Once a person is affected by a dengue virus, the platelets can no longer âactivateâ itself. So whenever there is damage, the platelets cannot form the mesh structure and the blood flows out of the vessel. As blood flows out, so does the platelets. This causes the platelet count to fall drastically. The blood that flows out causes internal. and external bleeding and leads to a haemorrhage.
1 Today, the Aswan Dam keeps the Nile from flooding modern cities. 2  The Ancient Egyptians called the Nile the Aur, which means black and comes from the black soil. 3  The Egyptians measured the height of the annual flood using a Nilometer.
The blessings of the Nile were many, but they did not come without some costs. A low flood could lead to famine, and too high a flood could destroy dikes and other irrigation works. Even a 2-meter drop in the river's flood level could leave as much as a third of the floodplain unwatered. [7].