SHIC Reports Increased PRRS and PED Activity but Decreased Influenza A Activity

The Swine Health Information Center reports increased Porcine Reproductive and Respiratory Syndrome and Porcine Epidemic Diarrhea case positivity during November while Influenza A case positivity fell to its lowest level since 2015.As part of its December eNewsletter the Swine Health Information Center has released its monthly domestic and global swine disease monitoring reports.

SHIC Associate Director Dr. Lisa Becton says we saw both PRRS and PED increase over the past month while influenza A declined.

Quote-Dr. Lisa Becton-Swine Health Information Center:

For this month we saw an increase in PRRS case positivity to 48.5 percent in the wean to finish age category and this was unfortunately the highest seen since 2018.For PED case positivity, sows saw an increase of 6.5  percent and wean to finish at 17.4 percent, which is above predicted levels for this time of year. We do know that PRRS and PED case positivity does increase during the winter months for a variety of different reasons.

It may indicate there is an increased level of virus circulating in certain areas of the country and within the industry.And, because of some potential instability in sow farms, there may be seen a leakage of PRRS virus out into wean to finish.Also, we normally do see an increase in activity over the last 30 days, as reported by the advisory group, and that includes both new and recirculation of endemic strains of the virus.For PED it is also typical to see increased case positivity this time of year and that could be associated with increased manure pumping that occurred earlier this fall.

Dr. Becton notes influenza case positivity in sows this fall decreased to its lowest since 2015.She says the reason is unknown but there are typically more intervention strategies performed on sow farms, which may include vaccination and other strategies to help reduce viral transition to help moderate influenza in that population and  there could just be less overall influenza activity.

SHIC's domestic and global swine disease monitoring reports can be accessed at swinehealth.org.