Infectious, disabling mosquito-borne fever. Other symptoms include extreme joint pain and stiffness, intense pain behind the eyes, a return of fever after brief pause, and a characteristic rash. Dengue is caused by a virus carried by mosquitoes of the genus Aedes, usually A. aegypti, which also carries yellow fever. There are four strains of virus; infection with one type does not confer immunity to the remaining three. Treatment focuses on relieving symptoms. Patients should be isolated during the first three days, when mosquitoes can pick up the disease from them. Prevention relies on mosquito control.

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