The porcine reproductive and respiratory syndrome quandary. Part I: Fact versus speculationk

Over the years, many of our efforts have focused on the development of PRRS vaccines that we hoped would be just as effective as those used to help prevent several other economically important viral diseases of swine (eg, swine fever, pseudorabies, parvovirus-induced reproductive failure, and swine influenza), but unfortunately, this has not been the case. While attenuated-live-virus PRRS vaccines do provide clinical protection under many circumstances, and in such cases are clearly cost effective, the level of protection is too often less than what we have come to expect from past experiences with many other attenuated-live-virus vaccines.