title: Detection of goldfish haematopoietic necrosis herpes virus (Cyprinid herpesvirus-2) with multi-drug resistant Aeromonas hydrophila infection in goldfish: First evidence of any viral disease outbreak in ornamental freshwater aquaculture farms in India.
abstract: This outbreak report details of a mortality event where Cyprinid herpes virus-2 (CyHV-2) was detected in association with multidrug-resistant Aeromonas hydrophila infection in goldfish, Carassius auratus, from commercial farms. The goldfish exhibited large scale haemorrhages on the body, fins and gills, lepidorthosis, necrosed gills, protruded anus and shrunken eyes. White nodular necrotic foci in spleen and kidneys were noticed, along with necrosis and fusion of gill lamellae. Transmission electron microscopy of affected tissues revealed the presence of mature virus particles. Involvement of CyHV-2 was confirmed by PCR, sequencing and observed cytopathic effect in koi carp fin cell line along with experimental infection study. A bacterium isolated from the internal organs of affected fish was found to be pathogenic Aeromonas hydrophila having resistance to more than 10 classes of antibiotics. We postulate that CyHV-2 was the primary etiological agent responsible for this outbreak with secondary infection by A. hydrophila. The experimental infection trials in Labeo rohita and koi carp by intraperitoneal challenge with CyHV-2 tissue homogenates failed to reproduce the disease in those co-cultured fish species. This is the first report of a viral disease outbreak in organised earthen ornamental fish farms in India and bears further investigation.
authors.affiliation: ICAR-Central Institute of Freshwater Aquaculture, Kausalyaganga, Bhubaneswar 751 002, India. Electronic address: pksahoo1@hotmail.com.
authors.forename: P K
authors.initials: PK
authors.lastname: Sahoo
authors.affiliation: Peninsular and Marine Fish Genetic Resources Centre of ICAR-National Bureau of Fish Genetic Resources, CMFRI Campus, Ernakulum North PO, Kochi 682 018, India.
authors.forename: T Raja
authors.initials: TR
authors.lastname: Swaminathan
authors.affiliation: Faculty of Fishery Sciences, West Bengal University of Animal and Fishery Sciences, Chakgaria, Kolkata 700 094, India.
authors.forename: Thangapalam Jawahar
authors.initials: TJ
authors.lastname: Abraham
authors.affiliation: Peninsular and Marine Fish Genetic Resources Centre of ICAR-National Bureau of Fish Genetic Resources, CMFRI Campus, Ernakulum North PO, Kochi 682 018, India.
authors.forename: Raj
authors.initials: R
authors.lastname: Kumar
authors.affiliation: ICAR-Central Institute of Freshwater Aquaculture, Kausalyaganga, Bhubaneswar 751 002, India.
authors.forename: S
authors.initials: S
authors.lastname: Pattanayak
authors.affiliation: ICAR-Central Institute of Freshwater Aquaculture, Kausalyaganga, Bhubaneswar 751 002, India.
authors.forename: A
authors.initials: A
authors.lastname: Mohapatra
authors.affiliation: ICAR-Central Institute of Freshwater Aquaculture, Kausalyaganga, Bhubaneswar 751 002, India.
authors.forename: S S
authors.initials: SS
authors.lastname: Rath
authors.affiliation: Faculty of Fishery Sciences, West Bengal University of Animal and Fishery Sciences, Chakgaria, Kolkata 700 094, India.
authors.forename: Avijit
authors.initials: A
authors.lastname: Patra
authors.affiliation: Faculty of Fishery Sciences, West Bengal University of Animal and Fishery Sciences, Chakgaria, Kolkata 700 094, India.
authors.forename: Harresh
authors.initials: H
authors.lastname: Adikesavalu
authors.affiliation: ICAR-National Bureau of Fish Genetic Resources, Canal Ring Road, Dilkusha, Lucknow 226 002, India.
authors.forename: Neeraj
authors.initials: N
authors.lastname: Sood
authors.affiliation: ICAR-National Bureau of Fish Genetic Resources, Canal Ring Road, Dilkusha, Lucknow 226 002, India.
authors.forename: P K
authors.initials: PK
authors.lastname: Pradhan
authors.affiliation: ICAR-Central Institute of Freshwater Aquaculture, Kausalyaganga, Bhubaneswar 751 002, India.
authors.forename: B K
authors.initials: BK
authors.lastname: Das
authors.affiliation: ICAR-Central Institute of Freshwater Aquaculture, Kausalyaganga, Bhubaneswar 751 002, India.
authors.forename: P
authors.initials: P
authors.lastname: Jayasankar
authors.affiliation: ICAR-National Bureau of Fish Genetic Resources, Canal Ring Road, Dilkusha, Lucknow 226 002, India.
authors.forename: J K
authors.initials: JK
authors.lastname: Jena
mesh_terms: D016980:Aeromonas hydrophila / Q000472:pathogenicity*; D000818:Animals; D017756:Aquaculture; D004196:Disease Outbreaks; D005393:Fish Diseases / Q000382:microbiology* / Q000473:pathology / Q000821:virology*; D006054:Goldfish / Q000821:virology*; D016905:Gram-Negative Bacterial Infections / Q000473:pathology*; D006566:Herpesviridae Infections / Q000473:pathology*; D007194:India; D007497:Iridoviridae / Q000472:pathogenicity*
keywords: Aeromonas hydrophila; Carassius auratus; Cyprinid herpesvirus-2; Emerging pathogen; Labeo rohita; Multidrug-resistance