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How many people worldwide are affected by autoimmune diseases?

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immune system disorder False-color scanning electron micrograph of a T cell infected with HIV (human immunodeficiency virus), the agent that causes AIDS (acquired immunodeficiency syndrome).

It is estimated that between 4 and 5 percent of the global population is affected by autoimmune disease.

These conditions occur when the immune system malfunctions and reacts against the body's own healthy cells. While there are more than 80 known types of these disorders, they are generally categorized as either organ-specific or systemic. Research indicates that females are affected by these conditions more frequently than males, a disparity that scientists believe may be linked to hormonal influences on immune responses.12

Factors contributing to the development of these diseases include a combination of genetic predispositions and environmental triggers, such as exposure to certain chemicals or infections. Lifestyle factors, including obesity and smoking, can also increase an individual's risk. Because the majority of these conditions currently lack a cure, treatment typically focuses on managing symptoms through medications that reduce pain and inflammation.12