Lyme borreliosis is a bacterial tick borne infection due to Borrelia burgdorferi sensu lato. In 50% of the cases, the disease begins by a centrifuge erythema migrans localized around the tick bite. Neurological, articular and rarely cardiac, ocular or cutaneous manifestation may be observed as secondary manifestations. They sign the dissemination, the proliferation of Borrelia burgdorferisensu lato and the development of the immune response. In the absence of erythema migrans, secondary clinical manifestations may be difficult to diagnose. Direct detection of Borrelia burgdorferi sensu lato by culture is fastidious, time consuming and of a low sensitivity. Molecular methods (polymerase chain reaction) are very specific but limited by a low bacterial burden in the tissues. Serological testing interpretation is tricky but guides the diagnosis at the disseminate phase. Curative antibiotherapy is efficient, especially at the initial phase of infection. The two main elements for prophylaxis are individual protection from tick bites and a rapid and complete tick extraction. Antibioprophylaxy of tick bites is not recommended and a strict clinical surveillance must be done.