Vaccines could be stored for years without refrigeration thanks to a technological breakthrough whichpromises to revolutionize public health care, British scientists said Tuesday.

    The new "stable liquid" technology will enable vaccines to be stored for long periods in a range of environmental conditions, removing the need for refrigeration and reconstitution, said BruceRoser, chief scientist at Cambridge Biostability Limited (CBL), which developed the technology.

    Almost 30 million children around the world have no access to immunization and nearly two million die yearly from illness which could be prevented by vaccines, according to the World Health Organization.

    The so-called "cold chain" is a major burden to vaccine programs, which requires a stable electricity source to continually chill the vaccine. Currently 50 percent of all vaccines are wasted partly due to suspected or real temperature damage.

    The new technology uses a natural process, called anhydrobiosis,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, Roser told a news conference atthe British Royal Society of Medicine in London.

    The plants "use an unusual but simple sugar which has the property of turning into a thick syrup when it dries out, rather than crystallizing," he explained.

    "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," he added.

    The new technology also offers the potential of slow release vaccine, which may overcome the need for boosters, says CBL.

    In the first stage, CBL aims to develop a fridge-free five-in-one vaccine to immunize against diphtheria, tetanus, whooping cough, Hib (haemophilus influenza type B) and hepatitis B, said Roser.

    The British government has granted CBL 950,000 pounds (1.71 million US dollars) to prepare its technique for clinical trials. The company is working with Panacea Biotec, a New Delhi-based Indian company, to test the vaccine on human beings.

    Rosser says it will be at least five years before the vaccine system is available commercially.