Aedes aegypti

Stegomyia aegypti, a man stabbing. Characteristic of the lyre- shaped drawing on the thorax.

The yellow fever mosquito or Egyptian tiger mosquito ( Stegomyia aegypti, formerly Aedes aegypti ) is a of mosquito of the tropics and subtropics. It is the principal transmitter of dengue fever, yellow fever and some other viral diseases.

Dissemination

Originally probably native to Africa, the yellow fever mosquito was kidnapped by the people in other parts of the world. She is now widespread in the tropics and subtropics worldwide.

Description and life

The yellow fever mosquito is a small (3-4 mm), dark colored mosquito with white stripes on the legs and a white drawing on the neck plate ( scutum ), reminiscent of a lyre. The proboscis is black.

Females and males are equal drawn, mostly the females are slightly larger. In addition, (typical of mosquitoes ), the antennae of the males bushy. As members of the subfamily of Culicinae the palps of the males are to be longer than the proboscis, while they are significantly shorter in females.

Only the female mosquitoes suck blood after fertilization, to meet their protein requirements for the production of offspring. The male mosquitoes feed mainly on nectar and other sweet plant juices. The females can it meet its energy requirements.

Yellow fever mosquitoes are well adapted to survival in human environment. Preferred host is the man who on occasion but also other available vertebrates being stung. Stab you at any time of day, with a clear preference but in the twilight.

Life cycle

Are sufficient for oviposition of the yellow fever mosquito smallest amounts of standing water, as they accumulate in tanks, bottles or stored tires. They can be of signal compounds (referred to as kairomones ) as nonanoic and octanoic acid, 2 -nonanol and their methyl esters, which are produced by aquatic microbes attract.

The larva develops in the water, where they molt four times and eventually pupates. The pupa is also aquatic, portable and takes about two days for their development. The entire life cycle takes under optimal conditions ten days but may be extended in cold weather to several months.

Stock Status

Yellow fever mosquitoes are in addition to other mosquito species as Diceromyia Furcifer, Stegomyia albopictus and Stegomyia bromeliae as the main vectors of yellow fever virus in the urban cycle and the viral pathogen of dengue fever, Chikungunya fever, the Rift Valley fever and other tropical viral diseases. As carriers of Japanese Encephalitis the yellow fever mosquito is probably out of the question.

Genome

The genome of the yellow fever mosquito Stegomyia aegypti was completely sequenced in 2007 and in the meantime, the number of genes known to stabilize. The genetic information is in three chromosomes. The genome consists of a total of 1,376,422,251 base pairs and 16.047 genes. Almost half of the genome is in DNA transposons.

Reduction strategies

The British company Oxitec resulted in the fall of 2009 the first experimental release of genetically modified ( transgenic ) yellow fever mosquitoes on Grand Cayman. The strategy consists in the release of transgenic males die their descendants already in the larval or pupal stage, which populations can be reduced. In the field trial, the population decreased by 80%. Luke Alphey, the scientific director of the company, had developed the transgenic mosquitoes in the 1990s at the University of Oxford. The Gates Foundation is cooperating with its malaria program with Oxitec. Further field trials were conducted in December 2010 in Malaysia and since 2011 also in Brazil.

In an alternative approach, parallel testing to a research team at the University of Cairns, Australia, since 2011 the mass suspension of males who are infected with the transmissible to the females Wolbachia bacterium that has the ability to own infection with the dengue virus, and thus the transfer prevented in humans.

Traditional methods for the control of yellow fever mosquitoes are attempts of killing by smoking in residential areas, as well as the broad-based observation and, where appropriate chemical treatment of potential breeding sites in water tanks, puddles and other stagnant water accumulations.

Systematics and Taxonomy

Stegomyia has long been a sub-species of the genus Aedes. In 2004, this subgenus was raised to genus. In many human and veterinary medical works but still the former name Aedes aegypti Stegomyia aegypti is used instead.