Normal body temperature in children can fluctuate within a certain range. Short-term temperature fluctuations, good general condition, and no conscious symptoms may not be considered pathological. The normal axillary body temperature of children is generally 36-37 ℃ (the following values of axillary temperature), after feeding or meals, exercise, crying, too thick clothing, room temperature is too high can make children’s body temperature temporarily increased to 37.5 ℃, or even 38.0 ℃, newborns or small infants are more susceptible to the above conditions; on the contrary, if starvation, low calories, especially weak children in a state of little movement or poor insulation, body temperature can be as low as 35.0 On the contrary, if starvation, hypothermia, especially in weak children in a less active state or poor insulation, the body temperature can be as low as 35.0 ℃ or below, which is called hypothermia or temperature does not rise, and warming measures should be taken. The time and conditions of temperature measurement and the duration of measurement have an impact on the value; generally, the axillary temperature should be measured for 5 minutes, not too short or too long, too short is low, too long is high. The younger the child is, the poorer the thermoregulation and the greater the temperature fluctuation. However, children’s tolerance for fever is better or less responsive, such as small infants with colds can suddenly increase body temperature up to about 40.0 ℃, while the general condition of the sick child is better, the recovery is faster after the fever subsides. Older children have a more stable body temperature, if the temperature suddenly rises, the general condition is poor, often reflecting the occurrence of more serious diseases. For prolonged fever (>2 weeks) or repeated temperature increases, the primary cause should be carefully identified and analyzed for the presence of complications. Temperature changes in the pediatric period are not as typical as in adults, and in recent years, after early diagnosis and early treatment, especially the increasing application of antibiotic drugs or adrenocorticotropic hormone therapy, have made the temperature curve of many febrile diseases significantly different from the traditional concept, losing the original differential diagnostic significance of the fever pattern. Diagnosis: Diagnosis is a prerequisite for treatment. It should be identified to which system the positive signs other than fever belong, and then combined with age, season, epidemiological data, and necessary laboratory or X-ray findings for differentiation. It should be noted that elevated body temperature is more common in pediatric patients than in adults, and attention should be paid to exclude the influence of external environmental and physiological factors on body temperature. The degree of temperature increase during fever is not necessarily parallel to the severity of the disease, such as children with acute rash, the temperature can be as high as 40 ℃. Second, acute fever in children is mostly seen in infectious diseases: such as respiratory, gastrointestinal, urinary tract, nervous system, different system infections, in addition to fever is accompanied by other symptoms. Some fevers are also seen in heat radiation, massive bleeding, hemolytic crisis, allergic disorders, malignant tumors, and malignant hyperthermia after surgery (prolonged surgery, dehydration, anesthesia, blood or fluid transfusion reaction, bacterial toxins, etc.). For prolonged fever, it is important to observe the fever type, the pattern of fever and the accompanying symptoms of fever, which are beneficial to the diagnosis of the disease, and do not blindly reduce the fever, because blindly reducing the fever can cover up the disease, and is not conducive to the observation of the fever type, pattern and the appearance of accompanying symptoms. If necessary, hospitalization to identify the cause. Third, febrile children must pay attention to age characteristics: fever in infants under 3 months of age should be excluded from serious life-threatening infections, such as sepsis, meningitis, and aseptic meningitis. A history and physical examination can sometimes be helpful. However, in most cases, history and physical examination are not very helpful in making the diagnosis and differential diagnosis, so it is necessary to perform the necessary ancillary tests such as complete blood count (including white blood cell count and classification), sedimentation, blood culture, lumbar puncture, A-screen chest radiograph, urine routine and urine culture, etc. The results of these tests are crucial in deciding whether to apply antibiotics and whether hospitalization is needed. Because of the difficulty in identifying the cause of fever, a decision not to hospitalize for further consultation may be made unless clinical and ancillary investigations are free of any evidence of serious illness, but close follow-up is still needed for safety. fever in infants 3-24 months of age is easier to assess and more reliable than the above group in these children. Foci of infection can often be identified by history and careful physical examination. Viral infections including respiratory tract infections and gastrointestinal infections account for the majority of febrile illnesses in this group and often have systemic and systemically significant symptoms. Bacterial infections include respiratory tract infections, otitis media, pharyngitis, pneumonia, meningitis, etc. Blood cultures are checked when necessary. Some parents of children are afraid of lumbar puncture and bone puncture and laboratory tests, but in fact, bone puncture and lumbar puncture are relatively safe operations, and the diagnosis of the disease is irreplaceable by other tests, and the laboratory tests support clinical diagnosis and guide the use of drugs, so they should not be rejected blindly. The fever can be treated: cooling principles: cooling measures, in addition to fever can cause convulsions, there is no clear evidence that there is any significant harm to children. Therefore, symptomatic cooling should only be considered when febrile convulsions are present and when the child is clearly uncomfortable due to the fever. A combination of cooling measures such as removing excessive clothing, exposing more of the body surface to the air, and hydrating to increase heat evaporation is best, as are wet compresses. Antipyretics can be applied alone, but are more effective when combined with the physical measures described above. Drug antipyretics should be used to avoid drug side effects. Antipyretic drugs: Chinese medicine, Chai Hu, pediatric Chai Gui, antelope horn, Zixue San, Yinhuang granules, taurine, etc. have better efficacy and no side effects, the onset of action may take a long time, but the long-term antipyretic effect is very good, these Chinese medicines must be used under the guidance of a Chinese medicine practitioner regular. Western medicine antipyretic drugs: ibuprofen, acetaminophen is currently a safer pediatric clinical antipyretic agent, is also the WHO recommended drugs, there are many drugs containing these ingredients on the market, have a very good effect, such antipyretic drugs for more than 38.5 ℃, 1 day do not take more than 4 times. If necessary, two drugs can be used alternately.