Asian tiger mosquitoes (Aedes albopictus or Stegomyia albopicta) are widespread throughout the tropical and subtropical regions of the world, partly also in the Mediterranean area. Tiger mosquitoes are considered vectors for diseases like chikungunya fever, dengue fever, and Zika.
The Asian tiger mosquito is originally from Southeast Asia. In the last 30 years it has invaded many countries around the world including various regions in the Americas and the Mediterranean. In North America they adapted to the colder climate so that they now can be found as far north as the Great Lakes region. A primary reason for the wide distribution is that the Asian tiger mosquito moves easily in shipments of plants and used tires across the world.
Distribution of Aedes albopictus
A detailed distribution of the Asian tiger mosquitoes in Europe (as of October, 2016) is shown on the right side. The map shows the current known distribution of Aedes albopictus in Europe at ‘regional’ administrative level (NUTS3). The map is provided and was developed by ECDC/VBORNET (European Centre for Desease Prevention and Control), and is based only on confirmed data (published and unpublished) provided by experts from the respective countries as part of the VectorNet project.
An estimated range of the Asia tiger mosquitoes in the United States, 2016, is shown on the right, provided by the CDC (Centers of Disease Control and Prevention). Maps have been updated from a variety of sources. This map represent CDC’s best estimate of the potential range of Aedes albopictus in the United States. Maps are not meant to represent risk for spread of disease. More information on the CDC webpage >
The dark-colored Asian tiger mosquito is about 3-10 mm long. A single silvery-white line that begins on the head and continues down the dorsal side of the thorax is the surest characteristic marking to identify the Asian tiger mosquito. A further striking feature is the white markings on the legs.
Unlike most other mosquitoes, Aedes albopictus is a day biter and unusually aggressive. This is why it has become a major pest in many communities. Female tiger mosquitoes normally lay their eggs in natural or artificial containers filled with water. Flower pots, vases, buckets, water barrels, discarded tires, rain gutters, or even discarded cups with water in them are used as breeding sites. Their eggs are tolerant to periods of drought, making the Asian tiger mosquito perfectly adapted to the urban environment.
The life cycle of tiger mosquitoes
The life cycles of the Asian tiger mosquito and the yellow fever mosquito are very similar. The eggs are resistant to heat and dryness, and are deposited in natural and artificial containers subject to flooding. When eggs are covered by water, the larvae hatch, hang at the surface of the water, and breathe through a snorkel-like siphon at the tip of the abdomen. There are four larval stages that feed on organic material that they filter out of the water with their mouthparts. The fourth-stage larva changes into a pupa that hangs at the surface of the water and breathes air through two snorkel-like siphons at the front end. The pupa is a non-feeding stage where the mosquito changes from the larval form into an adult insect or imago. The adult mosquito emerges from the pupa and normally feeds on sweet plant juices and nectar to meet their energy requirement. Only female mosquitoes feed on blood, which they need to produce their eggs.
What diseases do the Asian tiger mosquitoes transmit?
Asian tiger mosquitoes are considered an important transmitting organism, or vector, of a disease called chikungunya fever. They can also transmit the disease dengue fever and Zika fever . The Asian tiger mosquito bites humans, as well as birds and other animals. This is why scientists consider it a potential bridge vector, meaning that it may pick up disease agents from animals, and transmit them to humans.