Small red dots on the chest have to be analyzed specifically whether they are caused by allergies or infections. If it is caused by allergies, anti-allergy treatment is needed. If it is caused by an infection, it is important to distinguish whether it is a bacterial infection or a viral infection, a systemic infection or a local infection. If it is a systemic infection, such as systemic respiratory tract infection, respiratory tract bacterial infection causing scarlet fever, can also be manifested as small red dots on the face, chest, neck, hands and feet, like the size of small grains of rice, generally with a certain amount of itching, the patient may be accompanied by fever, elevated blood count, etc., this should be treated with antibiotics anti-infection. If it is a viral infection, generally the white blood cells are reduced, lymphocytes or monocytes are elevated, and blood tests are required. If it is a local infection, it may be folliculitis, which can also be manifested as small red dots, small papules or papules, and should be treated locally with symptomatic treatment, applying some anti-inflammatory creams on the symptoms. If it is an allergic disease, we need to find out the cause of the allergy and then anti-allergy treatment, so we need to analyze the specific aspect of the cause of the small red spots.