Environmental testing helps pork producers focus their time and resources where it counts most, especially in preventing the spread of Porcine Epidemic Diarrhea (PED).
Dr. Lisa Becton, Associate Director of the Swine Health Information Center (SHIC), says producers are making progress on PED, but transport-related contamination remains a big issue.
“PED cases are down on farms across all age groups,” said Dr. Becton. “But when we look at vehicle and truck wash samples, the positivity rate stays high, around 17 percent.”
The SHIC’s July eNewsletter includes domestic and global swine disease monitoring reports. Dr. Becton says that the ability to detect the virus in environmental samples gives producers a competitive edge.
“Environmental testing gives us insight into where the virus lives,” she said. “It shows us if contamination is happening at truck washes, inside trailers, or at packing plants.”
That information enables staff to pinpoint problem areas.
“Not all farms have PED,” says Dr. Becton. “If a site tests clean, we don’t have to throw time and money at it. We can focus on where the risk is real.”
Dr. Becton says this targeted approach saves time and supports better bio-security
“Everyone knows transport is a weak spot,” she said. “We simply don’t have enough wash bays, trailers, or time to clean every unit 100 percent, every time. But with testing, we can identify the high-risk areas and respond.”
PED isn’t the only concern. The SHIC report shows Porcine Reproductive and Respiratory Syndrome (PRRS) remains a major issue, especially with the emergence of a new variant.
“We just detected PRRS lineage 1C.2 in North Carolina,” says Dr. Becton. “That’s the first time we’ve seen that variant there. It’s a nasty one that’s already caused damage in the US Midwest.”
She says this detection sends a clear signal.
“Producers need to double down on keeping PRRS out,” she said. “Focus on bio-exclusion to prevent entry—and if it’s already in, work on bio-containment to keep it from spreading.”
Other states with high PRRS case numbers include Iowa, Minnesota, South Dakota, and Indiana. The average case positivity in wean-to-finish pigs sits around 40 percent.
“That’s high for June,” says Dr. Becton. “We usually expect those numbers in colder months, not in summer.”
Porcine Delta Coronavirus (PDCoV) also shows increased activity in Missouri, Indiana, Ohio, and North Carolina. Meanwhile, PCV2 cases rose in grow-finish pigs, and PCV3 appeared more often in sow operations. Dr. Becton says the jump in Mycoplasma detection ties to better surveillance, not necessarily more infections.

“Some of the increase is simply because we’re sampling more,” she said.
Globally, African Swine Fever (ASF) continues to move. A new case of wild boar in Germany raises fresh concern.
“We found genetic links between that wild boar case and strains in southern Italy,” Dr. Becton explains. “It popped up 75 miles from the last known positive case. That’s not nothing.”
She believes human movement may play a role.
“People may unknowingly move the virus, especially during vacation season,” she said. “It’s vital to disinfect your boots and clothes if you’ve been abroad and avoid bringing any meat products back home.”
Vietnam recently shipped its first doses of an ASF vaccine to Indonesia. The vaccine, produced by AVAC Vietnam, has undergone extensive testing over several years.
“This is promising,” says Dr. Becton. “Countries where ASF is endemic now have one more tool to slow the disease.”
She says the AVAC vaccine reduces clinical signs and helps limit the spread of the disease.
“Three ASF vaccines are now commercially available—AVAC, Nevetco, and Debaco,” she said. “Several others are in clinical or experimental trials.”
She stresses that safety must come first.
“These vaccines must trigger an immune response, match field strains, and avoid shedding live virus,” she said. “They also need to be safe for animals and the environment.”
Projects like Vax4ASF, which involve 17 international organizations, are still in the early stages of development.
Dr. Becton encourages pork producers to stay current.
“Our SHIC newsletter gives producers free access to all this information,” she said. “Whether you’re fighting PED, PRRS, or watching for ASF, the tools are improving—but you still need to use them wisely.”
Producers can access the latest swine health updates at swinehealth.org
“We’re here to help producers make informed decisions,” says Dr. Becton. “And environmental testing is one of the best tools we have right now.” •
— By Harry Siemens