Salat et al.
Efficacy and immunogenicity of a veterinary vaccine candidate against tick-borne encephalitis in dogs
Vaccine. 2023;41(42):6150-6155. doi:10.1016/j.vaccine.2023.09.019
Canine TBE virus infections are usually asymptomatic. However, dogs can suffer from severe TBE (mostly monophasic), and TBE virus infections can even be fatal in dogs (see also Snapshot week 46/2021 about the experimental infection of dogs). A canine TBE vaccine candidate (produced in BHK-21 C13 SUSP suspension cell line) has been developed based on inactivated whole virus antigen (strain Hypr). This vaccine contains aluminum hydroxide and thiomersal.
Vaccination of mice yielded protection against challenge with TBE virus. Dogs were vaccinated three times three weeks apart. No local or systemic reactions were observed after vaccine administration.
Challenge with strain 9001 was done three weeks after the last vaccine injection. No viremia was detected in vaccinated dogs, while TBE virus was detected in the non-vaccinated control group. Serum TBE IgG was measured in all vaccinated animals (median 149 VIEU/ml) after the third vaccination, and TBE IgG ELISA concentrations increased after challenge to 421 VIEU/ml one week after challenge and the ELISA IgG values were confirmed by neutralization assay. Sera collected from vaccinated dogs were shown to have neutralizing activity, while control sera did not neutralize TBE virus.
These data indicate the safety, immunogenicity and efficacy of the newly developed TBE vaccine in mice and/or dogs, and therefore it could serve as a reliable protective measure against TBE in dogs in the future.