Abstract
A modified passive cutaneous anaphylaxis test and an ELISA were used to identify IgE in calves vaccinated (sensitized) with chlorine dioxide- inactivated bluetongue virus (BTV) and in calves inoculated with infectious BTV. The levels of IgE were greatest in the vaccinated calves after challenge with infectious virus, which correlated with development of clinically apparent dermatitis and stomatitis. These findings suggest that some aspects of clinical bluetongue disease in cattle may have an immunopathological mechanism mediated by IgE (type I hypersensitivity).