Repeated fever does not go away for 6 days, the causes are viral infection, bacterial infection, heat stroke, suffering from certain infectious diseases, etc. In addition, non-infectious diseases can also cause repeated high fever symptoms, such as immune system diseases, tumors, craniocerebral diseases, etc. Repeatedly high fever does not go away, considering that the cause of the disease has not yet been completely removed, and only if the cause of the disease is removed, the symptoms of fever can be relieved. 1. Viral infections: such as viral colds, viral pneumonia, viral encephalitis, etc. In addition to antipyretic and targeted treatment, antiviral treatment can be carried out, and drinking more water during the period of treatment is conducive to the recovery of the disease. 2. Bacterial infections: such as pneumonia, bronchitis, etc., repeated high fever does not go away, may be the cause of the infection is not under control, you can check the blood routine, chest X-ray, etc., if necessary, can be carried out drug sensitivity test, choose sensitive antibiotic treatment. 3. Heatstroke: after heatstroke, the symptoms of infection are easy to appear, when the symptoms are serious, it is easy to appear the symptoms of high fever, can be timely rehydration and symptomatic treatment. 4. Suffering from certain infectious: such as brucellosis, etc., patients generally have a history of contact with animals such as cows and sheep, can go to the hospital for brucellosis examination, anti-infective treatment, such as the application of tetracycline drugs treatment. 3. Non-infectious diseases: such as immune system diseases (rheumatoid arthritis, etc.), tumors (bronchial carcinoma, lung cancer, etc.), craniocerebral diseases (brain tumors, cerebral hemorrhage), hematologic diseases (leukemia), etc., which can also cause recurrent fever symptoms. There are many causes of recurrent fever, and only when the cause of the disease is clearly defined and the treatment is directed to the cause of the disease, the result will be better.