Archive | 2019
Dengue Virus and Aedes Mosquitoes: Ecological Relationship
Abstract
Human is infected by Dengue virus while female Aedes aegypti and Aedes albopictus mosquitos suck blood by biting. This is generally taken that Aedes aegypti as the primary particularly in urban and Aedes albopictus in the rural settings as secondary biological vector. Since, Aedes mosquitoes are found in tropical and sub-tropical countries, so not less than 128 countries have been facing the problems of dengue fever particularly during last 23 decades. Although, the survival period of adult Aedes mosquitoes ranges between 10 to 30 days, but usually it is considered as 21 days. Male partners undergo copulation with female once in life and then die. These female mosquitoes after copulation can store the whole population of ejaculated sperms in a safe and secured anatomical sac. From the storage the sperm comes to fertilize the eggs and thus male and female progeny are produced at a proportion of 50%. A female Aedes mosquito usually lays eggs 57 times in their life span and in each event, 80 to 250 fertilized eggs are produced. Thus, a female Aedes on an average give birth to not less than 500 new female mosquitoes. A total of 2 weeks’ period is needed for development and maturation of Aedes mosquito from egg to adult stage. In this way, mosquito population keep up their huge dynamic growth. Aedes mosquitoes need human blood for development, fertilization and maturation of eggs. So, female Aedes bite human beings based on a sensor maintained smell taking of human body’s different components, such as lipid, aromatic hydrocarbons and sweat salts. In each occasion of biting, a single female Aedes can bite even 15 to 20 persons at a time. Even this female can impose several bites to a single individual at a single event. The more the bites, more the consumption of human blood and more the production and laying of matures eggs. Interesting to know that these female mosquitoes move from behind while make attempt to bite. During their flight, they do not make any sound. The sites of biting they choose are usually the part of upper (below elbow to hand) and lower (below knee to whole foot) extremities of human body.