Dengue fever is an acute viral illness transmitted by mosquitoes that is characterized by sudden onset of headache, fever, severe joint and muscle pain, swollen glands, and rash. The presence of fever, rash, and headache, known as the "dengue triad", along with other symptoms like bleeding gums and pain behind the eyes, are indicative of dengue fever according to sources like MedicineNet.com.

1. SPECIALITY: INFECTIOUS DISEASE.
By Deepika Hamav.

2. Definition of Dengue fever:
An acute mosquito-borne viral illness of sudden
onset with headache, fever, prostration, sever joints
and muscle pain, swollen glands
(lymphadenopathy) , and rash.
The presence of fever, rash, and headache (“the
dengue triad”) is characteristic of dengue.
Other signs of dengue fever include bleeding
gums, severe pain behind the eyes and red palms
and soles.

11. REFERENCE.
1) MedicineNet.com
2) Google Images.