Cyprinid herpesvirus 3 is a highly contagious pathogen, which causes fatal KHVd of ornamental and food carp species.1,2 When introduced into an aquaculture facility or ornamental collection, epizootics are devastating to koi (Cyprinus carpio koi) and impact breeders, dealers, hobbyists, pet retailers, and aquaculturists.3–5 Even with proper quarantine protocols and screening tests, CyHV3 can be introduced into aquatic systems as a result of latent or persistent low-level infections in koi, which can be reactivated by temperature stress.6–8 Exposure can also occur via contaminated water sources, where virus can persist for up to 3 months.9 Skin, rather than the gills, is the major portal of entry of the virus.10
Recently, a modified-live CyHV3 vaccine was tested in the United States to examine safety and efficacy for use in koi against KHVd.11 The vaccine was found to have a favorable safety profile, even when used at 10 times the recommended dose, and it provided immunity against CyHV3 following challenge exposure.11 The objective of the study reported here was to determine whether the modified-live CyHV3 vaccine provided protective immunity in koi against challenge exposure with a wild-type CyHV3 13 months after vaccination. Results could provide the koi industry with information to more effectively protect koi from the destructive effects of KHVd.
Cyprinid herpesvirus 3
Koi herpesvirus disease
Koi Enterprise, Sacramento, Calif.
KoVax Ltd, Jerusalem, Israel.
Silver Cup, Skretting USA, Tooele, Utah.
Western Chemical, Ferndale, Wash.
Arm and Hammer, Princeton, NJ.
DNeasy blood and tissue kit, QIAGEN, Germantown, Md.
StepOne, Applied Biosystems Inc, Foster City, Calif.
Promega, Madison, Wis.
SPSS statistics, version 19.0, IBM Corp, Armonk, NY.
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