The lake sturgeon (Acipenser fulvescens; LST) is the only sturgeon species in the Great Lakes (GL), where populations are estimated to be <1% of historical abundances. Resultantly, substantial resources are being devoted to the hatchery propagation of LST. Concurrently, more is being uncovered regarding viral diseases that affect sturgeons (e.g. Frog virus 3 [FV3], Nucleocytoplasmic Large DNA viruses [NCLDVs], Acipenserid herpesviruses). To investigate the presence of these viruses, I collected wild adult and hatchery reared juvenile GL-LST (Lake Erie, Huron, Michigan, and Superior watersheds) and utilized specialized/specific molecular and in vitro diagnostics. Although FV3 and NCLDVs were not detected in sampled GL-LST, I successfully detected and, for the first time, isolated a herpesvirus (Family Alloherpesviridae) from adult GL-LST that, based on genomic analyses, appears distinct from known alloherpesviruses. To assess virulence of this virus (proposed name of lake sturgeon herpesvirus 2, LSHV-2), juvenile GL-LST were immersed in a viral suspension. Within 10 days, disease signs developed in virus-exposed LST, soon progressing to mortality (33% cumulative mortality), where LSHV-2 was re-isolated from representative skin lesions. Next, the efficacy of three disinfectants (Perox-Aid℗ʼ, VirkonTM-Aquatic, and Ovadine℗ʼ) against LSHV-2 was assessed in vitro, where all three substantially decreased viral titers to varying degrees, marking promising means of prevention/control. Whether LSHV-2 has or is contributing to reduced LST abundance in the GL remains to be determined, but my findings provide a foundation to further study and combat this newly uncovered sturgeon-pathogenic virus.
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