Safety and efficacy of a thymidine kinase negative equine herpesvirus-1 vaccine in young horses.
A drug induced equine herpesvirus-1 (EHV-1) mutant lacking thymidine kinase inducing activity was developed and evaluated as a vaccine. The safety and effectiveness of the vaccine to protect against experimentally induced EHV-1 respiratory disease were evaluated in weanling horses free of EHV-1 neutralizing antibody. The vaccine was safe when administered either intramuscularly or intravenously, and EHV-1 was not shed intranasally during the 12 days following administration. Intranasal challenge with virulent EHV-1 was used to evaluate vaccine efficacy. Following challenge, there was a significantly (p less than 0.05) greater increase in peak body temperatures and duration of nasal virus shedding in the nonvaccinates, and a significant (p less than 0.05) increase in serum neutralizing antibody titers in the vaccinates.
Cornick
J
J
Large Animal Medicine and Surgery, Texas Veterinary Medical Diagnostic Laboratory, Texas A&M University, College Station 77843-4475.
Martens
J
J
Martens
R
R
Crandell
R
R
McConnell
S
S
Kit
S
S
D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis; D001831:Body Temperature; D004279:DNA, Viral / Q000032:analysis; D004587:Electrophoresis, Agar Gel; D004790:Enzyme Induction; D006564:Herpesviridae / Q000276:immunology*; D006566:Herpesviridae Infections / Q000517:prevention & control / Q000662:veterinary*; D004861:Herpesvirus 1, Equid / Q000201:enzymology / Q000235:genetics / Q000276:immunology*; D006734:Horse Diseases / Q000517:prevention & control*; D006736:Horses; D007958:Leukocyte Count / Q000662:veterinary; D009154:Mutation; D009504:Neutrophils; D015183:Restriction Mapping; D013937:Thymidine Kinase / Q000096:biosynthesis* / Q000235:genetics; D014611:Vaccination / Q000662:veterinary; D014765:Viral Vaccines / Q000276:immunology
D000914:Antibodies, Viral; D004279:DNA, Viral; D014765:Viral Vaccines; D013937:Thymidine Kinase