Infections by Asian mosquito in Germany

Pathogen: Asian mosquito native to Germany

06/16/2014

Numerous infectious diseases are transmitted by mosquitoes. With each trick, the little bloodsuckers can transmit dangerous pathogens. In a new safety laboratory, experts now want to investigate the danger posed by immigrant mosquitoes.

Domestic house mosquito has got competition from Asia
The common house mosquito Culex pipiens, which is located here, has meanwhile got competition from Asia. The insect researcher Helge Kampen from the Friedrich Loeffler Institute (FLI) on the Baltic island of Riems explained according to a news agency dpa: "The Asian bush mosquito has now established itself in Germany. We are sure that she is wintering here. "The FLI is the federal research institute for animal health. The Asian bush mosquito was first discovered in southern Germany in 2008, later mainly in Lower Saxony and North Rhine-Westphalia and this year, the FLI scientists were able to prove the insect in North Rhine-Westphalia.

Researchers want to breed exotic mosquitoes in a new safety laboratory
Aedes japonicus, as the Asiatic bush mosquito is called in Latin, was the first exotic mosquito species among the 50 native species to be included in the catalog of mosquitoes that live in Germany. "The fight against the bush mosquito makes no sense, it has spread too far in Germany," says Kampen. The scientists of the FLI now take a closer look at both exotic and domestic mosquito species in a new safety laboratory. Two months ago, the entomologists started the first breeding experiments of the exotics in the "Insektarium" secured by airlocks. Male and female bush mosquitoes should first meet for fertilization in gauze-covered boxes and in ideal conditions with at least 70 percent humidity and 24 degrees room temperature. Since mosquitoes in the wild form copulation swarms, this is not easy. However, if the breed succeeds, the biologists and insect researchers want to start the first infection attempts at the end of 2014, in order to explore the transfer potential.

Carriers of exotic infectious diseases
The Aedes japonicus is one of carriers of dangerous infectious diseases. For example, the mosquito with its curly pattern on the legs may transmit diseases that are not occurring in this country, such as West Nile fever, dengue fever or chikungunya fever. All these diseases are dangerous for humans and can sometimes be fatal. Chikungunya fever is usually not fatal. In addition to the fever and muscle or limb pain, it can also lead to symptoms such as lymphadenopathy, itchy rash, mucosal bleeding or gastrointestinal complaints.

West Nile diseases in Greece
West Nile fever is a zoonosis, which means that the virus can be mosquito-borne from an infected animal to humans. Infected people usually suffer from headaches and body aches, often accompanied by vomiting and diarrhea. West Nile diseases are also found in Greece; several patients already died. More and more of the exotic mosquitoes are invading Central Europe with climate change and globalized trade. "Even the aggressive Asian tiger mosquito has already been sighted in Germany. For the researchers, it is only a matter of time until they establish themselves as well as the Asian bush mosquito in this country. "

Domestic mosquitoes could transmit further diseases in the future
However, domestic mosquito species could also be carriers of unknown pathogens in the face of warmer temperatures, says Stefanie Becker, director of the FLI Institute for Infection Medicine. "Every virus has a temperature range, under which it develops particularly well." That mosquitoes transmit diseases, speak for the smoothness of some pathogens. "It is clever of the virus to have an intermediate host with the mosquitoes, who does not become ill himself," said Becker. Viruses transmitted to humans by domestic mosquitoes, such as the Sindbis virus, the Tahyna virus or the Batai virus, have existed in Europe for a long time. In general, the infections are not severe and are usually associated with mild symptoms of summer flu.

Dangerous pathogens for humans and animals
"After the eradication of malaria in Germany also disappeared the interest in mosquito research - until 2006 on the bluetongue thousands of cattle and sheep died," said the head of the Federal Research Institute, Thomas C. Mettenleiter. The economic damage caused by the disease is estimated at 200 million euros in Germany alone. Above all, such exotic, mosquito-borne pathogens that can be dangerous in addition to humans and livestock such as cattle, sheep, horses or poultry, move for the animal diseases researchers on the island Riems in the view. These include, among others, "the Rift Valley fever virus or the Japanese Encephalitis virus". The Africa-based Rifttal fever virus can be transmitted by various types of mosquitoes. As Becker reported, it has since penetrated from Kenya to the Arabian Peninsula. And the Usutu virus, originally native to Africa, where blackbirds also died in Germany, is transmitted by mosquitoes. (Ad)