Diva vaccines that reduce virus transmission

This brief review deals with the effect of diva (Differentiating Infected f rom VAccinated individuals) vaccines (also termed marl;er vaccines) on tran smission of herpesviruses and pestiviruses in swine and cattle. Pseudorabie s and bovine herpesvirus 1 diva vaccines have been demonstrated to reduce t ransmission of wild-type virus in populations of pigs and cattle in the lab oratory as well as in the field. A subunit diva vaccine based on the immuno dominant E2 protein of classical swine fever virus that is expressed in the baculovirus system may reduce transmission of wild-type virus among pigs a nd also transmission from mother to foetuses. A similar diva vaccine agains t bovine virus diarrhoea infections protected sheep against transplacental transmission of antigenically homologous wild-type virus. Diva vaccines alo ng with their companion diagnostic tests can play a role in control of infe ctions: ultimately leading to eradication of viruses, (C) 1999 Elsevier Sci ence B.V. All rights reserved.