Canadian pork producers are one step closer to having a powerful new tool in the fight against porcine epidemic diarrhea.
A vaccine developed by the Vaccine and Infectious Disease Organization-International Vaccine Centre, also known as VIDO-InterVac, at the University of Saskatchewan has entered its final phase of testing.
But while the vaccine is a much needed firewall for Prairie pork producers, Andrew Dickson of the Manitoba Pork Council cautions the vaccine won’t be a panacea for preventing the virus that causes the disease.
“Our members are very excited at the possibility of having a vaccine that will protect our herd from this disease,” Dickson said. “But that doesn’t mean we can relax our biosecurity. What it does is provide an additional line of defence, it doesn’t mean we can give up worrying about border crossings and trailers or stop worrying about assembly yards.”
Making sure that any vaccine that becomes available is effective is also important, he said, but added that even an efficacy rate of 80 or 90 per cent would have a big impact when it comes to controlling the spread of the disease.
“With our herd being essentially naive, this offers a significant amount of protection, even with say 10 per cent of pigs left unprotected,” Dickson said. “You need a big pool of animals for this to spread, so the more pigs that are vaccinated successfully, the harder it will be for the disease to spread.”
Using its new containment Level 3 facility, VIDO-InterVac was able to successfully demonstrate that up to 100 per cent protection could be provided using the vaccine, which relies on the spike protein, something researchers have long been convinced is what allows the virus to initiate the infection of the host pig.
VIDO-InterVac’s research director, Volker Gerdts, said that about 700 sows in three commercial operations have now been vaccinated and brought back to the research centre. Piglets from these sows have now been infected with the virus to test the vaccine’s efficacy rate.
“So we don’t have data completed or analyzed there yet, that is still going on, so we don’t know what (the efficacy rate) is in the field,” Gerdts said. “But we will.”
The vaccine was also used in three Manitoba hog barns during recent porcine epidemic diarrhea outbreaks.
“They asked us if they could use the vaccine in their outbreak, and we got permission from CFIA (Canadian Food Inspection Agency) to use it in those herds,” said the researcher. Blood samples from animals in those barns have yet to be tested, but Gerdts said the producer in that case felt the vaccine did give replacement gilts some level of protection.
During lab trials and tests in commercial sow barns, between 80 and 90 per cent of neonatal piglets were given protection from the virus after sows were vaccinated four to five weeks before farrowing, and then vaccinated again two weeks prior to farrowing. Immunity is passed from the sow to the piglets via her colostrum.
While complex, Gerdts said the vaccine has come together quickly.
“We put a large team of researchers on it and we pursued different strategies, different types of vaccines and so on,” he said. “Commercial production could start very soon, but it’s really a question of how quickly can they get it registered in Canada so that producers can use it… I think everyone is interested in getting it out as quickly as possible.”
Commercialization of this vaccine is being fast tracked by the European pharmaceutical company Huvepharma.
“This is an exciting partnership with a world-class organization,” said Boris Gavrilov, senior scientist for biologics development at Huvepharma. “Our goal is to have the vaccine available for commercial use as soon as possible to help stop producer losses.”