The Canadian Food Inspection Agency says bird flu has been found on a third farm in southern Ontario.

The agency says the highly pathogenic H5N1 strain of avian flu was found in a poultry flock in Woolwich, Ont. on Wednesday.

This follows the confirmation of the virus in a poultry flock on Monday in Zorra, Ont., outside London, Ont.

Bird flu was first detected on an Ontario farm on Sunday, in another poultry flock near Guelph, Ont.

The CFIA says it has implemented control zones and is helping nearby farms increase their biosecurity.

Industry leaders say farms are on high alert.

“All producers are very aware of this,” Brian Ricker, chairman of the Turkey Farmers of Ontario told CTV Kitchener on Tuesday. “Everyone will be very careful about who goes on their property, what is going on around that; certainly all producers will be very vigilant.”

The most recent bird flu outbreak began last year in Europe and has since spread to the United States and Canada, devastating commercial farms with its very high mortality rate.