Breaking paradigms: Reconsidering the role of harmless vibrios in shrimp health

Vibriosis is a leading cause of economic losses in the shrimp industry worldwide, affecting both larvae and juveniles. Vibrio species (Vibrio spp.) are ubiquitous in marine and aquaculture environments, and their ability to thrive in warm, nutrient-rich conditions makes them omnipresent in shrimp microbiota. While pathogenic species such as Vibrio parahaemolyticus are responsible for acute hepatopancreatic necrosis (AHPND), there is increasing evidence on non-pathogenic Vibrio strains that can naturally limit the proliferation of pathogenic species. This review examines the environmental and ecological factors that help explain the predominance of Vibrio spp. in aquaculture systems and synthesizes the current knowledge on how microbial imbalance caused by pathogenic vibrios, particularly V. parahaemolyticus, affects shrimp health. We highlight the emerging evidence that beneficial Vibrio strains can improve microbiota stability, modulate immune responses, and competitively exclude pathogens. The focus is on Vibrio diabolicus (Ili strain) and its potential role in strengthening shrimp resilience against pathogenic Vibrio spp. Biosecurity considerations and challenges in incorporating beneficial Vibrio spp. into vibriosis management strategies are also addressed. By reframing Vibrio as both threats and potential allies, this review proposes a new perspective for developing microbiome-based approaches for the sustainable control of vibriosis in shrimp aquaculture.