Bacterial infections in fish and strategies for biological control

Abstract

In recent years, fish farming has encountered growing challenges due to the rise of various pathogens and increasing resistance to traditional treatments. Fish diseases now account for around 20% of production losses, and this figure can exceed 43% during outbreaks. Understanding how pathogens interact with their hosts and the factors contributing to antibiotic resistance is essential for developing effective solutions. This article focuses on emerging fish pathogens and highlights strategies such as biocontrol, immune system stimulation, and immunoprophylaxis to help manage these diseases. Bacteria like Aeromonas spp. and Edwardsiella spp. have become more prevalent, with Aeromonas species being particularly diverse, which complicates diagnosis and vaccine development. Likewise, Edwardsiella species infect a wide range of fish, making control efforts even more challenging. These pathogens cause significant losses in fish health, productivity, and quality, raising costs and posing environmental risks due to the overuse of antibiotics. The issue also explores how bioinformatics, genomics, and other advanced technologies can improve pathogen detection, vaccine development, and the selection of fish with natural disease resistance. It also stresses the need for better biosecurity, standardized diagnostic methods, and alternative approaches to antibiotics, such as probiotics and prebiotics. Overall, the articles in this issue emphasizes the critical importance of understanding pathogens to develop more sustainable and effective practices in aquaculture.