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Inland aquaculture contributed by three major fish groups, including carps, tilapias, and catfish plays a vital role in global food security and nutrition, particularly in low and middle‐income countries. However, the sustainable development of this sector is hampered by disease epidemics, especially those caused by bacteria such as Aeromonas species. At least eight pathogenic motile Aeromonas species (A. hydrophila, A. veronii, A. jandaei, A. caviae, A. sobria, A. bestiarum, A. dhakensis and A. schubertii) have been reported in aquaculture with some causing up to 100% mortality during disease outbreaks. Simultaneously, emerging multidrug‐resistant Aeromonas due to a long‐inappropriate use of antibiotics is alarming and highlights a global public health concern and negative socioeconomic impacts. Here, we provide a comprehensive overview of motile Aeromonas infections, antibiotic use and antimicrobial resistance of Aeromonas species. This contribution also highlights the non‐antibiotic approaches (the solutions for preventing or treating of bacterial diseases without resorting to antibiotic use) to control motile Aeromonas infections. In addition to the current state of knowledge and limitations of each prophylaxis/therapy, perspectives for future research are discussed critically, including oral/immersion multivalent vaccines, microencapsulated synbiotics, exogenous metabolites, and novel lytic bacteriophage cocktails. Some emerging applicable nanotechnology themes such as nanovaccines, nanobioactive compounds, and nanobubbles are also included in this review. In summary, combating motile Aeromonas infections in aquaculture, including multidrug‐resistant aeromonads, as well as other bacterial diseases, is a lengthy battle that requires a strategic combination of multiple non‐antibiotic approaches coherent with the One Health philosophy. [ABSTRACT FROM AUTHOR]

Mass mortality events are routinely reported in bivalve cultivation practices worldwide with significant economic consequences for the global aquaculture industry. Major contributors of these bivalve losses are infections caused by viruses and bacteria whose molecular action mechanisms are still not fully understood. This major bottleneck for shellfish cultivation presents an opportunity for fundamental research that can generate practical tools for reliable health assessments. To this end, newly developed omics approaches are likely to facilitate knowledge acquisition, especially if applied in conjunction with established and emergent immunological techniques. In recent years, various omics technologies (e.g. genomics, transcriptomics, proteomics and metabolomics) have been used to study the Pacific oyster mortality events associated with detection of ostreid herpesvirus type 1 (OsHV‐1) and Vibrio bacteria. These new approaches, especially when used in combination have significantly improved our understanding of this syndrome and associated diseases. In this paper, we review the current omics technologies that have been employed to investigate the interactions between Pacific oyster Crassostrea gigas and pathogens (e.g. OsHV‐1 and Vibrio sp.), infection mechanisms, host susceptibility and resistance. Herein, we also highlight some of the current challenges and future directions of omics approaches in shellfish health research, including disease detection, diagnosis and treatment. [ABSTRACT FROM AUTHOR]

From the first detection in the Eastern oysters (Crassostrea virginica) in 1972, herpes‐like viruses/herpesviruses have been identified in at least 20 bivalve species and have caused massive mortalities in six cultured species of bivalves. Among them, the Pacific oyster (Crassostrea gigas) is most threatened by massive mortalities associated with detection of Ostreid herpesvirus 1 (OsHV‐1) and its variants. These mortality events have been reported in more than 12 countries, and OsHV‐1 itself has been reported in 15 countries worldwide. Traditionally, the genotype OsHV‐1 (or OsHV‐1 Var) is the main contributor to bivalve mortalities, but the emergence of variants (e.g. OsHV‐1 μVar and related ones, acute viral necrosis virus—AVNV, OsHV‐1‐SB) is now responsible for new mortality outbreaks in Pacific oysters and other bivalve species. In addition to OsHV‐1, Vibrio bacteria and other abiotic and host factors also significantly contribute to mortality outbreaks. To this end, the current contribution aims to synthesize the body of literature on our current knowledge of these mass mortality events to provide insights into the role of each risk factor and complex interactions in the disease process. Specifically, this review encompasses our current knowledge and critical gaps. Important suggestions for future investigation are also presented. [ABSTRACT FROM AUTHOR]