Seroprevalence of Lyme Borreliosis in Europe: Results from a Systematic Literature Review (2005-2020)

Abstract

Background: Lyme borreliosis (LB), a tick bite-transmitted infection caused by Borrelia burgdorferi sensu lato (Bbsl) complex spirochetes, is the most common tickborne disease in Europe. Studies in European countries have reported LB seroprevalence (prevalence of antibodies to Bbsl infection) and diagnostic strategies used for testing. We conducted a systematic literature review to summarize contemporary LB seroprevalence in Europe. Methods: PubMed, Embase, and CABI Direct (Global Health) databases were searched from 2005 to 2020 to identify studies reporting LB seroprevalence in European countries. Reported single-tier and two-tier test results were summarized; algorithms (standard or modified) were used to interpret final test results from studies that used two-tier testing. Results: The search yielded 61 articles from 22 European countries. Studies used a range of diagnostic testing methods and strategies (48% single-tier, 46% standard two-tier, and 6% modified two-tier). In 39 population-based studies, of which 14 were nationally representative, seroprevalence estimates ranged from 2.7% (Norway) to 20% (Finland). There was substantial heterogeneity among studies in terms of design, cohort types, periods sampled, sample sizes, and diagnostics, which limited cross-study comparisons. Nevertheless, among studies that reported seroprevalence in persons with greater exposure to ticks, LB seroprevalence was higher among these groups than in the general population (40.6% vs. 3.9%). Furthermore, among studies that used two-tier testing, general population LB seroprevalence was higher in Western Europe (13.6%) and Eastern Europe (11.1%) than in Northern Europe (4.2%) and Southern Europe (3.9%). Conclusion: Despite variations in LB seroprevalence between and within European subregions and countries, high seroprevalence was observed in certain geographic regions and particular risk groups, suggesting significant disease burden and supporting the need for improved, targeted public health interventions such as vaccination. Harmonized approaches to serologic testing and more nationally representative seroprevalence studies are needed to better understand the prevalence of Bbsl infection in Europe.

Keywords: Europe; Lyme borreliosis; diagnostics; epidemiology; seropositivity; seroprevalence.

FIG. 1.

Algorithm for the serologic testing of LB (Centers for Disease Control and Prevention , Marques , Branda and Steere 2021). Overall test results should be used from two-tier testing, with the original denominator. ^aEIA or IFA WCS. C6, C6 protein of the variable major protein-like sequence lipoprotein; EIA, enzyme immunoassay; IFA, immunofluorescence assay; IgG, immunoglobulin G; IgM, immunoglobulin M; LB, Lyme borreliosis; WCS, whole-cell sonicate.

FIG. 2.

PRISMA flow diagram. PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses.

FIG. 3.

Heat map of number of publications by country from literature published between 2005 and 2020. N = 61.