The findings, which are published in the journal Scientific Reports, show that genetics play a key part in whether the birds are susceptible or resistant to the potentially deadly virus.

Dr Colin Butter, Reader in Bioveterinary Science at the University of Lincoln, who carried out the research, said: “It is important for us to understand how different genetic lines of birds react to influenza viruses, so that we can begin to understand the spread of the disease.

"Our results are valuable in emphasising the important role a ‘host’ plays in the spread of avian flu, and also in highlighting a number of factors relating to the chain of infection and control mechanisms which are affected by the route of infection.”

They found that birds that carried the virus but were genetically resistant to the disease only shed the virus through their respiratory tract and for a limited period of time, whereas birds which were susceptible to the disease, also shed virus in faeces and over a longer time. The researchers discovered that this was the only relevant means of spreading the virus and that resistant birds were therefore unable to initiate or sustain the chain of transmission.

Further results in the study suggest that this could be due to a genetic restriction within the animal which stops the virus spreading when inside the body.

Work is being planned to discover and examine the precise biological mechanisms behind genetic resistance. This could have major implications for poultry breeding, as well as human flu treatments, in the future.

Further Reading

You can visit the avian flu page by clicking here.