A team of Indian scientists has revealed that a prototype of a hand-held breathalyser for detecting tuberculosis infection could be available within two years.

The team has won a 950,000 dollars grant to build a prototype "electronic nose" by the end of 2013 which will detect the early stages of the respiratory disease, which claims nearly 1.7 million lives a year worldwide.

The TB breathalyser works by detecting the presence of about half a dozen biological chemicals in the air expelled from someone's lungs.

This form a reliable signature of TB infection, said Peter Singer, chief executive of Grand Challenges Canada, which is part-funding the development with the Bill and Melinda Gates Foundation.

"The scientists have proven that patients with TB have a different signature on their breath compared with people who do not. Now they are validating it and putting it into a machine," the Independent quoted Dr Singer as saying.

It is estimated that up to 400,000 lives a year could be saved in the developing world by the early diagnosis and treatment of TB.

Ranjan Nanda, one of the scientists in New Delhi, said: "Our goal is to make the electronic nose widely available in poor, remote areas where tuberculosis often breeds and spreads, devastating so many lives."