Seite - 74 - in Biodiversity and Health in the Face of Climate Change

74 Japanese encephalitis, dengue, chikungunya, lymphatic filariasis and visceral leish- maniasis towards a cooler mountainous region has been reported from Nepal (Dhimal et  al. 2014a, 2015; Ostyn et  al. 2015). Altitude is often used as a proxy for temperature changes, so one may speculate that this trend might also be true for more northern/temperate regions. In Europe, four exotic Aedes types of mosquitoes are currently found (partly reviewed in Medlock et  al. 2012): the Asian tiger mosquito (Ae. albopictus; Adhami and Reiter 1998), the yellow-fever mosquito (Ae. aegypti; Goncalves et  al. 2008), the Asian bush mosquito (Ae. japonicus japonicus; Schaffner et  al. 2009) and Ae. koreicus (Versteirt et  al. 2012). Particularly, the Asian tiger mosquito Ae. albopictus with widespread European distribution is a competent vector for several VBDs and therefore poses human public health risks. It is suspected that the Asian tiger mos- quito was the main vector for dengue viruses in France in 2015 (Succo et  al. 2016) and for chikungunya virus in Italy in 2007 and 2017 (Rezza 2018) (autochthonous cases in Europe 2007–2012 reviewed in Tomasello and Schlagenhauf 2013). These cases show how human transport activities and temperature change facilitate the establishment of vector species and highlight the importance of actively preventing such establishments (Eritja et  al. 2017; Ducheyne et  al. 2018, Reuss et  al. 2018, Dhimal et  al. 2018). Despite temperature, climate change will lead to hydrological changes. For Ae. albopictus in Europe, it is projected that Mediterranean locations will become more unsuitable habitats due to climatic variables and changed water regimes, while suit- ability is increased in middle and northern Europe up to 55°N (Fischer et  al. 2014). Climate and photoperiod also alter the host-seeking and feeding activity in ticks as well as the seasonal occurrence of vector stages (Altizer et  al. 2013; Kurtenbach et  al. 2006). 4.2.3 Distributional Changes of  Ticks in  Europe There are objective grounds that climate change influences the distribution and sea- sonal activity of disease-transmitting ticks (Ogden et  al. 2014). The tick Ixodes rici- nus is medically highly relevant as a vector for spirochaete bacteria Borrelia burgdorferi, with Lyme disease extending its distribution northwards in Europe, in a warmer climate (Lindgren et  al. 2000). The taiga tick (Ixodes persulcatus), trans- mitting the ‘early summer’ meningo-enzephalitis virus, is currently spread from Russia west-northwards to Scandinavia (Jaenson et  al. 2016). Ticks of the genera Dermacentor with a previously Mediterranean distribution, for instance the Coxiella burnetti-transmitting sheep tick Dermacentor marginatus (Q fever,) are now estab- lished in cold-temperate Germany (Földvári et  al. 2016). The Mediterranean tick Hyalomma marginatum is the main vector for the emerging pathogen Crimean- Congo Hemorrhagic Fever in Europe. International livestock trading guarantees the tick’s mobility, as ticks live on domestic animals, while the degradation of agricul- tural land favours the mass development of Hyalomma marginatum (Estrada-Pena R. Müller et al.