The body aches accompanied by a low-grade fever are usually due to the following factors: 1. The most common factor is an infectious factor, whether it is bacterial, viral, fungal or other pathogenic microorganisms, such as mycoplasma and chlamydia infections, there is a release of inflammatory mediators in the body, such as interleukin 2, interleukin 6, leukotrienes, bradykinin and prostacyclin. These inflammatory mediators in the body will produce fever in addition to the inflammatory factor effect of peripheral aches and pains.2. The above symptoms can also occur when there are some non-infectious factors, such as the appearance of connective tissue disease or immune complexes, immune diseases, like rheumatoid arthritis, dermatomyositis, systemic lupus erythematosus, and dry syndrome, all of which have clinical symptoms of peripheral aches and pains and low fever.3. In the human body Immunity is extremely low, such as anemia, tumor, tuberculosis, AIDS, etc., will also appear pain all over the body and low fever.