Spatiotemporal patterns and environmental drivers of human echinococcoses over a twenty-year period in Ningxia Hui Autonomous Region, China

Cadavid Restrepo, Angela M.; Yang, Yu Rong; McManus, Donald P.; Gray, Darren J.; Barnes, Tamsin S.; Williams, Gail M.; Soares Magalhães, Ricardo J.; Hamm, Nicholas A.S; Clements, Archie C.A.

Abstract

Background

Human cystic (CE) and alveolar (AE) echinococcoses are zoonotic parasitic diseases that can be influenced by environmental variability and change through effects on the parasites, animal intermediate and definitive hosts, and human populations. We aimed to assess and quantify the spatiotemporal patterns of human echinococcoses in Ningxia Hui Autonomous Region (NHAR), China between January 1994 and December 2013, and examine associations between these infections and indicators of environmental variability and change, including large-scale landscape regeneration undertaken by the Chinese authorities.

Methods

Data on the number of human echinococcosis cases were obtained from a hospital-based retrospective survey conducted in NHAR for the period 1 January 1994 through 31 December 2013. High-resolution imagery from Landsat 4/5-TM and 8-OLI was used to create single date land cover maps. Meteorological data were also collected for the period January 1980 to December 2013 to derive time series of bioclimatic variables. A Bayesian spatio-temporal conditional autoregressive model was used to quantify the relationship between annual cases of CE and AE and environmental variables.

Results

Annual CE incidence demonstrated a negative temporal trend and was positively associated with winter mean temperature at a 10-year lag. There was also a significant, nonlinear effect of annual mean temperature at 13-year lag. The findings also revealed a negative association between AE incidence with temporal moving averages of bareland/artificial surface coverage and annual mean temperature calculated for the period 11–15 years before diagnosis and winter mean temperature for the period 0–4 years. Unlike CE risk, the selected environmental covariates accounted for some of the spatial variation in the risk of AE.

Conclusions

The present study contributes towards efforts to understand the role of environmental factors in determining the spatial heterogeneity of human echinococcoses. The identification of areas with high incidence of CE and AE may assist in the development and refinement of interventions for these diseases, and enhanced environmental change risk assessment.

Citation

Cadavid Restrepo, A. M., Yang, Y. R., McManus, D. P., Gray, D. J., Barnes, T. S., Williams, G. M., Soares Magalhães, R. J., Hamm, N. A., & Clements, A. C. (2018). Spatiotemporal patterns and environmental drivers of human echinococcoses over a twenty-year period in Ningxia Hui Autonomous Region, China. Parasites and Vectors, 11, Article 108. https://doi.org/10.1186/s13071-018-2693-z

• Journal Article Type: Article
• Acceptance Date: Feb 2, 2018
• Publication Date: Feb 22, 2018
• Deposit Date: Jul 19, 2018
• Publicly Available Date: Jul 19, 2018
• Journal: Parasites and Vectors
• Electronic ISSN: 1756-3305
• Publisher: Springer Verlag
• Peer Reviewed: Peer Reviewed
• Volume: 11
• Article Number: 108
• DOI: https://doi.org/10.1186/s13071-018-2693-z
• Keywords: Echinococcosis; Cystic echinococcosis; Alveolar echinococcosis; Spatial analysis; Environmental change; ; Remote sensing
• Public URL: https://nottingham-repository.worktribe.com/output/912849
• Publisher URL: http://dx.doi.org/10.1186/s13071-018-2693-z
• Contract Date: Jul 19, 2018