Mink were inoculated with two different Canine distemper viruses (CDV) - a Danish (DK91) virus strain and an American (Snyder Hill) virus strain. DK91 represents a circulating European wildtype genotype, while the Snyder Hill strain represents the American genotypes isolated before 1960. Clinical and paraclinical investigations of the mink were performed after inoculation. The wildtype CDVs investigated provoked marked virulence differences. The Danish wildtype showed a mildly virulent course in our natural host model, in contrast to the acute, severe disease outcome in the Snyder Hill challenged mink.
Furthermore, we investigated if DNA vaccine consisting of the genes from vaccine strains induced cross-protection against circulating European CDV. Our results indicate that DNA vaccine-induced immunity protected the mink against disease development. Further work on DNA vaccines against circulating wildtype CDVs could lead to new and safer strategies to control and to prevent distemper.