[Tick-borne human pathogenic microorganisms found in Europe and those considered nonpathogenic. Part II: Bacteria, parasites and mixed infections].

The importance of tick-borne diseases has significantly increased objectively and subjectively during the last few years. This fact was demonstrated by the description of tick-borne viruses, in particular with respect to tickborne encephalitis published in part I. Here in part II, tick-borne bacteria and parasites will be discussed as well the significance of these agents, their vectors, clinical course, diagnostics, prophylaxis, and therapy. Naturally, Lyme borreliosis, one of the most important tick-borne bacterial illnesses of humans, is the center of our interest. In addition to basic understanding, critical practice-relevant advice regarding all agents is presented. Similarly all tick-borne bacterial diseases such as relapsing fever, tularemia, ehrlichiosis, and rickettsiosis including Q fever will be discussed. Tick-borne zoonotic babesiae are parasites whose veterinary importance has been known for the last 100 years but whose relevance for human medicine only became evident in 1957. The fact that multiple and mixed infections caused by ticks are possible has been known for years. Taking into account such a high prevalence of the infectious agents in ticks, such multiple infections were to be expected. During the last few years it has become evident that double and multiple infections of humans caused by tick bites occur far more frequently than has been known so far. As a result, in cases of unclear anamnesis,new diagnostic and therapeutic approaches should be taken. In general one can say that considerable additional scientific research is necessary to effectively reduce the incidence of tick-borne diseases.