Overlapping signs like fever can manifest differently, depending on whether it is a sign of dengue or COVID-19.
The fever recorded during COVID-19 is usually said to be low or moderate grade. This can usually be managed at home with doctor prescribed medicines and ample rest, healthy diet and hydration. On the other hand, in case of a dengue infection, fever can rise considerably high which may require immediate medical attention.
Further, the fever seen with a dengue infection is usually continuous and persistent. Whereas with COVID-19, the fever can come and go.