Replicon Particle Porcine Reproductive and Respiratory Syndrome Virus Vaccine Provides Partial Protection from Challenge

Replicon particles (RPs) expressing the GP5 and Matrix structural proteins of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) were created and compared to inactivated PRRSV in a challenge study. Pigs that received the RP vaccine had lower live virus titers and showed lower IDEXX ELISA values following challenge when compared to other groups. These results show that the RP vaccine provided partial protection against challenge with virulent PRRSV. Also, the RP vaccine allows for differentiation between vaccinated and naturally infected animals.