A new way of delivering vaccines could help revolutionise immunisation programmes in the developing world by eliminating costly and often incomplete refrigeration, the scientists responsible for the technology said yesterday.

The system involves storing the active ingredients in solid microscopic sugar "beads".

If it works the technique should help end the annual loss of about half the vaccination packages to bacterial contamination or damage by extremes of temperature.

The beads, suspended in inert biochemical oils, are rehydrated and returned to life by body fluids when injected.

The first tests on humans will be conducted in India over a three-year period using a five-in-one jab against tetanus, diphtheria, whooping cough, hepatitis B and haemophilius influenza type B (Hib), which can cause meningitis.

The technique should work against most other infections too, according to its developers Cambridge Biostability, although the polio vaccine has proved impossible to crack.

The company's scientists and advisers believed the system could save millions by eliminating the "cold chain", which costs up to $300m (£166m) a year, from the vaccine system, even though some vaccines may cost more to manufacture in this form.

This would allow an additional 10 million children to be vaccinated on existing budgets, the company claimed.

The company has spent about £2m on the technology, and the Department for International Development is providing £950,000 to help bring the idea to market.

The Indian company Panacea Biotech in New Delhi is to manufacture the trial vaccines.

Although it is aimed first at the developing world, the technique may offer the potential of "slow release" vaccine which would need fewer boosters.

It might also be adapted to stockpile vaccine defences against bio-terrorism, and to deliver other types of new drugs.