This preclinical study tested a new vaccine approach in calves. The researchers used an intranasal immunization with a cocktail of recombinant BPI3VcmutBVDV viruses. They compared this new method to a standard commercial vaccine.
The results showed that the new vaccine elicited stronger serum antibodies and higher virus-neutralizing titers against both BVDV-1 and BVDV-2 viruses. Specifically, immune responses against several virus strains were significantly higher than those seen with the commercial vaccine.
When calves were challenged with the virus, those receiving the new vaccine showed steady weight gain, fewer gross lesions, lower viremia, and a smaller drop in lymphocyte counts. No adverse events or safety concerns were reported in this preclinical setting.
Readers should note this is a preclinical study, meaning it was done in animals before any human testing. The findings support further development of this live-attenuated vector for broader BVDV vaccines, but they do not yet change current human medical practice.