Porcine Reproductive and Respiratory Syndrome or PRRS was first discovered in 1987 and has spread worldwide.

The viral infection is characterized reproductive problems in the breeding herd including poor conception rates and abortion and respiratory problems which cause poor performance or death in the nursery and finishing phases.

Dr. Tim Loula, with the Swine Vet Center, notes PRRS can be transmitted through several vectors including unclean trucks, insects or the introduction of new gilts or boars and, while modern biosecurity measures have controlled those sources, aerosol transmission remains a problem.

Dr. Tim Loula-Swine Vet Center

If you're in an area of very low pig density you can have a negative herd and stay negative.

If you're in a very high densely populated area for numbers of pigs in the area, number of farms, number of different producers you are at high risk to get re-infected.

If you're in a decent low density hog area you should seriously look at eradicating and we need to be more efficient.

We have high grain prices and will for awhile so we have to be more efficient.

If you're in a high pig dense area then you're going to need to stabilize the PRRS and probably maintain a PRRS positive status but stabilize.

That can be done with either commercial vaccine or with the use of natural exposure via serum etceteras.

So there's two primary ways that we end with herds either low pig dense areas eradicate it or high pig dense area we stabilize.

Dr. Loula notes the success of a ten year program to eradicate pseudorabies and he believes the eradication of PRRS is possible.

He admits one of the challenges is that the PRRS virus is so adaptable.

He notes over seven thousand strains, many of which are not affected by existing vaccines, have been identified.