[Prevalence and relevance of avian Toxoplasma gondii infections in Europe].

Toxoplasma (T.) gondii is a parasitic protozoon whose life cycle includes a definite and an intermediate host. Besides a wide range of mammals also birds are suitable intermediate hosts. There are a high number of case reports, prevalence data and experimental studies regarding avian toxoplasmosis. In many domestic, wild and zoo bird species which are relevant in Europe the susceptibility for T. gondii infection could be demonstrated though susceptibility for clinical disease often seems to be low, especially in gallinaceous birds. Comprehensive Europe-wide studies concerning the occurrence of avian toxoplasmosis have not been conducted so far. The general infestation ratio of birds on European free-range poultry farms seems to be relatively high. The European wild bird population represents a significant reservoir for the pathogen. When evaluating the seroprevalence it has to be considered that sensitivity and specificity of the detection methods for T. gondii specific antigens which are used frequently in mammals often are not satisfying in birds.