The Impact of Socio-Environmental Drivers and Japanese Encephalitis in Shaanxi, China, a Bayesian Spatial Analysis

摘要

Background: With the progress of global climate change and more extreme weather events, areas with lower mosquito borne disease incidence also meet with resurgence of disease. This study examined the association of meteorological and socio-demographical factors with Japanese encephalitis JE (2006-2014) in Shaanxi, China. Methods: JE data at the county level in Shaanxi were supplied by Shaanxi Center for Disease Control and Prevention. Population and socioeconomic data were provided by China Population Census in 2010 and statistical yearly book. Meteorological data were acquired from China Meteorological Administration. A Bayesian conditional autoregressive model was used to examine the association of meteorological and socioeconomic factors on JE. Results: A total of 1,197 JE cases were included in this study. The north of Shaanxi had lowest JE incidence while the south had the highest in most of the study years. Urbanization rate was inversely associated with JE incidence in the whole study period. Meteorological variables were more significantly associated with JE incidence between 2012 and 2014 than earlier years. The north had higher incidence from August to October, 2013 than the middle and south, which may be associated with the excessive precipitation in the north in July, 2013 with 1-3 months lag effect. The spatial residual variations indicated that the whole study area had more stable risk (0.80-1.19 across all the counties) between 2012 and 2014 than earlier years. Conclusion: Extreme weather outweighed other variables in association with spatial pattern of JE incidence. Public health interventions need to be implemented to reduce JE incidence, especially in rural areas and after extreme weather, e.g., rainfall.