Substantial Rise in the Prevalence of Lyme Borreliosis Spirochetes in a Region of Western Germany over a 10-Year Period

Abstract

More than a decade after a study on the transmission cycle of Borrelia burgdorferi sensu lato in the Siebengebirge, a nature reserve near Bonn, Germany, questing nymphal and adult Ixodes ricinus ticks were collected again in three selected areas of the same low mountain range and examined for infection with B. burgdorferi sensu lato. Between May and October 2001, a total of 1,754 ticks were collected by blanket dragging; 374 ticks were analyzed for B. burgdorferi sensu lato by both an immunofluorescence assay (IFA) and at least two different PCR tests, whereas 171 ticks were analyzed by PCR only. By combining all assays, an average of 14% of the ticks tested positive for B. burgdorferi sensu lato, 5.5, 15.8, and 21.8% in the three collection areas. Of the nymphs and adults examined, 12.9 and 21.1%, respectively, were found to be spirochete infected. A lower total infection prevalence was obtained by IFA (14.4%) than by a nested PCR approach (16.5%), but both were higher than that obtained by a simple PCR approach (11.9%). Compared with data collected over a decade ago, the mean infection prevalence of B. burgdorferi sensu lato in the ticks was significantly higher for all three biotopes, whereas a similar pattern of habitat-specific infection prevalence was observed. Genotyping of B. burgdorferi sensu lato revealed high relative prevalences of B. valaisiana (identified in 43.1% of infected ticks) and B. garinii (32.3%), whereas B. afzelii (12.3%) and B. burgdorferi sensu stricto (1.5%) were relatively rare. We conclude that B. burgdorferi sensu lato infection has increased in this region over the last 15 years due to presently unknown changes in ecological conditions, perhaps related to climate change or wildlife management.

Prevalence of Borrelia burgdorferi Sensu Lato and Anaplasmataceae Members in Ixodes ricinus Ticks in Alsace, a Focus of Lyme Borreliosis Endemicity in France

“…Nymph activity drastically declined from September and disappeared in November. The adult activity showed a drop as early as June in 2004, and the density remained more or less stable until November, when adults also disappeared (Table 1) (22,35,36).…”

Variations inIxodes ricinusDensity andBorreliaInfections Associated with Cattle Introduced into a Woodland in The Netherlands

“…In recent years, a rapid rise in the number of Lyme disease cases has been reported in Germany and The Netherlands (8,13), and it has been postulated that this might be due to an expansion of nature reserves, a steady rise in roe deer populations, and increased outdoor recreation. For the management of woodlands, wardens of nature reserves increasingly turn to grazing by free-ranging bovids, as this can keep the woodlots "open" and helps to keep the vegetation diverse (22).…”

Disulfide-Mediated Oligomer Formation in Borrelia burgdorferi Outer Surface Protein C, a Critical Virulence Factor and Potential Lyme Disease Vaccine Candidate

“…These data indicate that the immune response to OspC is not significantly altered by formation of OspC oligomers, a finding that has significant implications in Lyme disease vaccine design. (2,3,9,21,25,31). B. burgdorferi is maintained in an enzootic cycle involving Ixodes ticks and reservoir mammals and birds (4, 5, 18).…”

“…Lyme borreliosis is an emerging infectious disease in North America and Europe caused by the spirochetes Borrelia burgdorferi, Borrelia garinii, and Borrelia afzelii (2,3,9,21,25,31). B. burgdorferi is maintained in an enzootic cycle involving Ixodes ticks and reservoir mammals and birds (4,5,18).…”