Isolation and characterization of an atypical Siberian sturgeon herpesvirus strain in Russia: novel North American Acipenserid herpesvirus 2 strain in Europe?

• Published in: Journal of Fish Diseases
• Main Authors: Doszpoly, A, Kalabekov, I M, Breyta, R, Shchelkunov, I S
• Other Authors: Országos Tudományos Kutatási Alapprogramok
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2017
• Subjects: Veterinary (miscellaneous); Aquatic Science; Siberian sturgeon
• Online Access: http://dx.doi.org/10.1111/jfd.12611; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fjfd.12611; https://onlinelibrary.wiley.com/doi/pdf/10.1111/jfd.12611

Abstract Siberian sturgeon herpesvirus (Sb SHV ) was isolated in Russia for the first time in 2006. Nine Sb SHV isolates were recovered from different fish hatcheries producing the same cytopathic effect in cell cultures, the same clinical signs and mortality kinetics in virus‐infected fish and the same virus neutralization pattern and shared identical nucleotide sequences. In 2011, a new isolate was recovered from juvenile sturgeon, which caused completely different cytopathic effect. That isolate was not readily neutralized by Siberian sturgeon hyperimmune antisera, and its DNA was not recognized by the routine PCR developed for Sb SHV detection. Molecular study of the novel isolate revealed that it was more closely related to North American Acipenserid herpesvirus 2 (Aci HV ‐2) isolates from white sturgeon, while the genome sequences of the former Sb SHV isolates showed high similarity to the Aci HV ‐2 isolated from shortnose sturgeon. While clinical signs and mortality caused by the novel isolate in infected Siberian sturgeon were similar to those of the formerly described Sb SHV isolates, the incubation period and mean time to death produced by the novel isolate were twice as long. The differences between the former isolates and the recent one suggest that a novel Sb SHV strain emerged in Europe and the molecular findings imply its North American origin.