Hit by an unprecedented avian flu pandemic, the United States is seriously considering launching a massive vaccination campaign for farmed birds. What about in Canada? Update with Dr. Manon Racicot, veterinary epidemiologist from the Canadian Food Inspection Agency.

Recently, the New York Times revealed that the Biden administration was thinking in high places about the possibility of setting up a vaccination campaign for farm birds. The Department of Agriculture has already begun testing vaccine prototypes and initiated discussions with the poultry industry about the feasibility of large-scale vaccination. In the United States, laying hens have been particularly affected by the crisis, to the point that the price of eggs has jumped 70% in one year. “The Americans, their problem is that they have such huge farms that when the virus comes in, it’s catastrophic. […] They have farms with millions of layers. We don’t have this kind of breeding in Canada, “said Dr. Racicot in an interview with La Presse.

In Quebec, 10 backyards are currently dealing with active infections. They are located in three RCMs: Rouville, Beauharnois-Salaberry and Haut-Saint-Laurent. The very first case detected in a farmed bird in Quebec history occurred in April 2022. Since then, 32 “commercial” or “artisanal” farms have experienced an outbreak in the province. Approximately 609,000 farmed birds have been “affected” in Quebec and 7.2 million in Canada. “Affected” birds either died of the disease or were euthanized on the spot to curb the spread of the virus within the flock or nearby farms and buildings. This highly virulent new episode of H5N1 avian influenza began in December 2021 when the virus was detected in a wild bird in Newfoundland.

“As of today, there is no available and effective vaccine against what is currently circulating that is manageable in terms of administration. We must continue to follow the clinical trials that are underway, “replies Dr. Racicot from the outset. On the other hand, Canada is closely following the evolution of the file. Although interesting, vaccination poses many challenges. “In Canada, we have several reassortments of the virus. That is, we have H5N1, but there are different genes from the Eurasian lineage and the North American lineage [in different regions]. This means that it takes a vaccine that will be effective for the whole country, ”said Ms. Racicot.

The second big challenge with vaccinating farm birds is the mode of administration, says Racicot. “Currently, the vaccines that are available in poultry and not yet authorized in Canada, those that are for example used in Mexico or China, are mainly injectable. So it often takes a first dose at the hatchery and a second dose at the farm. There is a vaccine administration challenge in itself, because injecting millions, if not billions of birds, is practically unsustainable,” she said. In an era of labor shortages in the agricultural sector, administering the vaccine in the water or food of the birds could be an attractive option.

Currently, Canada proves the absence of avian influenza in birds that are exported by demonstrating that they have no antibodies to the disease. “So there, if we vaccinate, we will not be able to do this demonstration,” explains Dr. Racicot. For now, she adds, the majority of trading partners do not accept birds from vaccinating countries. “It’s going to be a paradigm shift. We will have to have deep discussions with our commercial partners if we decide to vaccinate. We will have to find a way to prove that we are absent from the disease or that the disease is [under control]. »

With good weather, migratory birds carrying the bird flu virus return. If cases of avian flu have spread at such lightning speed, it is primarily because the virus has never been so present in wild species. Ducks, geese, barnacles, sandpipers, gannets, common eiders, guillemots, razorbills, crows, ravens, snowy owls, eagle-owls, gulls: dozens of species of wild birds have been infected. “There is a very large geographic range and a very large variability in the species currently affected in wild birds,” Racicot points out.

One of the vectors of spread to farms would come from the secretions or droppings of wild birds that would inadvertently end up on agricultural equipment or the soles of workers. Cases on farms are therefore likely to skyrocket in the coming months. The main protective measure for breeders is to follow a strict biosecurity protocol; changing boots before entering the coop is particularly important. “The key message to producers is biosecurity,” says Racicot.