Vaccine breakthrough could revolutionise Third World health

Last updated at 11:57 19 October 2004

British scientists have made a breakthrough which allows vaccines to be stored for years without refrigeration, it emerged today.

The development could revolutionise public health programmes in the Third World, where vital vaccines frequently have to be thrown away because they have not been kept cold enough.

The new technology uses a natural process seen in living organisms like the desert-dwelling resurrection plant, which dries up completely in drought conditions only to burst into life when rain arrives.

Dr Bruce Roser, of Cambridge Biostability, today said that clinical trials of the procedure on humans could be started within three years.

He explained how the resurrection plant survives over long periods in the absence of liquid thanks to a sugar which becomes as hard as glass when dry.

"They use an unusual but simple sugar which has the property of turning into a thick syrup when it dries out, rather than crystallising," he told the BBC Radio 4 Today programme.

"We have taken this technology and made it work on the lab bench. We have put these vaccines in a solution of this syrup.

"We dry it and it turns into a syrup which becomes more and more viscous as we remove more and more water until imperceptibly it solidifies as a glass.

"It is very similar to fossilised insects trapped in amber which are preserved for millions of years."

The technique has already been tested on four commercial vaccines, which were found to be "stable and efficacious" in animal trials.

The Cambridge-based company has received grants from the Department for International Development and is working with an Indian vaccine company to prepare for trials on humans, said Dr Roser.