Vector-Dengue,Chikungunya and Zika

Diseases caused by Dengue,Chikungunya and Zika viruses is mainly transmitted by two species of mosquitoes, Ae. aegypti and Ae. albopictus, former is a primary vector for transmitting dengue disease world-wide, while the later is a secondary vector.    
Aedes aegypti (Linnaeus, 1762)
Yellow Fever Mosquito
Aedes albopictus (Skuse, 1895)
Asian Tiger Mosquito
Subspecies &Geographical Distribution
  • Aedes aegypti formosus (Walker): Presumed ancestral form and its distribution is restricted to sub-Saharan Africa.
  • Aedes aegypti aegypti (Haung): Originated in Africa and has spread globally in tropical and subtropical regions. Is believed to have evolved from Aedes aegypti formosus.
Indigenous to South-east Asia, islands of the Western Pacific and Indian Ocean and expanded to temperate and tropical regions globally.
  Geographical overlapping only in East Africa
Morphological distinction Aedes aegypti is a small, dark mosquito with white lyre shaped markings and banded legs. Aedes albopictus is a small, dark mosquito with a white dorsal stripe and banded legs.
Life cycle
  • Developmental phase consists of four stages; egg, larva, pupa & adult.
  • Eggs have the ability to withstand desiccation for a long dry period (>6 months), allowing eggs to be easily spread to new locations. Incubation period is <48 hours.
  • Immature aquatic developmental period (i.e., from egg to adult) varies between 8 to 10 days.
  • Adult life span in the environment is around two to three weeks.
Feeding Male and female adults feed on nectar/juice of plants; however female mosquitoes need blood meal in order to produce eggs.
  • Crepuscular: Is active and bite during dusk and dawn.
  • Anthropophagic: Prefers to bite humans.
  • Endophagic: Prefers to feed indoors.
  • Endophilic: Prefers to rest outdoors in cool damp spots.
  • Aggressive biter: This mosquito has a rapid bite that allows it to escape most attempts by people to swat it.
  • Feeds during day time as well as at dusk and dawn.
  • They have a wide host range and feed on mammals besides humans and also on birds.
  • Exophagic: Generally prefers to feed outdoors.
  • Exophilic: Prefers to rest outdoors.
Breeding places Artificial or natural water containers: Breeds around human dwellings in water storage containers, flower pots, plates under potted plants, discarded tires, cemetery vases, discarded tin cans, ornamental fountains, drums, water bowls for pets, birdbaths, tree holes, plant axils etc. Prefers to breed in tree holes, plant axils, tyres, rock holes, hollow bamboo stumps etc. Also breeds in water storage containers, flower pots, other artificial containers etc.
Vector capacity Primary vector of dengue in India & world-wide, and also a potential vector for chikungunya & yellow fever. Secondary vector for dengue disease and also well known for transmitting chikungunya and West Nile Virus.
Flight range Flight range is (<200 to 400 m.) and therefore egg production sites are likely to be close to where they are found.

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