First report of a new alphaherpesvirus in a freshwater turtle (Pseudemys concinna concinna) kept in Germany

Herpesviruses represent important pathogenic agents in zoological chelonian collections. Infections in tortoises are actually most commonly associated with necrotizing lesions in the upper digestive tract. Herpesvirus infections in sea turtles are most commonly associated with fibropapillomatosis, although other disease complexes caused by other herpesviruses have been described. Herpesviruses are known to cause latent infections and may be reactivated upon various endogenous or exogenous stimuli resulting in acute and sometimes fatal disease. The present description represents the first report about a new alphaherpesvirus found in a fresh water turtle (Pseudemys concinna concinna). The animal died suddenly without showing clinical signs. Macroscopically, no lesions typically associated with a herpesvirus infection were found. Light microscopic examination showed hepatic lipidosis and countless numbers of intranuclear inclusion bodies in hepatocytes as the only significant light microscopic lesion. Transmission electron microscopy revealed typical herpesvirus particles in the nucleus of hepatocytes. To further substantiate these observations a molecular identification using PCR followed by sequencing of the obtained fragments was performed. Phylogenetic analysis indicated a new alphaherpesvirus called Emydid herpesvirus 1.