A joint South Korean-U.S. team of researchers has discovered the mechanism that escalates the virulence level of cholera germs.

A research group led by Seoul National University Professor Chun Jong-shik and a group led by Doctor Kim Dong-wook at the International Vaccine Institute made the recent discovery with researchers at the University of Maryland.

The discovery was made after the DNA of 23 types of cholera germs collected since 1910 had been successfully deciphered.

Researchers said they discovered some 70 gene groups that fluctuate between cholera germs.

Professor Chun said the recent discovery will facilitate efforts to find the virulent element of new cholera germs and develop vaccines.

The recent research results can be found on the U.S. science Web magazine, Proceedings of the National Academy of Sciences.