Scientific classification of Aedes Mosquitoes:
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Diptera
Family: Culicidae
Tribe: Aedini
Genus: Aedes Meigen,1818.

Aedes is a genus of mosquitoes contains more than 700 species globally. Though this genus originally found in tropical and subtropical zones, now found on all continents except Antarctica. Some species of this genus transmit serious diseases (EWO 2020). More specifically Aedes aegypti : Bites humans, carries Dengue fever,Chikungunya, Heartworm, Murray Valley encephalitis, Ross River virus, West Nile virus, Yellow fever, Zika virus; Ae. albopictus : Bites humans, carries Cache Valley virus, Chikungunya, Dengue fever, Eastern equine encephalitisWest Nile virus, Yellow fever, Zika virusAe.atropalpus /Ae. atropalpos : Bites humans, carries La Crosse virus, Plasmodium gallinaceum, St. Louis encephalitis, West Nile virus,Ae. cantator : Bites humans, carries Eastern equine encephalitis, Jamestown Canyon virus, West Nile virus,Ae. cinereus : Bites humans, carries Bunyamwere virus, California encephalitis virus, Eastern equine encephalitis, Jamestown Canyon virus, Sindbis virus, West Nile virusAe.fulvus : Bites humans, carries Venezuelan equine encephalitis virus, West Nile virus,Ae. hesperonotius : Carries Heartworm, La Crosse virusPlasmodium gallinaceum, Ae.infirmatus : Bites humans, carries California encephalitis virus, Keystone virus, Trivittatus virus,West Nile virus, Western equine encephalitis; Ae. melanimon : Bites humans, carries California encephalitis virusWest Nile virus,Western equine encephalitis (EWO 2019); Ae. polynesiensis : vector of DengueRoss River virus and lymphatic filariasis, and a probable vector of Zika virus (WAP 2019).
Dramatically, within the last 2 decades the world has seen the emergence and dramatic spread of Aedes-transmitted arboviral diseases. Social, environmental, and demographic changes assist the proliferation of existing transmission systems and the spread of viruses and vectors into new ecological settings (Roiz et al. 2018).
Generally,  female Ae. aegypti (Yellow Fever mosquito ) spends their lifetime in or around the houses where they emerge as adults and are capable of biting anyone throughout the day and they usually fly an average of 400 metres. On the contrary, Ae. Albopictus (the Asian Tiger mosquito) is basically a forest species that has become adapted to rural, suburban and urban human environments. The eggs can withstand very dry conditions (desiccation) and remain viable for many months in the absence of water.
Dengue and Chikungunya diseases are caused by viruses, Flavivirus (Flavirideae) and  Alphavirus (Togaviridae) respectively. Viruses are maintained in nature by mosquito-vertebrate-mosquito cycles (Schmaljohn and McClain 1996.). Dengue is much more common and more fatal than Chikungunya. Though Dengue and Chikungunya diseases show very similar symptoms. Especially in Chikungunya, joint pain may last for years causing long term quality of life issues. Within the mosquito, the virus infects the mosquito mid-gut and subsequently spreads to the salivary glands over a period of 8-12 days. After this incubation period, the virus can be transmitted to humans during subsequent probing or feeding (WHO 2020).
In Bangladesh, Huda (2000) reported that out of 26 species of Genus Aedes only Ae. aegypti and Ae. albopictus are responsible for dengue fever. In April 2014, the author of this article collected Ae. albopictus from Chittagong university campus, and on September 2017, that species was confirmed through DNA technique at the Centre for Biodiversity Genomics, University of Guelph, Canada.
Dengue fever was unknown in Bangladesh until an outbreak occurred in 1964, known as "Dacca fever" (Aziz et al. 1967). Mutsuddy et al. (2019) reported that between 2000 and 2017 presented that 49.73% of the dengue cases occurred during the monsoon season (May–August) and 49.22% during the post-monsoon season (September–December). But, in 2014 dengue occured during the pre-monsoon season. During 2015–2017, in the pre-monsoon season, the dengue cases were reported to be more than seven times higher compared to the previous 14 years due to the presence of high density of larva and pupa of the dengue vectors in the environment all the year round, and average rainfall, humidity and temperature is responsible for that situation.
In 2018, dengue killed 26 and affected 10,148 people. In chikungunya, it was found the first case in 2008, and outbreak for the first time in Bangladesh during 2017. The proximity of Aedes mosquito breeding sites to human habitation is a significant risk factor for dengue and chikungunya diseases.

