The mild winter is followed by the mosquito plague

Spread of exotic mosquito species favored by mild temperatures

02/20/2014

The unusually mild winter, which has already been declared over, means that a veritable mosquito plague is to be expected in the coming year, explained Professor Sven Klimpel from the Senckenberg Gesellschaft für Naturforschung to the news agency „dpa“. Also, the increased spread of exotic mosquito species, such as the Asian bush mosquito or the Asian tiger mosquito, is favored by such a mild winter.

According to the expert, the exotic species of mosquitoes can spread further and further north in the face of general climate changes and the disappearance of pronounced seasons. A mild winter is very accommodating, said the Senckenberg researcher. However, the domestic mosquitoes also benefit from the mild weather. Experts expect a veritable mosquito infestation for the coming year. As soon as the temperatures reach well over ten degrees Celsius for a few days, the development in the overwintered mosquito eggs begins, explained Professor Klimpel. Then the larvae hatch, which live and grow in the water. Although, according to the expert, no larvae have yet been found, temperatures should remain so mild, „then it could also quickly lead to a local, increased occurrence of mosquitoes.“

Exotic mosquito species favor spread of infectious diseases
The increasing prevalence of exotic mosquito species also increases the risk of disease spread in Germany, such as West Nile fever or dengue fever. The mosquitoes are ideal carriers of such viruses, explained Professor Klimpel. They are attributed a so-called vector competence here. After the mosquitoes have taken the blood of infected humans or animals, they can deliver the pathogens with their saliva into the wound with the next trick. Therefore, the growing prevalence of exotic mosquito species is being considered with concern by the experts. For example, independent populations of the Asian bush mosquito, which also winter here, have now been detected in Baden-Württemberg, Hesse and North Rhine-Westphalia. The Asian tiger mosquito has already been discovered several times in southern Germany, but according to Professor Klimpel, these were not yet independent populations. Both species of mosquitoes will be in the future, however „spread in Europe and continue to move north“, stressed the Klimpel opposite the „dpa“.

Mosquito monitoring for risk assessment
The Senckenberg Society for Natural Science reports that mosquitoes „Globally considered the most important vectors vector-associated infectious agents“ be valid. In Germany are estimated „around 49 different mosquito species native.“ At least some of them are potential carriers of diseases that have not previously been found in Germany. Here you go „increasingly discussed the possibility of transmission of arboviruses, such as West Nile, Tahyna or Sindbis virus, but also the transmission of certain worms (Dirofilaria) and explored“, writes the Senckenberg Society for Natural Science. In order to be able to assess the risks better, a so-called mosquito monitoring, the spread of the mosquito species in one „Mosquito card for Germany“ detected. The joint project will be headed by Professor dr. Sven Klimpel, including scientists from the Bernhard Nocht Institute for Tropical Medicine in Hamburg (BNI), the Senckenberg German Entomological Institute (SDEI) and the KABS (Community Action Group to combat snoring plague) involved. The monitoring makes it possible to detect changes in the native mosquito fauna and to recognize them early. By accompanying laboratory experiments will also be clarified, „to what extent domestic species are able to transmit certain pathogens under the given conditions (vector competence)“, reports the Senckenberg Society for Natural Science. (Fp)

Picture: Frank Hollenbach