We have seen many cases of convulsions and repeated convulsions caused by excessive warmth and multiple organ failure during the postgraduate period, so we would like to inform you. The muffled fever syndrome, also known as “infant cover hypoxia syndrome” or “infant smothering syndrome”, is a common winter emergency due to hypoxia, high fever, profuse sweating, dehydration, convulsions and coma, and even respiratory and circulatory failure caused by over-warming and smothering for too long. Infants within 1 year of age, especially newborns, are at the peak of the disease from November to April each year. If the child is wrapped too warmly (e.g., in winter, the child is given 3 layers of warm blankets or is covered with multiple layers of clothing after wearing warm clothes), the child will sweat profusely in the early morning or without the adult being aware of it, and will not be able to respond to calls, convulsions, and coma. The result is often dehydration and electrolyte disorders, and even multi-organ failure (myocardial enzyme profile, liver function, etc. can be seriously abnormal), often manifested by heavy sweating, breathing difficulties, shortness of breath or irregularity, gray face, lips and nails blue and other respiratory failure symptoms, hypoxia can lead to convulsions, seizures or coma occur when serious. It can also lead to shock or even death very quickly. Children who are fortunate enough to survive are often left with severe sequelae of brain injury such as mental retardation, motor impairment, dumbness, deafness, and epilepsy. Therefore, in winter, do not over-warm your child.