A professor with the University of Minnesota says the wide range of vectors through which PRRS can spread poses the biggest challenge for regional efforts to control the disease.
Porcine Reproductive and Respiratory Syndrome, a viral infection that causes reproductive problems in sows and respiratory disease in grower pigs, is the most costly disease in North America.
Dr. Bob Morrison, a professor of veterinary medicine with the University of Minnesota, says at last count 15 or 16 groups throughout North America had initiated regional PRRS elimination efforts.
As in most infections the pig or semen is the most common source of infection and so you worry about where your replacement animals are coming from or if let’s say you’re purchasing pigs, they’re mixing sources etceteras, pigs and semen is going to be the number one source.
After that it’s what sort of surfaces the virus might have come in contact with that might still have virus on it, in which case we worry about transportation for example.
If you’re transporting pigs that are infected and then the pigs leave at market and then you use that same truck to go and transport some other pigs to a farm then in all likelihood if the virus was on the truck those pigs, when they arrive at the farm, are going to be infected so we worry about trucks for example.
At farms we worry about boots or equipment or coveralls, all of those can have virus on it that has been shed from pigs.
The very fact that PRRS virus can be on all of these surfaces and in additional can go through the air makes regional elimination very difficult.
If you can get virus coming to your farm from a mile away or several kilometers away then that really complicates the elimination of the virus.
Dr. Morrison says most of the PRRS elimination efforts have started in the last year so it’s to early to gauge success.
He concedes, in very pig dense areas, regional elimination may not be appropriate because of the difficulty in keeping the disease from spreading between farms.
Source: Farmscape.Ca
