Marker vaccine

Marker vaccines allow the serological differentiation between vaccinated and infected animals.

General properties of a marker vaccine

The differentiation of vaccinated and infected animals is based on the absence of one or more proteins in the vaccine that are present in the wild type micro-organism. The use of companion tests that detect antibodies against the protein(s) lacking in the vaccine strain can detect infected individuals in vaccinated populations. Infection in a vaccinated herd can thus be monitored.