Convalescent phase: plasma leakage and hemorrhage resolve, vital signs stabilize, and accumulated fluids are resorbed. An additional rash (a confluent, erythematous eruption with small islands of unaffected skin that is often pruritic) may appear during the convalescent phase (within one to two days of defervescence and lasting one to five days)

Febrile phase: sudden high-grade fever (≥38.5°C) accompanied by headache (sometimes with eye pain), vomiting, myalgia, arthralgia, and a transient macular rash in some cases.

Critical phase: Around the time of defervescence (typically days 3 to 7 of infection), a small proportion of patients (typically children and young adults) develop a systemic vascular leak syndrome characterized by plasma leakage, bleeding, shock, and organ impairment [36]. The critical phase lasts for 24 to 48 hours.

Period of remission: asting up to 48 hours may follow the period of infection, characterized by the abatement of fever and symptoms

Period of intoxication: begins on the third to sixth day after the onset of infection with return of fever, prostration, nausea, vomiting, epigastric pain, jaundice, oliguria, and hemorrhagic diathesis. The viremia disappears at this stage and antibodies appear in the blood

Period of infection: viremia, which lasts for three to four days. The patient is febrile and complains of generalized malaise, headache, photophobia, lumbosacral pain, pain in the lower extremities, myalgia, anorexia, nausea, vomiting, restlessness, irritability, and dizziness