Virulence Determinants of Aeromonas Species Implicated in Fish Diseases and Control of Infection: An overview

Aeromonads are halophilic, non-spore forming, Gram-negative rods which are ubiquitous in aquaculture and foodstuffs. Members of genus Aeromonas are abundant water inhabitant bacteria that were recovered from lakes, rivers, swamps, chlorinated water as well as food stuff as fish, meat, seafood, vegetables, and processed foods. Aeromonas species are opportunistic pathogens that affect many aquatic animals and human. These pathogens cause septicaemia, ulcerative and haemorrhagic diseases, and mortality in different fish species. They possess large number of virulence factors in addition to inherent resistance to various antimicrobials and ability to form biofilms with the help of quorum sensing. This review focuses on the pathogenic potentials of Aeromonas species which regarded as multifactorial and dependent on the presence of different virulence factors that enable bacteria to colonize, invade, and defeat the host’s immune defences. This review also provides an update on the taxonomy, ecology, and control of Aeromonas infection in fishes.