Epidemiology of Lyme borreliosis based on outpatient claims data of all people with statutory health insurance, Germany, 2019

Abstract

Introduction Evidence of nationwide and regional morbidity of Lyme borreliosis (LB) in Germany is lacking. Aims We calculated the total number of incident LB cases in Germany in 2019, compared regional variations, investigated the extent of possible under-reporting in notification data and examined the association between high incidence areas and land cover composition. Methods We used outpatient claims data comprising information for people with statutory health insurance who visited a physician at least once between 2010 and 2019 in Germany (n = 71,411,504). The ICD-10 code A69.2 was used to identify incident LB patients. Spatial variations of LB were assessed by means of Global and Local Moran’s Index at district level. Notification data were obtained for nine federal states with mandatory notification from the Robert Koch Institute (RKI). Results Of all insured, 128,177 were diagnosed with LB in 2019, corresponding to an incidence of 179 per 100,000 insured. The incidence varied across districts by a factor of 16 (range: 40–646 per 100,000). We identified four spatial clusters with high incidences. These clusters were associated with a significantly larger proportion of forests and agricultural areas than low incidence clusters. In 2019, 12,264 LB cases were reported to the RKI from nine federal states, while 69,623 patients with LB were found in claims data for those states. This difference varied considerably across districts. Conclusions These findings serve as a solid basis for regionally tailored population-based intervention programmes and can support modelling studies assessing the development of LB epidemiology under various climate change scenarios.

Incidence of Lyme Borreliosis in Germany: Exploring Observed Trends Over Time Using Public Surveillance Data, 2016–2020

“…LB incidence was particularly high in the regions (NUTS2) of West-Mecklenburg and north Brandenburg (Prignitz), Dresden in Saxony, forested areas in Rheinland-Palatinate and Oberbayern, and forested areas in the Niederbayern region of Bavaria. Our data corroborate previous analyses describing German regions with high incidence (Enkelmann et al 2018 , Akmatov et al 2021 , Böhmer et al 2021 ), and indicate conducive climatic and environmental conditions in these regions for competent tick-to-host transmission and subsequent transmission to humans (Finch et al 2014 , Seukep et al 2015 , Sharareh et al 2019 ).…”

“…Out of the nine federal states, Berlin, Brandenburg, Mecklenburg-Vorpommern, Sachsen, and Sachsen-Anhalt have extended notification systems for physicians to also include laboratories, which explains higher reported laboratory-confirmed cases in some federal states (Robert Koch Institute 2017 , Enkelmann et al 2018 ). The overall incidence remained the same with no clear increase or decrease during the study period, consistent with previous analyses (Enkelmann et al 2018 , Akmatov et al 2021 ).…”

“…This results in an ∼10-fold higher LB incidence compared with the incidence obtained in our study. In addition, three health claim studies (using ICD-10 coding) estimated incidences comparable with GBE-BUND data (Muller et al 2012 , Lohr et al 2015 , Akmatov et al 2021 ). Analyses of LB incidence from administrative databases have limitations, including potential for lack of specificity for LB.…”

“…Nonetheless, additional factors such as proportion of ticks infected with B. burgdorferi and other climatic factors could play crucial roles and require further investigation (Brugger et al 2016 , Ehrmann et al 2018 ). A recent health claims analysis from Akmatov et al ( 2021 ) confirms this hypothesis, as it identified substantial burden in nonreporting states.…”

“…Seroprevalence studies have shown that Borrelia burgdorferi infections are endemic in all parts of Germany (Rath et al 1996 , Dehnert et al 2012 , Wilking et al 2015 , Woudenberg et al 2020 ). Several other observational studies, including surveillance data analyses, have documented the incidence in most regions of Germany (Huppertz et al 1999 , Muller et al 2012 , Lohr et al 2015 , Akmatov et al 2021 ).…”