Cancer and certain blood disorders

People who currently have cancer are at higher risk of developing more severe illness from COVID-19. This risk can vary, depending on the type of cancer and the kind of treatment you're receiving.

Sickle cell anemia is another condition that increases the risk of severe COVID-19 symptoms. This inherited disorder causes your red blood cells to become hard, sticky and shaped like the letter "C." These deformed red blood cells die early, so oxygen can't be transported around your body as well. It also causes painful blockages in small blood vessels.

Another inherited blood disorder, called thalassemia, might also make you more likely to have serious COVID-19 symptoms. In thalassemia, the body doesn't produce enough hemoglobin and this affects how well the red blood cells can carry oxygen.