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 Amazon River does flood and it usually starts in November. The  river floods every year and can swell up to 25 miles and tripling  the land area it cover.he estuary where it meets the ocean is over 200 miles across and deep enough for sea-going vessels to travel nearly 2/3 of the way up the river. Approximately 20% of all of the freshwater in the world that enters the ocean is by way of the Amazon river.