Blood disorders can affect any of the three main components of blood:
Red blood cells, which carry oxygen to the body's tissues
White blood cells, which fight infections
Platelets, which help blood to clot
Blood disorders can also affect the liquid portion of blood, called plasma.
Treatments and prognosis for blood diseases vary, depending on the blood condition and its severity.
As many as 100,000 people in the United States have the disease, which causes red blood cells to resemble sickles or crescents. The misshapen cells can reduce blood flow, which starves vital organs of oxygen and can lead to chronic fatigue and intense pain.
Many people who don't have the disease carry a gene for it. Screening is essential, a message Tate will spread this month via Facebook and Twitter (@LarenzTate). "If you can prevent the disease, you can really make a difference in someone's life," says Tate.
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