A recent affidavit from Canada's deputy chief veterinarian reveals that ostriches at a British Columbia farm are infected with a more lethal strain of avian influenza. Dr. Cathy Furness, with the Canadian Food Inspection Agency (CFIA), stated that further analysis of samples from the birds indicated a "novel reassortment" of the virus that has increased its pathogenicity. This strain is considered one of the most virulent tested at Canada's National Microbiology Laboratory, with even low doses proving fatal to mice within days.

The affidavit was submitted to the Federal Court of Appeal, where the CFIA is contesting a stay that would delay the culling of approximately 400 ostriches. The farm's owners argue that their flock is healthy and has developed "herd immunity" since the CFIA ordered the cull on December 31, following an outbreak that resulted in the death of 69 birds.

Furness's filing comes after the court granted the farm an interim stay, allowing them to seek a hearing at the Supreme Court of Canada. She noted that the new findings "increase the potential animal and human health risks associated with the ongoing delay" and the need for decontamination of affected areas.

The affidavit also highlights that ostriches can shed significant amounts of the avian influenza virus without showing symptoms. "Infected ostriches may still be shedding virus through their urine, feces, and respiratory secretions, despite appearing healthy. This is referred to as 'silent shedding'," the document states.

Universal Ostrich Farms has called for testing to confirm whether the birds are infected with the H5N1 strain. However, Furness indicated that the CFIA cannot determine the likelihood of infection or reinfection due to gaps in scientific knowledge about the duration of immunity in ostriches and the extent of the original outbreak.

The affidavit asserts that the criteria for a cull were met on December 31, 2024, and that the policy does not allow for additional testing. Furness emphasized that testing would only provide evidence of current risk and would not address the potential for reinfection or the risks posed by a contaminated environment.

The CFIA's risk assessment is also influenced by the farm owners' alleged failure to comply with quarantine regulations. Avian influenza viruses can persist in fresh water and on surfaces for extended periods, potentially leading to ongoing sources of infection.

Despite the challenges, Universal Ostrich Farms maintains that the birds should be spared due to their scientific value and lack of threat. The farm has faced setbacks in both Federal Court and the Federal Court of Appeal but continues to pursue legal avenues, including a recent request for another stay on the cull order. The Appeal Court granted an interim stay on September 6, allowing the CFIA to prepare for the cull while the case is under review.