Dengue Fever is caused by one of the four closely related, but antigenically distinct, virus serotypes Dengue type 1, Dengue type 2, Dengue type 3, and Dengue type 4 of the genus Flavivirus and Chikungunya virus. Infection with one of these serotype provides immunity to only that serotype of life, to a person living in a Dengue-endemic area can have more than one Dengue infection during their lifetime. Dengue fever through the four different Dengue serotypes are maintained in the cycle which involves humans and Aedes aegypti or Aedes albopictus mosquito through the transmission of the viruses to humans by the bite of an infected mosquito. The mosquito becomes infected with the Dengue virus when it bites a person who has Dengue and after a week it can transmit the virus while biting a healthy person. Dengue cannot be transmitted or directly spread from person to person. Aedes aegypti is the most common aedes specie which is a domestic, day-biting mosquito that prefers to feed on humans.
Intubation Period: Uncertain. Probably 6 days to 10 days
Period of Communicability: Unknown. Presumed to be on the 1st week of illness when virus is still present in the blood
Clinical Manifestations:
First 4 days:
>febrile or invasive stage --- starts abruptly as high fever, abdominal pain and headache; later flushing which may be accompanied by vomiting, conjunctival infection and epistaxis
4th to 7th day:
>toxic or hemorrhagic stage --- lowering of temperature, severe abdominal pain, vomiting and frequent bleeding from GIT in the form of melena; unstable BP, narrow pulse pressure and shock; death may occur; vasomotor collapse
7th to 10th day:
>convalescent or recovery stage --- generalized flushing with intervening areas of blanching appetite regained and blood pressure already stable
Mode of Transmission:
Dengue viruses are transmitted to humans through the infective bites of female Aedes mosquito. Mosquitoes generally acquire virus while