Four cases of cholera were diagnosed at a displaced persons camp in the city of Galle in Sri Lanka, a spokesman for the aid organization World Vision, Soenke Weiss, reported Saturday. "We fear that that cholera will spread through the region like wildfire," Weiss said six days after the tsunami catastrophe that struck South Asia. There are around 1,500 people in the affected camp, including 300- 500 orphaned children. Galle is about 120 kilometers south of the country's capital Colombo.