[2] E. tarda has a worldwide distribution and can be found in pond water, mud, and the intestine of fish and other marine animals.

The creation of the species was suggested by Ewing and colleagues in 1965 in order to cover 37 different strains that mainly were found in fecal materials.

Edwardsiella tarda was established as a legitimate genus and species through studies at the Walter Reed Army Institute of Research by Don Brenner.

This might have addressed the arguments between the Japanese and American investigators with regard to the difficulty of differentiating isolates from fish and humans by the time and ended up classifying all into same species i.e. Edwardsiella tarda.

[4] E. tarda produces hydrogen sulfide and is unable to ferment lactose, making it indistinguishable from Salmonella on routine laboratory media.

Infection can cause organomegaly, ocular disease, rectal prolapse, ecchymosis, and erosions on the skin, inflammation of the gills, oedema, ascites, abnormal behavior, and haemorrhage throughout the body.

However E. tarda can be cultured on specific growth mediums such as brain-heart infusion agar and techniques such as indirect fluorescent antibody testing, ELISA and loop-mediated isothermal amplification (LAMP) can be used to confirm diagnosis Antibiotics should be used to treat infected fish.

[3] Management factors such as reducing stress and stocking density can help prevent disease along with maintaining suitable sanitation of water.

These intra-specific variations that they were looking for occur in other parts of the world where E. tarda is found and they were hoping to discover how similar levels may be in the United States.

This study will be used to improve the accuracy of "molecular diagnostics to better understand the role these genetically distinct E. tarda groups play in fish health.