Spatio-temporal distribution characteristics of alveolar echinococcosis in Xiji County, Ningxia Hui Autonomous Region, 2005-2024

CHINESE JOURNAL OF PARASITOLOGY AND PARASITIC DISEASES ›› 2025, Vol. 43 ›› Issue (6): 757-765.doi: 10.12140/j.issn.1000-7423.2025.06.003

• ORIGINAL ARTICLES • Previous Articles     Next Articles

Spatio-temporal distribution characteristics of alveolar echinococcosis in Xiji County, Ningxia Hui Autonomous Region, 2005-2024

XIAN Yuying1(), TIAN Huifang1, FU Weicheng1, YAN Fang2, XUE Chuizhao3, WANG Ying3, WU Xianglin2,*()(), WANG Xu3,*()()   

  1. 1 Xiji County Center for Disease Control and Prevention, Guyuan 756200, Ningxia, China
    2 Ningxia Hui Autonomous Region Center for Disease Control and Prevention, Yinchuan 750011, Ningxia, China
    3 National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Chinese Center for Tropical Diseases Research; National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases; Key Laboratory on Parasite and Vector Biology, Ministry of Health; WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Ministry of Science and Technology, Shanghai 200025, China
  • Received:2025-08-20 Revised:2025-10-30 Online:2025-12-30 Published:2025-12-29
  • Contact: *E-mail: wangxu@nipd.chinacdc.cn;545126419@qq.com
  • Supported by:
    National Natural Science Foundation of China(82404325)

Abstract:

Objective To comprehensively analyze the spatiotemporal distribution of human alveolar echinococcosis (AE) in Xiji County and to identify underlying environmental factors, thereby providing a scientific basis for targeted prevention and control strategies. Methdos Surveillance data on human AE case in Xiji County (2005-2024) were collected. The annual number of cases by township was visualized using heatmaps. Joinpoint regression models were utilized to analyze temporal trends in incidence rates, calculating the average annual percentage change (AAPC) and annual percentage change (APC). R language packages were used to compute and plot the trends in annual prevalence rates. ArcGIS was employed for spatial visualization, global and local Moran’s I index analyses to assess spatial autocorrelation, and SaTScan was performed for space-time scan analysis to identify spatiotemporal clusters. A multivariable logistic regression model were constructed to analyze the association between plant formation area and AE occurrence at the village level. Results A total of 325 human AE cases were identified in Xiji County over the 20-year period, with the peak incidence rate occurring in 2007 (33.87/100 000). The incidence rate has shown a significant downward trend (AAPC = -13.27%, P < 0.01) in the past 15 years, and the prevalence rate of AE also showed a consistent decline (Z = -21.98, P < 0.01) from 2015 to 2024. The average annual incidence (countywide: 4.03/100 000) showed an uneven geographical distribution: higher in northern townships (Xinying: 31.64/100 000; Baiya: 30.63/100 000) and lower in the south. Spatiotemporal scan analysis identified a significant primary cluster encompassing Xinying, Baiya, and Huoshizhai townships for the period 2007-2009 (RR = 30.90, LLR = 288.76, P < 0.01). Cases were reported in 34.09% of all villages/communities, with exceptionally high endemic village proportions within Xinying (95.45%) and Baiya (92.86%) townships. Logistic regression revealed that increased area coverage of Stipa bungeana steppe, cropland, and Artemisia giraldii-grass steppe significantly elevated the AE risk at the village level (OR = 1.32, 1.12, 1.44; all P < 0.05). Conclusion The AE epidemic in Xiji County is characterized by a historically high burden in the north, significant spatiotemporal clustering, and a marked overall decline over the past 15 years. Key vegetation biomes are significant risk factors, elevating AE risk by shaping suitable habitats for rodent intermediate hosts and influencing human exposure activities. Although comprehensive control strategies have significantly reduced the AE incidence and prevalence rates in Xiji County, persistent transmission risks remain.

Key words: Echinococcosis, Echinococcus multilocatus, Epidemiology, Ningxia, Xiji

CLC Number: