U.S. scientists have used reverse genetics to develop an influenza virus with two key proteins on its surface derived from the H5N1 avian virus strain.
As nations stockpile vaccines against H5N1, the strain of influenza virus that experts fear could cause the next flu pandemic, researchers are unsure if the vaccines will remain effective as the virus mutates.
Dr. Elena Govorkova, Robert Webster and colleagues at St. Jude Children's Research Hospital in Memphis, say they inactivated the virus and used it to vaccinate ferrets.
They said the vaccine protected ferrets from becoming sick when exposed not only to the flu strain from which the vaccine was made, but also two other strains, including a deadly strain labeled A/Vietnam/1203/04.
Cross-strain protection is what would been needed in a pandemic, since it would protect against newly emerging variants until a strain-specific vaccine could be developed.
The scientists said the reverse genetics method they used would allow rapid vaccine preparation, which would be crucial in a fast-moving pandemic.
The study will appear in the July 15 issue of The Journal of Infectious Diseases and is available online.
Copyright 2006 by United Press International
Explore further: Using cold adaptation to produce safe inactivated polio vaccine candidates