Dengue virus (DENV) is an arthropod-borne single stranded RNAvirus infecting around 100 million people every year and owes its complexitydue to its existence as distinct serotypes (DENV1, DENV2, DENV3 and DENV4).
Thegenome size of all DENV serotypes is approximately 11 kb consisting of 5′ UTR,a single polyprotein sequence which codes for three structural proteins and sevennon-structural proteins and a 3′ UTR. DENV infections increase health andeconomic burden mainly due to complications of this infection such as denguehaemorrhagic fever and dengue shock syndrome (2 & 3). These four viruses are calledserotypes because each has different interactions with the antibodies in humanblood serum. The four dengue viruses are similar — they share approximately 65%of their genomes — but even within a single serotype, there is some geneticvariation. Despite these variations, infection with each of the dengueserotypes results in the same disease and range of clinical symptoms.About threedays after feeding on blood, the mosquito lays her eggs inside a container justabove the water line. Eggs are laid over a period of several days, areresistant to desiccation and can survive for periods of six or more months.When rain floods the eggs with water, the larvae hatch.
The entire immature oraquatic cycle (from egg to adult) can occur in as little as 7-8 days. The lifespan for adult mosquitos is around three weeks. Aedes aegypti genome contains ?1376 million (1.
376billions) base pairs, which is about 5 times the size of the genome of themalaria vector Anopheles gambiae (12). The mosquitolarvae feed upon small aquatic organisms, algae and particles of plant andanimal material in water filled containers. The adult feed on nectar. On theother hand female need blood to produce eggs, and that is why female ofmosquito is responsible for the transmitting the viruses not the male.
Aedesaegypti is a small,dark mosquito with white lyre shaped markings and banded legs. This species ismost active for approximately two hours after sunrise and several hours beforesunset, but it can bite in well-lit areas. The mosquito bites humans, dogs, andother domestic animals, mostly mammals.
These mosquitos can use naturallocations or habitats; such as tree holes and plant axils, and artificialcontainers with water to lay their eggs. They lay eggs during the day in watercontaining organic materials (decaying leaves, algae, etc.) in containers withwide opening and prefer dark colored containers located in the shade.