Epidemiological situation of Lyme borreliosis in germany: surveillance data from six Eastern German States, 2002 to 2006.

Lyme borreliosis is the most frequent vector-borne disease in Germany; however, in only six states in the eastern part of Germany (Berlin, Brandenburg, Mecklenburg Western Pomerania, Saxony, Saxony-Anhalt and Thuringia) is early Lyme disease (erythema migrans and early neuroborreliosis) a notifiable disease. Between 2002 and 2006, the incidence increased constantly; in 2002, the incidence per 100,000 inhabitants was 17.8 and rose by 110% to 37.3 in 2006. The incidence among the states varies greatly with Brandenburg accounting for the highest incidence (77.6 per 100,000 inhabitants) and Berlin for the lowest incidence (5.7 per 100,00 inhabitants). The age distribution is bimodal with incidence peaks in childhood between the ages 5 to 9 and in adulthood in the age group 65 to 69 years. In general, females are more frequently affected than males (55% versus 45%). Erythema migrans and early neuroborreliosis affected 20,787 patients (90%) and 799 patients (3%), respectively. Around 70% of all cases occurred between June and September. Further studies are needed to answer the question to which extent the annual increase can be related to a changing epidemiological situation or to other factors such as growing awareness, better diagnostic tools and changing recreational habits.