bacterial pathogen(s), provide a promising, highly selective, and self-replicating solution. On the other hand, QQ disrupts bacterial communication systems established via quorum sensing (QS), which regulates biofilm formation and virulence factor expression in pathogens. By targeting these systems, QQ reduces bacterial virulence without killing the bacteria directly, thus avoiding selective pressure and lowering the chances of resistance development. Both phage therapy and QQ represent eco-friendly, innovative alternatives to antibiotics, with the potential to reduce disease impact in aquaculture. This chapter explores these strategies in depth, examining their mechanisms, applications, and effectiveness in combating bacterial infections in aquaculture and discusses the challenges and prospects for their integration into sustainable farming practices.