Is it dangerous for a child to have a fever of 39°C?

Whether a child’s fever reaching 39°C is dangerous generally depends on the child’s overall condition and the underlying cause of the fever.

In general, younger children are more susceptible to complications from high fever. A temperature of 39°C may trigger febrile seizures or convulsions, electrolyte imbalances, or marked increases in heart rate and respiratory rate—conditions that can significantly disrupt normal metabolic processes. Therefore, a fever of 39°C in children is often considered potentially dangerous.

If the fever results from a severe infection—such as central nervous system infection—the danger stems primarily from the underlying disease itself rather than the fever per se. Conversely, if the child remains alert and active, is older, and has only a mild illness, a fever of 39°C may not necessarily pose an immediate threat.

When a child develops a fever of 39°C, prompt medical evaluation is recommended. Treatment should target the underlying cause of the fever. Additionally, physical cooling methods—such as tepid sponging or applying a cooling patch to the forehead—may be used as adjunctive measures.