A novel herpes-like virus inducing branchial lesions in a tiger shark
18 November 2021
A novel herpes-like virus inducing branchial lesions in a tiger shark ( Galeocerdo cuvier)
Abigail R Armwood, Justin M Stilwell, Terry Fei Fan Ng, Tonya M Clauss, John H Leary, Doug Mader, Alvin C Camus
ABSTRACT:
A juvenile, male tiger shark (Galeocerdo cuvier) developed illness after capture in Florida waters and was euthanized. Gross lesions included mild skin abrasions, hepatic atrophy, and coelomic fluid. Histologically, gills contained multifocal lamellar epithelial cell necrosis and thromboses. Scattered gill and esophageal epithelial cells had large, basophilic, intracytoplasmic, and intranuclear inclusions. Ultrastructurally, lamellar epithelial cells contained arrays of intracytoplasmic viral particles and scattered intranuclear nucleocapsids. Capsulated virions were 148 ± 11 nm with an 84 ± 8 nm icosahedral nucleocapsid and an electron-dense core. Next-generation sequencing, quantitative polymerase chain reaction, and in situ hybridization performed on formalin-fixed tissue confirmed a herpes-like viral infection. The viral polymerase shared 24% to 31% protein homology with other alloherpesviruses of fish, indicating a divergent virus. This report documents the pathologic findings associated with a molecularly confirmed novel herpes-like virus in an elasmobranch.
Vet Pathol. DOI: 10.1177/03009858211052662