Under normal circumstances, if daily fever is due to the following factors: 1. For some infectious factors, such as bacteria, viruses or mycoplasma, atypical pathogens, fungi, these pathogens will produce a certain immune response when infected with the body, so the body will appear endogenous pyrogens, pyrogens can lead to fever every day. 2. In some non-infectious factors, such as basal metabolic rate In some non-infectious factors, such as high basal metabolic rate diseases, such as hyperthyroidism, hyperadrenocorticism, will produce daily fever. 3, in some, such as immune diseases, connective tissue diseases, can also lead to daily fever, such as rheumatoid arthritis, dermatomyositis, systemic lupus erythematosus, dry syndrome, this immune-based disease will also appear daily fever, and finally, in some, such as some rare diseases, such as tumors, serious diseases, and so on, the body will appear endogenous pyrogens, pyrogens will lead to daily fever. Rare diseases such as tumors, severe anemia, and AIDS can also cause daily fevers.