4 poultry farms in southwestern Ontario hit with avian flu resulting in 63k birds culled so far

The Canadian Food Inspection Agency (CFIA) says it has identified additional outbreaks of avian influenza in the Strathroy, Ont. area, bringing the total number declared in the last two weeks to four.

The most recent outbreak was uncovered Friday after the highly pathogenic avian influenza, or HPAI, was confirmed at a commercial poultry farm in the region, the CFIA said on its website.

It's not clear yet how many birds may be affected by this most recent outbreak.

It comes two days after an outbreak was declared on Wednesday, affecting at least 15,469 turkeys, the CFIA said in a statement.

The CFIA did not provide the name or exact location of the affected farm in that outbreak, but said it was about five kilometres from the two farms impacted in outbreaks last week and earlier this week.

Those two earlier outbreaks affected roughly 32,000 turkeys and 15,600 turkeys, respectively, according to the CFIA, bringing the total number of birds impacted to at least 63,069, a number that will increase with Friday's outbreak.

"All affected birds will be humanely depopulated and disposed of in accordance with all necessary provincial requirements," the CFIA said Friday, adding no single source had been determined.

The four outbreaks are Ontario's only active avian influenza outbreaks.

Two primary control zones, PCZ-302 and PCZ-308, have been established by the CFIA for the four outbreaks to prevent spread. Combined, they cover most of Strathroy-Caradoc, and parts of Adelaide Metcalfe, Chippewas of the Thames First Nation, Middlesex Centre and Southwest Middlesex.

Movements in, out, within or through the PCZ requires a permit in order to move birds, their products, and any by-products, the agency said. When it's determined the disease is no longer in the affected area, the PCZ may be revoked.

CBC News reached out to several poultry associations, but was directed to the Feather Board Command Centre (FBCC), which co-ordinates the Ontario poultry industry in response to disease risk.

"HPAI is not a food safety concern — it is a flock health issue. As such, we are taking this issue very seriously and are working with CFIA and our provincial boards to ensure the health of our birds," said Maggy Watson-Sparks, FBCC's general manager, in an emailed statement.

CFIA says many factors can contribute to the presence of avian flu in an area, including the migration of wild birds, with the risk for domestic poultry rising during migratory season.

The dominant strain circulating, H5N1, is highly infectious, and can spread rapidly among a flock of domestic birds, said Beth MacDougall-Shackleton, a Western University biology professor specializing in disease ecology in migratory birds.