LIFE CYCLE:  The Aedes mosquitoes have four life stages such as (1) egg, (2) larva, (3) pupa and (4) adult. From an egg to an adult, takes approximately 9-12 days depending on the environmental factors especially temperature. 
Eggs are laid 50 to 300 eggs at one time on a moist surface. Eggs float separately and forming a raft in just a few centimeters of water. Most eggs hatch into larvae within 48 hours if submerged in water. The larvae grow and develop through four instars before developing into pupae. In this stage there is a tubular respiratory siphon on 9th abdominal segment. In pupal stage, dorsal respiratory tube is narrow and elongated. This process takes 4-5 days. Adult mosquitoes then emerge from the pupae after about 48 hrs. Adult sits more or less parallel to the substratum. Noticeable black and white markings on their bodies and legs. Wings are large and thick and are provided with black and white bands. Hairs are dense and coarse on antennae.

PRECAUTIONS: The following precautions have been modified from the articles of Becker et al. (2010) and NST (2014).
Source reduction strategy:  It is also called environmental management strategy is to eliminate unnecessarily container habitats that collect water (such as flower vases, plastic jars, bottles, cans, tires, buckets, construction sites etc.) in which Aedes mosquitoes can lay their eggs.
Personal protection: By using windows and door screens or by keeping their doors and windows closed. Wearing long pants and long-sleeved shirts can reduce mosquito bites when spending time outdoors. Mosquito repellents can be applied to exposed skin and clothing to lower the risk of mosquito bites. Repellents that contain DEET, picaridin, lemon eucalyptus oil, or IR3535 as the active ingredient. Sleeping under a mosquito net can also provide protection from being bitten, particularly in areas where people rest in the afternoon or in houses with infants. The electric mosquito racket is another effective Aedes mosquitoes killing instrument.
Chemical Control: Insecticides can be used to kill mosquito larvae or adult mosquitoes. However, insecticides are expensive, and high doses can be toxic to humans and other species.
Oil drip: The thin layer of oil on top of the water prevents mosquito breeding in two ways: mosquito larvae in the water cannot penetrate the oil film with their breathing tube, and so drown and die; also adult mosquitoes do not lay eggs on the oiled water.
Nuclear Sterile Insect Technique: Sterilized male mosquitoes, which are then released to mate with females in the wild. As these do not produce any offspring, the insect population declines over time.
Bioinsecticides: A bioinsecticide is Bacillus thuringiensis israelensis (Bti), which is a naturally occurring soil bacterium that can effectively kill mosquito larvae present in water.
Biological Control: Predatory crustaceans like copepods, nymph or larva of aquatic insects, the nymph of Dragonflies, the larval stage of Biting Midge (Corethrella appendiculata), Elephant mosquito (Toxorhynchites spp.) and many varieties of fish, including mosquito fish (Toxorhynchites spp.) and many varieties of fish, including mosquitofish (Gambusia affinis) and goldfish eat mosquito larvae. 
Social mobilization:  Community participation and health education programs can assist to reduce Aedes mosquito populations and Aedes-borne diseases as well.
Supporting activities: Capacity building, advocacy, policies and laws, and research and innovation.
Like the previous year, authority should take attempt to eradicate mosquitoes and prevent mosquito-borne diseases especially Chikungunya and dengue, to continue awareness program, to establish emergency medical facilities immediately. Besides, a year- round research program is needed to improve the environment friend techniques for mosquito and mosquito-borne disease control.

Aziz, M.A., Gorham, J.R. and Gregg, M.B., 1967. Dacca fever. an outbreak of dengue. Pak J Med Res6, pp.83-92.
Becker, N., Petric, D., Zgomba, M., Boase, C., Madon, M., Dahl, C. and Kaiser, A., 2010. Mosquitoes and their control. Springer Science & Business Media.
EWO 2019.
EWO 2020.
Huda K.M.N.  2000 (August 14) Dengue mosquitoes. The daily Azadi.
Mutsuddy, P., Tahmina Jhora, S., Shamsuzzaman, A.K.M., Kaisar, S.M. and Khan, M.N.A., 2019. Dengue situation in Bangladesh: An epidemiological shift in terms of morbidity and mortality. Canadian Journal of Infectious Diseases and Medical Microbiology2019.
NST 2014.
Roiz, D., Wilson, A.L., Scott, T.W., Fonseca, D.M., Jourdain, F., Müller, P., Velayudhan, R. and Corbel, V., 2018. Integrated Aedes management for the control of Aedes-borne diseases. PLoS neglected tropical diseases12(12): e0006845.
Schmaljohn, A.L. and McClain, D., 1996. Alphaviruses (togaviridae) and flaviviruses (flavivir idae). In Medical Microbiology. 4th edition. University of Texas Medical Branch at Galveston.
WAP 2019.
WHO 2020.

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