Edwardsiella piscicida: a significant bacterial pathogen of cultured fish

Abstract

Edwardsiella piscicida, a Gram-negative, facultative aerobic pathogen belonging to the Enterobacteriaceae family, is the etiological agent of edwardsiellosis in fish and a significant problem in global aquaculture. E. piscicida has been reported from a broad geographical range and has been isolated from more than 20 fish host species to date, but this is likely to be an underestimation, because misidentification of E. piscicida as other species within the genus remains to be resolved. Common clinical signs associated with edwardsiellosis include, but are not limited to, exophthalmia, haemorrhages of the skin and in several internal organs, mild to moderate dermal ulcerations, abdominal distension, discoloration in the fish surface, and erratic swimming. Many antibiotics are currently effective against E. piscicida, although legal restrictions and the cost of medicated feeds have encouraged significant research investment in vaccination for the management of edwardsiellosis in commercial aquaculture. Here we summarise the current understanding of E. piscicida and highlight the difficulties with species assignment and the need for further research on epidemiology and strain variability.

Phenotype, Virulence and Immunogenicity of Edwardsiella piscicida Cyclic AMP Receptor Protein (Crp) Mutants in Catfish Host

“…To date, antimicrobial susceptibility testing shows that E. piscicida strains isolated from different hosts and geographical regions are susceptible to most commonly used antibiotics for the treatment of edwardsiellosis [4]. However antibiotic abuse represents a problematic method of treating bacterial infections in the aquaculture industry and has led to the evolution of multi-drug resistance strains [5].…”

A Spontaneous Outbreak of Systemic Edwardsiella piscicida Infection in Largemouth Bass Micropterus salmoides (Lacépède, 1802) in California, USA

“…Phenotypically indistinguishable from one another, molecular analysis has revealed fish-associated strains of E. tarda often represent one of two recently recognized taxa, E. piscicida (Abayneh, Colquhoun, & Sørum, 2013;Griffin et al, 2013;Yang et al, 2012) and Edwardsiella anguillarum (Shao et al, 2015), which can exhibit varied pathogenicity in different hosts (Reichley, Ware, Greenway, Wise, & Griffin, 2015;Reichley et al, 2018). Edwardsiella piscicida, formerly known as "typical fish pathogenic E. tarda" (Griffin et al, 2014;Sakai, Yuasa, Sano, & Iida, 2009;Yamada & Wakabayashi, 1999), has emerged as a significant pathogen of cultured freshwater and marine teleosts (Reichley et al, 2017;Buján, Toranzo, & Magariños, 2018;Griffin et al, 2018) and has been reported in an elasmobranch (Camus et al, 2016).…”

Performance of Channel Catfish and Hybrid Catfish in Single‐Batch, Intensively Aerated Ponds

“…; Buján et al. ). Recent studies indicated that E. piscicida is 10 times more lethal in hybrids than in Channel Catfish (Reichley et al.…”

“…Higher concentrations of potentially toxic nitrogenous wastes and chronic episodes of infectious diseases (septicemias caused by Edwardsiella ictaluri for Channel Catfish and E. piscicida for hybrids) could be the main reasons for reduced survival. Edwardsiella piscicida continues to garner attention as a significant pathogen in global aquaculture 412 Buján et al 2018). Recent studies indicated that E. piscicida is 10 times more lethal in hybrids than in Channel Catfish (Reichley et al 2017a(Reichley et al , 2017b, and assessment of diagnostic case submissions to the Aquatic Research and Diagnostic Laboratory at the Thad Cochran National Warmwater Aquaculture Center revealed that hybrids accounted for approximately 90% of suspect E. piscicida cases from 2013 to 2017 (Griffin et al 2019).…”