White tongue coating is not a basis for diagnosing AIDS. Tongue coating is a thin white layer of moss on the back of the human tongue, and in normal people it is thin and white. According to Traditional Chinese Medicine (TCM), when the tongue coating becomes white and thick, it indicates that there may be phlegm-dampness in the body or food accumulation (the accumulation of food in the stomach due to indigestion). AIDS is an immunodeficiency disease caused by human immunodeficiency virus (HIV) infection, and the HIV-1/2 antibody test is the gold standard for detecting HIV infection, which manifests itself in different stages of development. Acute HIV infection is characterized by fever, malaise, sore throat and flu-like symptoms. Asymptomatic HIV infection may not have any clinical manifestations. Patients who have progressed to the AIDS stage have fever, diarrhea, weight loss, enlarged superficial lymph nodes, etc., and are often combined with various conditional infections, such as oral Candida infection and Pneumocystis carinii pneumonia. There is no cure for AIDS, and the key to prevention lies in changing high-risk behaviors, using condoms correctly, not using drugs, and not sharing needles.