Bird Flu: CRISPR Gene-Edited Chickens May Save Us From the Next Pandemic
They're expected to hatch this year in Scotland.
Humans don’t usually get the flu directly from animals, but human outbreaks of bird and swine flu can and do happen. In fact, scientists are so concerned that the next great pandemic will arise from a deadly strain of wild bird influenza that they’ve created what will hopefully be our feathered saviors: Gene-edited chickens that are totally resistant to the flu.
Reuters reported Sunday that this first batch of “transgenic” chicks is expected to hatch sometime in 2019 at the Roslin Institute at the University of Edinburgh in Scotland. The Roslin Institute is the institution where Dolly the sheep, the world’s first cloned mammal, was famously created and born.
Wendy Barclay, Ph.D., a professor of virology and the co-leader of this project, told Reuters that the goal is for these hatchlings to serve as a “buffer between wild birds and humans.” She adds that if these chickens are able to “prevent influenza virus crossing from wild birds into chickens, we could stop the next pandemic at [the] source.”
To date, avian influenza A viruses have been identified in more than 100 different species of wild birds. And while infected wild birds do not often get sick from these contagious viruses, they can pass on the illness to domesticated bird species — which often get sick and die. Agencies like the Centers for Disease Control and Prevention are concerned about avian flu’s ability to transition from a low pathogenic virus in the wild to a highly pathogenic virus in domesticated chickens, as well as the possibility that avian influenza A viruses can be transmitted to humans.
An avian influenza strain that’s already concerning public health officials is Asian highly pathogenic avian influenza (HPAI) A(H5N1), which was first detected in geese in China in 1996 — and first detected in humans in 1997 during a poultry outbreak in Hong Kong. There was a widespread re-emergence of H5N1 in 2003, and since then sporadic human infections have been reported in Asia, Africa, Europe, and the Middle East. It has never been reported in humans in the United States, but in 2014 a human infection was reported in Canada. For humans infected by H5N1, the mortality rate is about 60 percent, reports the World Health Organization.
Barclay and her team hope to stop these illnesses, in part, with these future transgenic chickens. In 2016, the team discovered that a gene called ANP32 encodes a protein that avian flu viruses depend on to infect the animal. Now, a plan is in the works for the team to use the gene-editing technique CRISPR to remove ANP32, in turn making the birds flu-resistant.
Previously, the team created chickens that could become sick but did not pass on the infection — now the idea is that these new hatchlings will not become ill at all and therefore can not be a bridging host that will infect humans with new strains of flu. The main issue Barclay anticipates? Getting people to eat them, once they replace traditional flu-vulnerable populations.
“People eat food from farmed animals that have been altered by decades of traditional breeding,” Barclay says. “But they might be nervous about eating gene edited food.”