U.S. pork producers are being advised to keep on top of the PRRS strains circulating in their barns in order to determine the best options for protecting their pigs.
The Swine Health Information Center's domestic swine disease surveillance report for December indicates the incidence of PRRS detection increased last month, propelled by the highest number of PRRS 1-4-4 L1C variant detections since its emergence in 2020.
Swine Health Information Center Associate Director Dr. Megan Niederwerder says detections increased in all age groups.
Clip-Dr. Megan Niederwerder-Swine Health Information Center:Click here to see more...
We are seeing this increase in the L1C variant and the states with the highest number of that variant virus detected were Iowa, Minnesota and Missouri.
We see this Lineage 1C variant increase throughout the Midwest.
This variant has been seen in grow finish and has been seen at an increased rate of lateral spread from grow finish site to grow finish site and then we've seen this increase in the spillover to sow farms in areas that are either swine dense or have a very high density with regards to the PRRS virus strain, this Lineage 1C strain.
One of the Advisory Committee's recommendations is that we have not seen this Lineage 1C variant in as high a levels in the states that are east of the Mississippi River.
So, thinking about that there are still locations in the U.S. and in other countries that have not seen this Lineage 1C variant, the Advisory Group's hope is that those states will remain negative and have the biosecurity practices in place to prevent entry because, as we've seen over the past two years, once it's introduced into in a state and to a region, it's been difficult top control and difficult to eliminate.