What symptom marks the end of the febrile phase of dengue?

The correct answer, indicating a symptom that marks the end of the febrile phase of dengue, is defervescence. In the context of dengue fever, defervescence refers to the period when the fever begins to decrease or resolve. This is a critical transition point in the illness, as it signifies that the febrile phase, characterized by persistent high fever, is coming to an end.

As the fever subsides, patients may start to feel relief from other accompanying symptoms. This stage is an important indicator for healthcare professionals to monitor, as it can suggest changes in disease progression and the patient's overall condition. Recognizing defervescence helps ensure appropriate follow-up care and assessment for any potential complications that can arise following this phase of the illness.

While the increase in body temperature is often typical during the febrile phase, severe headaches and joint pain can occur throughout the illness and are not specific indicators of the transition out of the febrile phase. Their presence does not correlate with the change in fever status that defervescence represents.