Infection with Borrelia burgdorferi s.l. causes disease (Lyme borreliosis)in horses in Germany

High seroprevalence (47.9 %) of antibody (AB) titers against B. burgdorferi s.l. were demonstrated in 1492 horses clinically suspicious unsuspicious f or Lyme borreliosis (LB) in Germany. For the first time in Germany and poss ibly in Europe cases of sick horses are described in which clinical symptom s of LB and high AB titers occurred, and intra vitam Borrelia were isolated and were typed as B. burgdorferi s.l. after culturing. The main clinical s ymptoms in four horses were cachexia, polyarthritis, keratitis, endocarditi s, acrodermatitis, sarcoid, hyperesthesia and somnolence. Intra vitam Borre lia were repeatedly cultured from biopsy samples of the skin and the conjun ctiva and synovia. Post mortem Borrelia were isolated form the skin, synovi al membranes of several joints, the eyes (conjunctiva, cornea, sklera and r etina),several lymph nodes, the truncus aortae, lungs, liver, spleen, kidne y and brain. It is assumed in accordance with KOCH's postulates that Borrel ia burgdorferi sensu late is the causative agent of Lyme borreliosis in hor ses in Germany and other parts of Europe. Thus the diagnosis chronic Lyme b orreliosis was made.