Baby has a fever of 39°C but is in good spirits—why, and what to do

Generally speaking, fever refers to elevated body temperature. If a baby has a fever up to 39°C but remains in good spirits, it may be related to vaccination reactions, catching a chill, upper respiratory tract infections, infantile emergency rash (roseola), pneumonia, or other factors. Timely general or medication treatments should be administered according to the underlying cause. If the fever persists, prompt medical attention is necessary. Detailed explanations are as follows:

1. Vaccination Reaction

If the baby has recently received a vaccination, the immune response triggered by the vaccine may cause fever, usually without other symptoms. Wiping the body with lukewarm water may help reduce the temperature. If necessary, medications such as acetaminophen oral solution, ibuprofen suspension drops, or compound pediatric fever suppositories may be used according to medical advice.

2. Exposure to Cold

If the baby gets chilled due to insufficient warmth during cold weather, similar symptoms may appear, possibly accompanied by headache and fatigue. It is important to keep the baby warm and dress them appropriately. If symptoms are severe, medications such as pediatric cold and fever syrup, paracetamol chlorpheniramine maleate granules, or pseudoephedrine drops for children may be considered under medical guidance.

3. Upper Respiratory Tract Infection

Upper respiratory tract infection is an acute inflammation caused by bacterial or viral infection. With increased inflammatory mediators, the body may develop persistent high fever, possibly accompanied by coughing and runny nose. Treatment may include ribavirin granules, common cold granules for children, or Lianhua Qingwen granules, used according to a physician's instructions.

4. Infantile Emergency Rash (Roseola)

Infantile emergency rash is caused by viral infection. After the virus stimulates the body and inflammatory cells increase, persistent high fever can occur, often accompanied by skin redness and mild diarrhea. It is recommended to use acyclovir granules, Xiao Chai Hu granules, or calamine lotion according to medical advice. At the same time, the skin should be washed with warm water regularly to prevent bacterial residue.

5. Pneumonia

Pneumonia is another infectious disease caused by pathogens such as bacteria or mycoplasma. During the acute phase, persistent high fever may occur, usually accompanied by shortness of breath and difficulty breathing. Treatments may include amoxicillin-clavulanate potassium granules, oseltamivir phosphate granules, or ambroxol hydrochloride and clenbuterol oral solution, used as directed by a physician.

It should be noted that even if a baby remains in good spirits, persistent high fever must be taken seriously and treated promptly to prevent disease progression. Additionally, during treatment, exposure to causative factors should be avoided to prevent recurrence.