The turkeys and chickens that haven't died from the disease will be euthanized — a total of about 35,000 birds.
Canada's chief veterinary officer, Harpreet Kochhar, says agencies are looking for any sign the virus has moved beyond the four farms in the Fraser Valley east of Vancouver.
Test results Thursday identified the flu strain as H5N2. The Canadian Food Inspection Agency says it's the same variety as three previous outbreaks in Canada.
This outbreak began earlier this week at a turkey farm in Abbotsford and a chicken farm in Chilliwack. Two additional farms were quarantined because they received birds from the Chilliwack farm.
There are no reports of the disease being transmitted to humans.