Aedes albopictus, or Asian tiger mosquito, is a small mosquito approximately 2-10mm in length with a striking black and white pattern. It is native to the tropical and subtropical areas of Southeast Asia although in the past couple of decades it has invaded many countries throughout the world, mostly as a consequence of the transport of goods as well as due to increasing international travel.
In fact, although these mosquitoes are native to tropical and subtropical regions they are successfully adapting themselves to cooler environments. In warm and humid tropical regions they are active throughout the year, whilst in temperate regions they hibernate during the winter. Eggs from strains in the temperate zones are more tolerant to the cold than ones from the warmer regions. They can even tolerate snow and temperatures under freezing. In addition, adult tiger mosquitoes can survive throughout winter in suitable microhabitats.
Mostly, Asian tiger mosquitoes spend the winter in the egg stage, hatching into larvae when the eggs are covered with water in the spring and summer. The larvae feed on small bits of debris and bacteria in the water. The male mosquitoes feed on plant juices and nectar and do not bite. On the other hand the female mosquitoes seek blood to help their eggs develop. They have a rapid bite that allows them to escape most attempts by people to swat them.
The mosquitoes will bite squirrels, dogs, deer and other animals, as well as people. Their blood meal is often broken off short without enough blood ingested for the development of their eggs. Therefore, Asian tiger mosquitoes bite multiple hosts during their development cycle of the egg making them particularly efficient at transmitting diseases. In fact they have been associated with the transmission of diseases such as West Nile Fever, Yellow Fever, St. Louis Encephalitis, Chikungunya Fever and Dengue Fever amongst others. To transmit infections the mosquitoes have to be carrying the pathogen within them first. Their bite is not particularly irritating to most people, but they are persistent biters.
About four or five days after feeding on blood the female lays her eggs just above the surface of the water, not on it, as other mosquitoes do. The surface is usually that of a hard-sided container such as a tree hole, a bucket or a tire. Any open container holding water will suffice for larval development, even with less than 30ml of water in. Since they have a short flight range (less than 200m) breeding sites are likely to be close to where this mosquito is found. Since this mosquito breeds in nearly any sort of water-filled container it often becomes very common and bothersome, even in neighbourhoods where there are normally few mosquitoes. The Asian tiger mosquito typically flies and feeds in the daytime, in addition to at dusk and dawn.
Aedes albopictus has proven to be very difficult to suppress or control due to their remarkable ability to adapt to various environments, their close contact with humans and their reproductive biology. The control of this mosquito begins with destroying the places where they lay their eggs which are never far from where people are being bitten.
How to prevent the mosquito from breeding
The control of this mosquito begins with destroying the places where they lay their eggs which are never far from where people are being bitten. Therefore:
- Remove any water-filled containers like old tires, food containers and buckets from your yard.
- Keep mosquitoes from breeding in bird baths, pet water dishes and paddling pools by emptying them at least once a week.
- Locate puddles that last more than three days, inlets to sewers and drainage systems holding stagnant water and drain them.
- Roof gutters should be kept clean of fallen leaves and other debris so that water does not collect in them.
- Flower pots, standing flower vases, knotholes and other crevices that can collect water should be filled with sand or fine gravel to prevent mosquitoes from laying eggs in them.
- Fish ponds should contain fish as these eat the mosquito larvae. The empty water would otherwise be an ideal breeding ground.
- Neighbourhood residents should work together to eliminate breeding sites like abandoned cars, old machinery and other junk in vacant areas. Litter can also hold rain water and should be removed.
- Report any piles of discarded tires or other accumulations of water-holding junk to local health officials.
- Any standing water in pools, catchment basins, etc, that cannot be drained or dumped can be periodically treated with properly labelled insecticides.
- Businesses should cover tires, store them indoors or treat them with an insecticide for control of mosquito larvae.
How to avoid getting bitten
It is not necessary to limit outdoor activities unless there is evidence of mosquito-borne disease in your area. However you can and should try to reduce the risk of being bitten by mosquitoes:
- Minimise the time spent outdoors between dusk and dawn when mosquitoes are most active (with regards to the Asian tiger mosquito, this is active even during the daytime)
- Be sure door and window screens fit tightly and are in good repair
- Wear socks, shoes, long trousers and a long-sleeved shirt when outdoors for long periods of time, and when mosquitoes are most active. Clothing should be light coloured and made of tightly woven materials to keep mosquitoes away from the skin
- Use mosquito netting when sleeping outdoors or in an unscreened structure, and to protect infants when outdoors.
- When it is necessary to be outdoors, apply insect repellent as indicated on the product’s label. The more DEET a product contains the longer the repellent can protect against bites. For most situations 10%-25% DEET is adequate and concentrations above 50% DEET do not increase the length of protection. Apply it to clothes when possible and sparingly to exposed skin if the label permits.
- Use fans - mosquitoes are weak fliers and a strong wind produced by a fan not only keeps them from flying but diffuses chemical cues they use to locate blood meals
Some precautions in brief
The precautions are as follows:
- This particular mosquito bites mainly during the day. Therefore do not go out without appropriate clothing covering as much of your body as possible in areas where this insect might be found.
- The commercial products that are available on the market which are effective against mosquitoes are usually also effective against this particular species.
- The best repellent products are those containing extracts from the DEET plant.
- Attach insect screens to windows and doors.
- Avoid sources for mosquito breeding sites in areas such as yards and gardens by removing containers, no matter how small they might be, which can carry water in them, eg. plant pots and buckets.
- Where it is necessary to keep water uncovered, eg. animal watering holes/bowls, ensure that this water is changed every two to three days.
- Empty swimming pools when these aren’t being used, especially if the water is not chlorinated.
- Keep suitable fish such as goldfish, gambuzja (guppy), buzaqq (killifish) in fish ponds.
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In Maltese
Taghrif dwar l-Aedes Albopictus.
Punti dwar l-Aedes Albopictus.
Kif tista tipprotegi lilek innifsek minn nemus u tevita li jbidu.