New technique provides supplies of seed viruses to fight bird flu

Nov 1 2005

Researchers in the U.S. believe that a new manufacturing method may allow large quantities of vaccine to quickly be deployed against a deadly bird flu pandemic.

The scientists say they have found a more efficient way to produce the disarmed viruses that form the basis of anti-flu vaccines.

The researchers from the University of Wisconsin-Madison in the U.S. employed a "reverse genetics" technique to increase the rate at which monkey kidney cells produce raw viruses by making it easier for the viral genes to commandeer the monkey cells' reproductive machinery.

These are then implanted in chicken eggs to generate vaccines against specific viruses such as H5N1, the lethal strain currently threatening to mutate and spread from humans.

According to Dr Yoshihiro Kawaoka, who led the team, the application of the new system may be especially advantageous in situations of outbreaks of highly pathogenic avian influenza viruses.

Many experts fear that H5N1 bird flu will soon mutate or combine with another virus to become transmissible between humans, triggering a pandemic that could kill up to 50 million people around the world.

It is impossible to produce an effective vaccine until the nature of the mutated strain is known.

Once it is identified, scientists will then be in a race against time to produce enough vaccine before the spread of infection gets out of control.

This new technique promises to ensure a ready supply of "seed" viruses which can then easily be modified to be effective against dangerous strains.