Leman Swine Conference: Controlling PEDV with bioexclusion, biocontainment and biomanagement

Biosecurity is made up of three components: bioexclusion, biocontainment and biomanagement, according to Karine Talbot, DVM, HyLife Ltd, Canada.

• Bioexclusion is the most well-known: external biosecurity, all the steps taken to prevent infectious diseases from entering the herd.
• Biocontainment is all the steps taken to prevent infectious diseases from getting out of an infected barn and spreading to others.
• Biomanagement is internal biosecurity. It is all the steps taken to prevent (or minimize) infectious diseases from spreading from infected pigs to non-infected pigs within the same barn.

In the fight against the porcine epidemic diarrhea virus (PEDV), all three biosecurity components are needed. PEDV is a different beast when it comes to biosecurity; it is extremely infectious and contagious, and very little is needed to infect a naive barn. If strong bioexclusion and biocontainment are not in place ahead of an outbreak, PEDV can spread like wildfire, Talbot said during the 2023 Leman Swine Conference.

The level of bioexclusion implemented is often based on a risk versus impact approach per barn. Boar studs, multipliers and sow barns usually have a higher level of bioexclusion protocols to protect them from diseases, she said.

But in a pig-dense area, does it still make sense to have low biosecurity levels in certain herds? If a finishing barn near a large sow barn breaks with PEDV due to poor biosecurity protocols, it will increase the risk for that sow barn, no matter how good the bioexclusion protocols are, Talbot emphasized.

To control diseases like PEDV, every barn must have good biosecurity measures in place. Biocontainment is also key to protecting others against PEDV. Everything coming out of the herd becomes a potential risk to spread PEDV to others: people, tools and equipment, trucks and trailers, but also pigs.

Biomanagement
Talbot asked some difficult questions: 

• Where are these PEDV positive pigs going to be placed? 
• Close to which barn? 
• Whose barn?

With PEDV (and many other diseases), it is never a “single herd problem,” she said. One producers’ disease management decision will impact the neighbors around them. Where the PEDV positive pigs will be moved to affects the swine industry in general. There are cross-contamination risks for feed mills, livestock trailers, cull sow assembly yards and slaughter plants, she added.

Other key elements of a complete biosecurity program are health monitoring (surveillance) and sharing of information. To have a chance in the fight against PEDV, it is important to know which herds are positive (and not every case is obvious) by performing routine surveillance. That information must be shared between veterinarians and producers in the area. As the popular saying goes: “knowing is half the battle,” she said.

Biosecurity is more than just protecting a herd from what could come in (bioexclusion); what’s coming out (biocontainment) must also be considered. And to be successful in the fight against PEDV, both must be implemented in all types of herds (sow, nursery and finishing). It’s much easier to protect herds in an area where PEDV is not present.