Parasites threaten still today the health of humans and their animals, although considerable progress had been achieved within the last century. However, phenomena such as globalization with the daily transportations of millions of containers and humans from one end of the world to the other make it easy. For agents of disease and their vectors to suddenly occur at places which were thought to be safe. Thus, it is not astonishing that worldwide so-called emerging diseases occur at a formerly unbelievable speed. The ongoing climate change additionally offers better conditions for many agents of disease and their vectors to enter and to settle in formerly untouched regions. Therefore, it is needed to observe intensively the development and progress of such aggressive organisms.