Scientists have identified Helico- bacter pylori, a bacteria that causes stomach ulcers, in contaminated water, thus giving a clue to the source of infection.

Earlier studies were unable to detect the presence of Hpylori in the environment, but its strong link with drinking water was never discounted. Preliminary results of studies conducted by Massachusetts Institute of Technology scientists have shown the presence of the bacteria in a water sample from Narino, Columbia where ulcer infections are common.