A report from the UK Department of the Environment, Food and Rural Affairs has found that 156 outbreaks of bird flu have been confirmed in the country between December 2014 and May 2015. This is the most extensive epidemic ever reported in the country. To date 60 wild birds have tested positive for avian influenza in states across North America and almost 32 million birds have been affected in culling measures.

In Europe cases have been reported in Bulgaria, Romania, Russia and Turkey, while in west Africa Burkina Faso has reported 22 cases since March 2015. Outbreaks have also been reported on the Niger and Nigeria borders.

The report says this year continues to be unprecedented in terms of the frequency of avian influenza outbreaks, the regions affected and the role of wild birds, trade or population movement and poor biosecurity in increasing incursion risk and transmission. The significant spread across short distances in the USA has led researchers to look into the possibility of airborne and aerolysed transmission that that has been demonstrated previously such as in the Netherlands in 2003.

Originally, all introductions into poultry farms were considered to be through contact (direct or indirect) with wild birds, either by contaminated footwear or clothing on poultry workers or contaminated equipment and bedding.