Surveillance of Lyme borreliosis in Germany, 2002 and 2003

Lyme borreliosis is a potentially serious infection common in Germany, but little data about its incidence, distribution, and clinical manifestations are available. Lyme borreliosis is not a notifiable disease in Germany, but six of Germany's 16 states - Berlin, Brandenburg, Mecklenburg-Vorpommern, Sachsen, Sachsen-Anhalt and Thüringen, have enhanced notification systems, which do include Lyme borreliosis. The efforts made in these states to monitor confirmed cases through notification are therefore an important contribution to understanding the epidemiology of Lyme borreliosis in Germany. This report summarises the analysis of Lyme borreliosis cases submitted to the Robert Koch-Institut during 2002-2003. The average incidence of Lyme borreliosis of the six East German states was 17.8 cases per 100,000 population in 2002 and increased by 31% to 23.3 cases in 2003, respectively. Patient ages were bimodally distributed, with incidence peaks among children aged 5- 9 and elderly patients, aged 60- 64 in 2002, and 65- 69 in 2003. For both years, 55% of patients were female. Around 86% of notified cases occurred from May to October. Erythema migrans affected 2697 patients (89.3%) in 2002 and 3442 (86.7%) in 2003. For a vector-borne disease, like Lyme borreliosis, the risk of infection depends on the degree and duration of contact between humans and ticks harbouring Borrelia burgdorferi. As infectious ticks probably occur throughout Germany, it is likely that the situation in the remaining 10 German states is similar to that of the states in this study.