Overview: World Sickle Cell Anemia Day is commemorated every year on 19 June. Sickle cell anemia is defined as a group of inherited red blood cell disorders. Healthy red blood cells are round and move through small blood vessels to transport oxygen throughout the body; But in the person with sickle cell anemia, red blood cells become hard and sticky, and look C-shaped. Sickle cells die early; Which leads to a constant shortage of red blood cells.