Partial Immortality

A superdrug that protects against all the most deadly types of flu has been developed by scientists. Could a cure for Paris Hilton's herpes be next?

A single injection of the anti-viral medicine can fight off everything from a common winter virus to a life-threatening strain of bird flu, researchers say. The breakthrough brings closer the Holy Grail of influenza treatment - a oneshot vaccine for lifelong protection against every imaginable type of the virus. Researchers believe the new drug, which uses man-made antibodies, could be available in less than five years. A vaccine would follow soon afterwards.

Flu experts say it is only a matter of time before the world is struck by another pandemic like the one which killed millions in 1918. They are most concerned about the deadly H5N1 strain of avian flu which has killed 200 people, mostly in Asia. If H5N1 mutates into a form that spreads easily from person to person, it could kill tens of thousands before being managed. The new drug has the potential to save many thousands of lives during a pandemic. Stockpiles could be used to keep influenza at bay during the four to six months it would take to develop a new vaccine.

Professor Peter Openshaw, an expert in respiratory disease at the National Heart & Lung Institute, Imperial College London, said the breakthrough could lead to vaccines within a few years. "I don't think it's realistic to imagine making this antibody as a treatment, but the fact that it is possible for antibodies to be so broad raises the possibility of vaccine that would work from one year to the next - as well against as-yet undiscovered types of flu. We could imagine a vaccine that works against all winter flu strains and also protects against unknown future pandemics. That would be a major breakthrough."

Antibodies work by seeking out proteins on the surface of a virus and attaching themselves to them. The virus is disabled and unable to invade the body's cells to make copies of itself. Most vaccines and antibodies target a part of a protein which mutates very easily - and changes from year to year. That is why new vaccines are needed each flu season. But the U.S. researchers targeted a different part, one that is identical across a huge range of flu viruses. In laboratory experiments, reported in the journal Nature Structural and Molecular Biology, the antibodies disabled eight strains of virus, including H5N1 and the 1918 'Spanish Flu' strain.

Dr Wayne Marasco, from the Dana-Farber Cancer Institute and Harvard Medical School in Boston, said, "At-risk individuals, such as medical personnel, exposed family members and co-workers and patients who cannot make antibodies because of medical conditions or age, could all benefit from this new therapy." Clinical trials on people are due within 18 months. If the antibodies are shown to be safe, they could available in five years.