Exploratory study of factors associated with human brucellosis in mainland China based on time-series-cross-section data from 2005 to 2016

Abstract

ObjectiveMany studies focused on reasons behind the increasing incidence and the spread of human brucellosis in mainland China, yet most of them lacked comprehensive consideration with quantitative evidence. Hence, this study aimed to further investigate the epidemic mechanism and associated factors of human brucellosis in China so as to provide suggestions on more effective countermeasures.MethodsData of human brucellosis incidence and some associated factors in economy, animal husbandry, transportation and health were collected at provincial level from 2005-2016. Time series plot and cluster analysis were first used to visualize incidence levels and categorize provinces based on their incidence level and epidemic trend of human brucellosis. Furthermore, according to the characteristics of data, the dynamic panel data model in combination with supervised principal component analysis was proposed to explore the effects of associated factors on human brucellosis.Results① The incidence rate of human brucellosis has increased threefold (from 1.41 in 2005 to 4.22 in 2016) in mainland China. Incidence rates in the north have always been higher than those in the south, but the latter also experienced an upward trend especially in the recent five years. ② The 31 provinces of mainland China were categorized into three clusters, and each cluster had its own characteristics of incidence level and epidemic trend. ③ Public health expenditure and rural medical expenditure proportion were potential protective factors of human brucellosis, with attribute risks of −0.74 and −1.04 respectively. Other factors (such as amount of sheep, total length of highways, etc.) exhibited relatively trivial effects.ConclusionsThe epidemic status of human brucellosis has changed in both spatial and temporal dimensions in recent years. Apart from those traditional control measures, more attention should be paid to the improvement of medical healthcare especially in rural areas in order to strengthen the control effect.