Climate and environmental changes are suspected as major determinants that alter the distribution and transmission patterns of certain communicable diseases, especially those transmitted by arthropods, such as ticks (e.g. tick-borne encephalitis (TBE) and Lyme disease), mosquitoes, (e.g. Chikungunya and Dengue fever), or sandflies (e.g. visceral leishmaniasis). Apart from the effect on the natural conditions and favouring a wider distribution of vectors which may carry diseases, they can also influence occupational and recreational human behaviour and lead to an increased exposure to the risk of infectious diseases e.g. through increased time spent outdoors and harvesting food in woodlands with high concentrations of ticks.