Winter flu shot
may protect against avian flu

A yearly flu shot may protect you from bird flu, according to research at St. Jude Children's Research Hospital.

Immunity to the H5N1 virus, known commonly as bird flu, appears to come from antibodies produced in response to the neuraminidase (N) protein in the flu shot. That protein signals the body to make antibodies, which research showed effective in fighting off the bird flu virus.

While results are still preliminary, Richard Webby, assistant member in the virology division of the Department of Infectious Diseases at St. Jude, said in a statement: "The presence of the N1 protein in both the human flu and the bird flu virus helped to convince us to look for evidence that immunity to human strains of flu might also trigger some antibody response to H5N1."

Another protein responsible for protection from both influenza and bird flu is hemagglutinin, or "H." Because hemagglutinin is more common than neuraminidase on viruses--5 to 1 in bird flu--vaccines are commonly designed to trigger an immune response primarily to hemagglutinin. However, these findings may change that, said Matthew Sandbulte, a researcher for this study and a postdoctoral fellow at the Food and Drug Administration, in a release. "Vaccines contain standard amounts of hemagglutinin but varying amounts of neuraminidase. But if further research confirms that the N1 part of the influenza vaccine offers some cross protection against [the bird flu virus], it will be desirable to have a better idea of the amount of N1 present in these vaccines." (The Advocate)