October 22, 2008
US scientists have invented a bird flu vaccine that could be used to protect several species against different influenza viruses, including humans, poultry and even pets.
A single vaccine could now be used to protect humans, birds and mammals against different flu strains and can be given to birds while they are still in their eggs, according to the Journal of General Virology.
Professor Daniel Perez from the University of Maryland in the US, leading the research, said the H5N1 virus has an unusual expanded host range which includes not only birds and humans but also cats, which are usually resistant to influenza.
In order to adequately prepare for such a pandemic, a vaccine should be able to be used in multiple animal species, he added.
The key lies in the central genes or 'backbone' of the H9N2 virus that infects guinea fowl. The team found that inactivated genes of the virus can protect birds and mice against highly pathogenic strains of influenza.
The virus was used to vaccinate mice which later survived infection with the deadly H5N1 bird flu virus and the potentially H1N1 virus, showing no signs of disease.
The genes from H9N2 influenza was used in the vaccine because the virus can infect many different animals, including chickens, mice and pigs, said Prof Perez.
So far, vaccines in the market have been species specific, but this vaccine could be used in multiple species, Prof Perez said.
The vaccine also provided effective protection when it was administered to birds before they had hatched. By vaccinating eggs against influenza, domestic chickens as well as wild bird species could be protected, he added.