Dengue is a vector-borne disease transmitted by the bite of an infected female Aedes Aegypti mosquito.
The mosquito becomes infected when it feeds on the blood of a person infected with the virus. After about one week, the mosquito can then transmit the virus while biting a healthy person.
There are 4 serotypes of the virus that causes dengue. These are known as DEN-1, DEN-2, DEN-3, DEN-4.
Infection with one strain will provide life-time protection only against that particular strain. However, it is still possible to become infected by other strains and develop into severe dengue.
Dengue cannot be spread directly from person to person. However, a person infected and suffering from dengue fever can infect other mosquitoes.
Most cases occur in tropical areas of the world, including the Indian subcontinent, Southeast Asia, Southern China, Taiwan, the Pacific Islands, the Caribbean, Mexico, Africa, Central and South America.
Dengue causes flu-like symptoms and lasts for 2-7 days. Dengue fever usually occurs after an incubation period of 4-10 days after the bite of the infected mosquito.
High Fever (40°C/ 104°F) is usually accompanied by at least two of the following symptoms: headaches, pain behind eyes, nausea, vomiting, swollen glands, joint, bone or muscle pains and rash.
There is no vaccine or specific medication for dengue fever. Patients should seek medical advice, rest and drink plenty of fluids.
As a precautionary approach, patients can adopt measures to reduce transmission by sleeping under a treated net especially during the period of illness with fever.
Aedes aegypti is a daytime feeder. The peak biting periods are early in the morning and in the evening before dusk.
Aedes aegypti has evolved into an intermittent biter and prefers to bite more than one person during the feeding period. This mechanism has made Aedes aegypti a very highly efficient epidemic vector mosquit
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