Lyme borreliosis (Lyme disease) first came to prominence about 30 years ago, following its emergence in the area of Lyme, Connecticut, USA, but its major clinical features had been described in Europe during the previous century. It is the most common vector-borne bacterial infection in temperate regions of the northern hemisphere, caused by several genospecies of Borrelia burgdorferi, a spirochaete transmitted by ticks of the Ixodes ricinus complex. In Europe, it has a widespread distribution throughout forested and woodland areas from southern Scandinavia to some parts of northern Mediterranean countries. Incidence rises from west to east. Many of the most highly endemic regions are found in central and eastern Europe. As many as 200 000 cases may occur annually. Over 35,000 confirmed or probable cases were notified in the United States in 2008. Most occur in 10 north-eastern and north-central states.
Lyme disease has been perceived as difficult to diagnose and treat, but much is now known about its clinical presentations, which largely fall into well defined categories in both adults and children. This review features recent publications on clinical diagnosis and management. The reported incidence of Lyme borreliosis has increased markedly in many countries. Many recent publications have focused on clinical and laboratory aspects of paediatric and adult neuroborreliosis, and there is now strong evidence for the efficacy of oral doxycycline for most presentations of neuroborreliosis. Serological tests have improved significantly. Several studies have confirmed that patients treated for early Lyme borreliosis have good overall long-term outcomes. Studies of patients with persistent symptoms following treatment have not shown evidence for active infection or for sustained benefit from prolonged antibiotic treatment. Greater efforts are needed to provide education for prevention and early diagnosis to avoid late complications. Further improvements in diagnostic tests would be welcomed. More research is required to assess the causes and management of post-Lyme symptoms.