1.   Another idea is to develop transgenic cattle that carry the yeast molecule, he said.

2.   At the first sign of a cold, people could spray the yeast molecules into their noses or throats, Dasgupta said.

3.   Dasgupta said the yeast molecule should be completely benign to living human cells.

4.   Despite the momentary euphoria, the seasoned researcher said he knows he is far from verifying that the yeast molecule will cure colds, or polio and hepatitis.

5.   Nevertheless, the findings are preliminary and it will be at least two years before the yeast molecule is tested in humans.

6.   Specially designed drugs could carry the yeast molecule directly to the liver, where it would stop hepatitis A virus from replicating.

7.   The discovery of the yeast molecule is described in the November issue of The Journal of Virology.

8.   The yeast molecule interferes with this step in the process, Dasgupta said.

9.   The yeast molecule is now under close scrutiny, but it will be at least two years before it can be tested in humans.

10.   The yeast molecule has no effect on other types of viruses, including the HIV virus that causes AIDS and the influenza virus.