Testimonial of a Veterinarian
In the past, cross-protection between different strains of PRRS has been sporadic and unpredictable. Protection when re-exposed to the same homogeneous virus is more predictable.
I did a series of trials involving pregnant sows, and the results demonstrated partial to full protection when challenged with a wild type PRRS virus. These sows had a history of prior field PRRS virus exposure and multiple doses of killed MJPRRS® vaccine. The challenge PRRS viruses were at least 8% different from what the sows were exposed to previously. Additionally, each challenge virus used had previously been associated with severe clinical disease in non-related herds.
Preliminary data is positive regarding this new MJPRRS vaccine. Additional trials are planned to confirm these findings. For a more complete summary of these trial results, refer to poster/abstract entitled "Protection against heterologous PRRSV challenge in pregnant sows immunized with multivalent PRRS vaccine" (1).
Mark Wagner, D.V.M.
Fairmont Vet Clinic
1. Wagner M., et al. Protection against heterologous PRRSV challenge in pregnant sows immunized with multivalent PRRSV vaccines. In: International PRRS Symposium, 2005 Dec. 2-3; St. Louis, MO.