[Lyme disease: how widespread is the problem?].

Lyme disease is the cause of a lot of anxiety and discussion. Patients are demanding more preventive actions to avoid tick bites, and earlier and better diagnosis of Lyme disease. However, only a minority of people bitten by a tick go on to develop Lyme disease. Although physician delay may lead to a late diagnosis of disseminated Lyme disease, these patients are still treatable and even in bad cases, symptoms will subside within a few years. While we know that serious complications of late disseminated Lyme, e.g. neuroborreliosis, are very rare, there is still uncertainty about how often Lyme disease occurs, and how often the diagnosis is delayed. The high prevalence of seropositive people in the population suggests that many people clear the infection without any symptoms and without any treatment. Some decades ago mononucleosis infectiosa also had a bad reputation but this largely disappeared when it became clear that recovery is the rule. Lyme disease may also shed its reputation once the facts are known.