The Asian Tiger Mosquito


The Asian tiger mosquito is a subspecies of the mosquitoes, which is at home in the tropical climate zones. Since the middle of the 20th century the Asian tiger mosquito can also be found in Europe. It is known to transmit various pathogens.

This transmission plays a role not only in humans but also in animals. Dengue fever and Chikungunya fever are among the diseases transmitted to humans. A role of the Asian tiger mosquito in the spread of the Zika virus is also discussed.

Where does the Asian tiger mosquito occur in Germany?

The Asian tiger mosquito is not originally at home in Germany. It usually lives in warmer climate zones. With the climate change, however, the weather in Germany is changing in such a way that the Asian tiger mosquito can also live with us.

The mosquito is almost exclusively brought in by trucks and other vehicles from the southern countries of Europe. That is why it can only be found along the major motorways. Several Asian tiger mosquitoes or their larvae and eggs were found at various resting places along the A5 in Baden-.

The mosquito could also be found in Freiburg and some other communities in Baden-. In Bavaria some of the animals were found in Nuremberg, others near Bamberg. Meanwhile the Asian tiger mosquito is spreading also in Hesse.

However, it remains to be said in general that very few of the animals have made their way to Germany so far. Still only isolated mosquitoes or their eggs are discovered. Furthermore, no pathogens were found in the mosquitoes examined in Germany.

Where does the Asian tiger mosquito occur in Switzerland?

The Asian tiger mosquito has probably penetrated into Switzerland via Italy and can therefore be found mainly in the south of the country. Canton Ticino is particularly affected by the mosquito’s colonization. The canton is located in the very south of Switzerland immediately north of Milan.

Eggs, larvae or adult Asian tiger mosquitoes have already been found in about 60 of the 115 municipalities of the canton. Similar to Germany, the tiger mosquito was mainly brought into the country via the traffic routes. In contrast to Italy, special measures are taken in Switzerland to prevent the mosquito species from spreading further.

This includes, for example, refraining from creating stagnant waters. Strictly implemented measures have prevented the uncontrolled spread of the tiger mosquito. Furthermore, no animals have been found in Switzerland to date that are actually infected with one of the dreaded diseases such as dengue fever or chikungunya fever.

Where does the Asian tiger mosquito occur in Italy?

The Asian tiger mosquito was not originally at home in Italy either. However, its occurrence has been known in Italy since the 1990s. It is suspected that the mosquito is carried over via transport routes from the USA.

In the meantime the tiger mosquito has spread over the entire Italian mainland. Especially the south is affected. Also in Sicily and Sardinia several animals of this species were found.

The Asian tiger mosquito spreads particularly fast in Italy, because it has no natural predators there. In addition, the government has not yet taken any concrete containment measures, such as reducing areas with stagnant waters or the widespread use of insect repellents. In Italy, the colonization by the Asian tiger mosquito is more threatening than in Switzerland or Germany, for example, because animals infected with the pathogen have already been found there.

They can thus transmit (life-) dangerous diseases such as dengue or Chikungunya fever. The bite of the Asian tiger mosquito initially looks like a classic mosquito bite. Usually a slight swelling is visible at the beginning, in addition a wheal can form at the bite.

Due to the reaction of the body against the saliva applied by the mosquito, local skin reactions occur. These are accompanied by a more marked swelling. In addition, the area reddens and may become warm or hot.

The inflammation may also cause pain. Every person reacts differently to an insect bite. Depending on how the body reacts, the swelling can be limited to the bite site or spread to an area the size of a hand.

The extent of the reaction also depends on whether the tiger mosquito was infected with a pathogen. The tendency is that the stronger the infection, the more the body’s reaction to the bite is evident. But also the bite of a blackfly or the Asian bush mosquito look similar.

The bite of the Asian tiger mosquito is much more painful compared to the mosquito generally known in Germany. There is swelling at the bite site. In addition, there may be an inflammatory reaction there, which is expressed by a reddening and overheating of the affected area.

The bite becomes problematic if the Asian tiger mosquito was previously infected with a pathogen. It can pick up this pathogen from the person it has bitten before and then pass it on to its next victim. Dengue fever or Chikungunya fever is typically transmitted by the mosquito.

Both diseases express themselves through particularly high fever. In addition, muscle and headaches, joint pain and possibly a skin rash occur. In rare cases, the pathogen can also settle in individual organs.

These are usually the liver, the heart or the meninges. In most cases, the infection of the organs leads to damage that is often irreversible. However, organ involvement is to be considered a rare complication.

Find out by which symptoms you recognize the bite of the Asian tiger mosquito. As with a classical mosquito bite, it can also come after a bite by the Asian tiger mosquito to a swelling in the affected area. The swelling is normally due to the fact that the body reacts to components of the mosquito saliva.

This saliva is brought into the human body by the tiger mosquito during the bite, as it acts as a blood thinner and the mosquito can therefore suck blood more easily. Typically, the reaction to a bite of the Asian tiger mosquito is stronger than to a normal mosquito bite, so that there is also a stronger swelling. If the bite is infected, the swelling increases, and there is also pain, redness and heating of the affected area.

As after the bite of a “normal” indigenous mosquito, the symptoms of an Asian tiger mosquito bite can last for several days. How long the itching is noticeable depends mainly on whether the bite is scratched. Pain, swelling and signs of inflammation will also disappear more quickly if the bite is not scratched.

In addition, the duration of the symptoms is determined by whether the mosquito has had enough time to fully inject its saliva. The strength of the body’s own defence reaction is also decisive. In general, the symptoms should not last longer than one week.

Of course, it can take longer if the bite causes an infection. The bite of an Asian tiger mosquito can become inflamed like any other mosquito bite. Since the mosquito injects a saliva secretion with the bite, which dilutes the blood, it comes to a defense reaction of the body.

Depending on how strongly the body reacts and how much secretion was injected, the reaction lasts longer or shorter. Many people also react allergic to the sting. An inflammation usually develops if the mosquito was previously infected with a pathogen.

The inflammation manifests itself through pain, swelling and redness of the affected area. Small local inflammatory reactions can usually be relieved by cooling. If the inflammation increases or spreads, a doctor should be consulted.

The prognosis after a bite of the Asian tiger mosquito is strongly dependent on whether complications occur and whether one is infected with a disease through the bite. The bite itself is harmless and usually disappears after some time without leaving any damage. If you are infected with Dengue or Chikungunya fever, the prognosis depends on the course of the disease. Both viruses can cause severe symptoms that disappear after a few weeks or months. In vulnerable groups (children, the elderly, immunocompromised persons) the disease can also be fatal.