Wendy Barclay is one of the leaders of the gene-editing project. She is a professor of virology at Imperial College London. She said the first chickens will be born later this year at the Roslin Institute at the University of Edinburgh in Scotland.
The scientists are using a new gene-editing technology known as CRISPR to change the birds' DNA. The scientists removed parts of a protein on which the flu virus normally depends. That makes the chickens completely flu-resistant.
Barclay said the idea is to produce birds that cannot get the flu and would form, in her words, a "buffer between wild birds and humans."
Health experts say the threat of a human flu pandemic is one of their biggest concerns.
About 500,000 people died worldwide in the last large flu outbreak in 2009 and 2010. The historic 1918 Spanish flu killed around 50 million people.
The greatest fear now is that a deadly form of flu could spread from wild birds into poultry and then into humans. The virus could then become an airborne form that can pass easily between people.
"If we could prevent influenza virus crossing from wild birds into chickens, we would stop the next pandemic..." said Barclay.
Barclay's team of scientists published their research in the journal Nature in 2016. They found that a gene present in chickens makes a protein that all flu viruses depend on to infect a host. Tests of cells created to not have the gene showed they cannot be infected with flu.
Barclay said the plan is to use CRISPR to edit the chickens' DNA so that only one part of the protein is changed. The rest of the bird would be exactly the same as it was before.
Barclay said poultry producers may have concerns about the public's opinions of gene-edited food. She said that people have been eating food from farmed animals that have been changed over many years by traditional breeding.
But she added, "They might be nervous about eating gene-edited food."
I'm Jonathan Evans.