TY - JOUR T1 - Evaluation of the epidemiological importance of classical swine fever infected, E2 sub-unit marker vaccinated animals with RT-nPCR positive blood samples. JF - J Vet Med B Infect Dis Vet Public Health Y1 - 2005 A1 - Dewulf, J A1 - F. Koenen A1 - Ribbens, S A1 - Andy Haegeman A1 - Laevens, H A1 - de Kruif, A KW - Animals KW - Antibodies, Viral KW - Classical Swine Fever KW - Classical swine fever virus KW - Disease Transmission, Infectious KW - Female KW - Infectious Disease Transmission, Vertical KW - Male KW - Pregnancy KW - Reverse Transcriptase Polymerase Chain Reaction KW - Swine KW - Vaccination KW - Vaccines, Marker KW - Vaccines, Subunit KW - Viral Vaccines AB -

It has been demonstrated that pigs that have been double vaccinated with an E2 sub-unit marker vaccine and that are infected with classical swine fever virus (CSFV) through a natural contact infection may react positive in a CSFV detecting RT-nPCR test, whereas no virus could be isolated by using the conventional virus isolation (VI) technique. To evaluate whether these vaccinated and infected pigs may spread the virus, three experiments were set up. In the first, susceptible pigs were inoculated with serum originating from vaccinated RT-nPCR positive pigs. In the second, vaccinated RT-nPCR positive pigs were brought into contact with sentinel animals. In the third, vertical transmission was evaluated in RT-nPCR positive vaccinated pregnant gilts. In the first two experiments, no proof of virus transmission was found, whereas in the third vertical transmission was observed. The conclusion is that in vaccinated pigs that are positive in RT-nPCR but negative in VI, the level of circulating virus is probably not high enough for horizontal transmission, whereas vertical transmission of the virus is possible.

VL - 52 CP - 9 U1 - http://www.ncbi.nlm.nih.gov/pubmed/16283914?dopt=Abstract M3 - 10.1111/j.1439-0450.2005.00884.x ER -