A further six commercial poultry farms in western Canada have been found within the last week to be infected with bird flu, bringing the total number of infected farms to 37 since the outbreak began.

Since the disease was discovered at a farm in Fraser Valley, British Columbia in February, officials have been struggling to contain the disease, which has spread far beyond the original ‘hot zone’ in recent weeks.

Earlier this month, Canadian officials decided to order the slaughter of all 19 million chickens and turkeys in the region to prevent the spread of the disease. Most of the birds will be slaughtered and sent to market, while those that are found to be infected with the disease, or have come into contact with infected birds, will be disposed of. All birds within a 1km radius of an infected farm will have to be destroyed, reported the Canadian Press.