June 9, 2015
Novel bird-flu vaccines ''kill 2 birds with 1 stone''
Wenjun Ma, assistant professor of diagnostic medicine and pathobiology at Kansas State University, left, and Jürgen Richt, Regents distinguished professor of veterinary medicine and director of the US Department of Homeland Security''s Center of Excellence for Emerging and Zoonotic Animal Diseases PHOTO FROM WEBSITE OF KANSAS STATE UNIVERSITY
A vaccinefor the deadly H5N2 bird-flu virus that has resulted in the killing of over 26 million chickens and turkeys in the US Midwest may soon be developed after researchers at Kansas State University have come up with vaccines against the H5N1 and H7N9 strains using a novel method.
The researchers, led by Jürgen Richt, a professor of veterinary medicine and director of the US Department of Homeland Security''s Center of Excellence for Emerging and Zoonotic Animal Diseases based in Kansas State U, said the method they used in developing the new vaccines is expected to help other researchers make vaccines for emerging strains of avian influenza more quickly.
Richt said it may also lead to new influenza vaccines for pigs and novel vaccines for sheep and other livestock.
In creating the vaccine for H5N1, the researchers worked with an existing vaccine used against the Newcastle disease virus, which naturally affects poultry. They cloned this vaccine and then transplanted a small part of the H5N1 virus into the clone, creating a recombinant virus.
Tests showed that chickens vaccinated with the recombinant vaccine protected them against both the Newcastle disease virus and H5N1 strain of bird flu.
The same procedure was used to create the vaccine for H7N9, and this had similar results in vaccinated chickens.
"We believe this Newcastle disease virus concept works very well for poultry because you kill two birds with one stone, metaphorically speaking," Richt said. "You use only one vector to vaccinate and protect against a selected virus strain of avian influenza."
Richt said using the Newcastle disease virus for vaccine development may extend beyond poultry to pigs, cattle and sheep.
The researchers found that by using the Newcastle disease virus to develop a recombinant virus vaccine, they were able to protect pigs against an H3 influenza strain.
Wenjun Ma, Kansas State University assistant professor of diagnostic medicine and pathobiology and a member of the research team, is using the Newcastle disease virus to make a vaccine for porcine epidemic diarrhea virus, a disease that has killed around 6 million piglets in the US.
According to Richt, the newly developed bird-flu vaccines are already being produced by a firm in Mexico.