Authorities closed the Cairo zoo Sunday after six of 83 birds that died there recently tested positive for the deadly H5N1 strain of bird flu. Health authorities said tests still had not found the disease in humans. Egyptian officials, meanwhile, pleaded with citizens not to dispose of dead chickens, turkeys or other birds by throwing them in the roads, irrigation canals or the Nile River. The officials reported eight other new bird flu cases in Cairo Sunday. Agriculture Minister Amin Ahmed Abaza said he closed the zoo, located across the Nile from Cairo in the city of Giza, after the death of ducks, turkeys and Chinese geese. He said 563 birds at the zoo were destroyed as a precaution and ponds were drained. "The biggest problem, however, is with people who raise poultry on rooftops or balconies in the cities. We need to avoid any direct contact between birds and human," he said. Health Minister Hatem Mustafa el-Gabaly, meanwhile, appealed to Egyptians to properly dispose of dead birds. "Please do not throw these things into the street. And most hazardous: Do not dispose them into the Nile. Please do not throw them into the Nile."