Mapping the risk distribution of Borrelia burgdorferi sensu lato in China from 1986 to 2020: a geospatial modelling analysis

Emerg Microbes Infect. 2022 Dec;11(1):1215-1226. doi: 10.1080/22221751.2022.2065930.

Abstract

Lyme borreliosis, recognized as one of the most important tick-borne diseases worldwide, has been increasing in incidence and spatial extent. Currently, there are few geographic studies about the distribution of Lyme borreliosis risk across China. Here we established a nationwide database that involved Borrelia burgdorferi sensu lato (B. burgdorferi) detected in humans, vectors, and animals in China. The eco-environmental factors that shaped the spatial pattern of B. burgdorferi were identified by using a two-stage boosted regression tree model and the model-predicted risks were mapped. During 1986-2020, a total of 2,584 human confirmed cases were reported in 25 provinces. Borrelia burgdorferi was detected from 35 tick species with the highest positive rates in Ixodes granulatus, Hyalomma asiaticum, Ixodes persulcatus, and Haemaphysalis concinna ranging 20.1%-24.0%. Thirteen factors including woodland, NDVI, rainfed cropland, and livestock density were determined as important drivers for the probability of B. burgdorferi occurrence based on the stage 1 model. The stage 2 model identified ten factors including temperature seasonality, NDVI, and grasslands that were the main determinants used to distinguish areas at high or low-medium risk of B. burgdorferi, interpreted as potential occurrence areas within the area projected by the stage 1 model. The projected high-risk areas were not only concentrated in high latitude areas, but also were distributed in middle and low latitude areas. These high-resolution evidence-based risk maps of B. burgdorferi was first created in China and can help as a guide to future surveillance and control and help inform disease burden and infection risk estimates.

Keywords: BRT; Borrelia burgdorferi sensu lato; Lyme borreliosis; modelling; spatial risk.

MeSH terms

  • Animals
  • Borrelia burgdorferi Group*
  • Borrelia burgdorferi* / genetics
  • China / epidemiology
  • Ixodes*
  • Ixodidae*
  • Lyme Disease* / epidemiology

Grants and funding

This work was supported by the Key Research and Development Program of China [grant number 2019YFC1200604], the National Natural Science Foundation of China [grant number 81825019], and the China Mega-Project on Infectious Disease Prevention [grant numbers 2018ZX10201001, 2018ZX10713001, 2018ZX10713002].