Hafnia alvei: a Pathogen Causing Infectious Intussusception Syndrome (IIS) in Farmed Channel Catfish Ictalurus punctatus

Abstract

Infectious intussusception syndrome (IIS) is a serious problem, causing severe economic losses in farmed channel catfish Ictalurus punctatus. Limited information is available on Hafnia alvei as a causal agent for this disease. In this study, a virulent strain, temporarily named HN01, was isolated from diseased channel catfish suffering from infectious intussusception syndrome, and identified through phylogenetic analysis and phenotypic characteristics. A phylogenetic tree was constructed to examine isolate HN01 and compare it to other known isolates. Isolate HN01 has also been found to be susceptible to aminoglycosides, quinolones and sulfonamides drugs for veterinary use in aquaculture when screened against a range of common antibiotics. To the best of our knowledge, this is the first report of infectious intussusception syndrome caused by Hafnia alvei in farmed channel catfish.