Poster, Jahrestreffen des AK Biogeographie im Verband der Geographen an Deutschen Hochschulen (VGDH), Trier: 07.05.2010 - 09.05.2010
Invasive aedine mosquito species are of medical importance in Europe and elsewhere, due to their vector competence for several infectious diseases. Beside biological and genetic factors in the transmission cycle of arborviruses as virus load above threshold and presence of non immune hosts, several ecological components determine the process. Besides the direct environmental effects on vector-borne diseases, climate change in particular alters thermal and hydrological conditions throughout Europe and will influence the single organisms which constitute a chain of infection: pathogen, vector and host distribution. Aedes albopictus is in a rapid extension of its dispersal area: originally native in South-East Asia, it became a “global player” during the last decades. This potential vector of various infectious diseases (e.g. Chikungunya, Dengue and West-Nile) is listed as one of the 100 “Worlds Worst Invaders”. Besides climate change this spread is strongly driven by human activities, such as transport, travelling and increased connectivity of potential habitats across regions. Introductions happen by chance, but the establishment of viable populations depends on climatic and further environmental habitat restrictions respectively. The establishment and adjacent dispersal of Ae. albopictus in Northern America (since 1985), Southern America (since 1986) and in Europe (Italy since 1990) demonstrate that this vector can hardly be controlled. The Asian tiger mosquito (Aedes albopictus) exemplifies outstandingly the benefit of spreading disease vectors in expanding their area of distribution as a consequence of the complex interplay of climate change and globalisation. Nevertheless, vector establishment is not necessarily equivalent with disease outbreak. Therefore, introductions of pathogens for example by infected returning travellers have to be considered. In order to estimate the potential risk of establishment, climatic requirements of the Asian Tiger mosquito are detected, a bioclimatic envelope is modelled and connected to future climatic conditions in Europe using regional climate change simulations. Hence, the major climatic constraints of selected pathogens (e.g. Chikungunya, Dengue) which are transmitted by Ae. albopictus are estimated and transferred to projected climatic conditions. These results are combined with possible dispersal mechanisms of vector and pathogens: introduction pathways such as harbours, motorways, airports. Combining climate projections for vector and pathogen and their dispersal mechanisms may contribute to the identification of risk areas.