Monitoring of alien mosquitoes in Western Austria (Tyrol, Austria, 2018)

Author summary The importance of mosquitoes for Public Health in Europe increased dramatically with the introduction of alien species considered to be competent vectors of important human pathogens (e.g. dengue, chikungunya, and Zika viruses), which autochthonous mosquitoes are not yet known to transmit. The Asian tiger mosquito (Aedes albopictus), the Asian bush mosquito (Aedes japonicus), andAedes koreicusare particularly of relevance, as they are expanding their range in Europe. Tyrol, a region in the Alps with main transport routes from Italy to Germany is of high relevance for the spread of potential invasive, alienAedesmosquitoes. In this study, we demonstrate highways to be points of entry, and point to possible establishment of the Asian tiger mosquito and the East Asian bush mosquito in Tyrol (findings at highways and urban areas). Moreover, we report the first findings ofAe.koreicusin Austria, this species having most probably spread from neighbouring populations in Italy. Mosquitoes are of major importance to human and animal health due to their ability to transmit various pathogens. In Europe the role of mosquitoes in public health has increased with the introduction of alienAedesmosquitoes such as the Asian tiger mosquito,Aedes albopictus; the Asian bush mosquito,Ae.japonicus; andAe.koreicus. In Austria,Ae.japonicushas established populations in various regions of the country.Aedes albopictusis not known to overwinter in Austria, although isolated findings of eggs and adult female mosquitoes have been previously reported, especially in Tyrol.Aedes koreicushad not so far been found in Austria. Within the framework of an alien mosquito surveillance program in the Austrian province of Tyrol, ovitraps were set up weekly from May to October, 2018, at 67 sites- 17 in East Tyrol and 50 in North Tyrol. Sampling was performed at highways and at urban and rural areas. DNA obtained from mosquito eggs was barcoded using molecular techniques and sequences were analysed to species level. Eggs of alienAedesspecies were found at 18 out of 67 sites (27%). BothAe.albopictusandAe.japonicuswere documented at highways and urban areas in both East and North Tyrol.Aedes koreicuswas found in East Tyrol. During this mosquito surveillance program, eggs ofAe.albopictus,Ae.japonicus, andAe.koreicuswere documented in the Austrian province of Tyrol. These findings not only show highways to be points of entry, but also point to possible establishment processes ofAe.japonicusin Tyrol. Moreover,Ae.koreicuswas documented in Austria for the first time.