A mild form of avian flu has been discovered at a second farm in southwestern British Columbia, but Canadian officials said the public health risk remains minimal.

According to the Canadian Food Inspection Agency, the virus was discovered during tests of birds at farms within 5 km (3 miles) of a facility near Abbotsford, British Columbia, where a duck was found last week to be carrying the virus.

The virus is believed to be a low-pathogenic H5 strain found in North American fowl, which causes mild illness in birds but does not spread to humans and is not the same strain that has raised human health concerns in Asia and Europe.

The new case was associated with the original farm, and officials suspect the infection may have been spread by equipment traveling between the operations.

It seems no virus was found at three other farms owned by the same family.

Cornelius Kiley, a CFIA veterinarian says the cases are a very localized event.

Although the birds were found to be carrying the virus none of them were sick.

The initial outbreak found in the duck is thought to have been spread by wild waterfowl that often carry the disease and migrate through the area.

In order to prevent the virus from spreading, all birds at the second farm will be culled.

As many as 60,000 ducks and geese at the original farm have already been killed.

The United States, Taiwan and Hong Kong have imposed interim bans on poultry from British Columbia, which exports only small percentage of its production, while Japan has banned all poultry from Canada.

An outbreak of an H7 strain of bird flu in southwestern British Columbia’s Fraser Valley last year prompted officials to kill an estimated 16 million birds even though that strain of flu also does not cause disease in humans.