Over the last few decades, there has been an increase in the occurrence of alien species of mosquitoes in Europe. Gels are brought passively into new areas, primarily through the global transport of goods, and if suitable climatic conditions are found there, new populations can establish themselves in these areas. Non-native gelatinous species can be "invasive species" if they are shown to lead to changes in the structure and composition of ecosystems and have a detrimental effect on ecosystem services, the human economy and well-being. In the case of alien mosquitoes, there is a particular risk that these species could also spread exotic pathogens.

Reports of alien mosquito species from the public can be essential to quickly detect new populations of these species. Citizen science projects are therefore a valuable addition to monitoring projects carried out by experts. The "Mosquito Alert" app was developed to offer citizens a tool to easily report possible tiger mosquitoes. This app, which is available throughout Europe, was developed as part of the EU AIM-COST project and is coordinated by AGES in Austria. Users can anonymously upload photos of mosquitoes via the app, which are then scrutinised by several experts. The result is then reported to the user and is also publicly accessible on the project's website. This project not only enables information on the distribution of alien mosquito species to be recorded, but also raises awareness among users about the health risks posed by mosquitoes.

In 2024, a significant increase in reports was achieved compared to the previous year. It can be seen that the app is primarily used in areas where the tiger mosquito has already established populations (Vienna and Graz/Styria). The app has also been used frequently in Lower Austria and Upper Austria, although there have been significantly fewer detections of tiger mosquitoes here compared to Vienna and Styria.
In Vienna, Graz and Linz, where tiger mosquitoes are already known to occur from previous years, the reports from the "Mosquito Alert" app show an increase and significant spread of the tiger mosquito population compared to the previous year 2023.