Lupus erythematosus is not contagious through sharing meals or living together. It is an autoimmune disease, not an infectious one, hence it cannot be transmitted to others by living or eating together. The exact mechanism of lupus is currently unclear, but it may be related to various factors such as sex hormones, genetics, infections, and physical and chemical factors, and it is more commonly seen in females. Clinically common symptoms include fever, rash, joint pain, oral ulcers, hair loss, etc. The clinical manifestations vary depending on the affected target organ. If lupus nephritis occurs, symptoms such as edema can appear. If the lungs are involved, it can promote pulmonary interstitial fibrosis, and in severe cases, patients may experience chest tightness, shortness of breath, and breathing difficulties.