As intestinal infectious diseases are one major public health issue in China, there remains an urgent need to dynamically track the incidence trend and epidemiological characteristics of these diseases on the whole or by category.

To analyze the epidemiological characteristics, spatial distribution and clustering features of types A and B intestinal infectious diseases in China from 2008 to 2018, providing a theoretical basis for optimizing the prevention and control strategies of these two types of diseases.

Data on the incidence of types A and B intestinal infectious diseases〔including typhoid and paratyphoid, viral hepatitis (hepatitis A, hepatitis E and undifferentiated type of hepatitis) and dysentery〕in all regions of China (n=31, except for Hong Kong, Macao and Taiwan) from January 2008 to December 2018 were extracted in March 2022, using the Data-center China Public Health Science as the data source. The chi-square test for trend was used to examine the temporal trend of incidence of these two types of diseases. Descriptive epidemiology, spatial autocorrelation, and spatial and temporal clustering analysis were used to analyze the spatio-temporal epidemiological characteristics of the diseases, and to determine the key seasons and regions for epidemic prevention and control.

A cumulative total of 3 220 480 cases of types A and B intestinal infectious diseases were reported in China from 2008 to 2018, with an average annual incidence rate of 7.25/100 000, showing a decline in overall incidence rate (P<0.05) . The incidence rate of typhoid and paratyphoid, viral hepatitis and dysentery demonstrated a downward trend during the period (P<0.05) . The incidence rate of typhoid and paratyphoid decreased from 1.18 per 100 000 population in 2008 to 0.78 per 100 000 population in 2018. The incidence rate of viral hepatitis decreased from 9.81 per 100 000 population in 2008 to 4.34 per 100 000 population in 2018. The incidence rate of dysentery decreased from 23.65 per 100 000 population in 2008 to 6.56 per 100 000 population in 2018. Typhoid, paratyphoid and dysentery occurred more frequently in summer and autumn (from May to October) , while the incidence of viral hepatitis had no obvious changes across seasons. The spatial distribution map of types A and B intestinal infectious diseases in China indicated that, typhoid and paratyphoid had a high incidence rate in Yunnan, Guizhou and Guangxi in western China, viral hepatitis showed a high incidence rate in western China, and dysentery had a high incidence rate in Beijing and Tianjin. The spatial autocorrelation analysis showed that the incidence rate of typhoid and paratyphoid (except that in 2014) , viral hepatitis (except that in 2016) and dysentery in China over the years from 2008 to 2018 was spatially clustered (global Moran's I ranged from 0.09 to 0.24, P<0.05) . The spatial clustering of typhoid and paratyphoid and viral hepatitis was decreased first and then increased, and that of viral hepatitis declined first and then rose, but was weakened in general. The spatial clustering of dysentery was strong. The spatio-temporal scan statistics detected that Yunnan was the region with the highest incidence rate (the primary geographic cluster) of typhoid and paratyphoid during 2009 to 2013, nine regions with Tibet as the center had the highest incidence rate of viral hepatitis from 2008 to 2011, and Beijing and Tianjin were the regions with the highest incidence rate of dysentery from 2008 to 2012.

Having obvious spatial and temporal clustering characteristics, the incidence of types A and B intestinal infectious diseases in China decreased significantly during the period due to effective prevention and control. Our study may be used as a guide to identify key prevention and control areas and to develop prevention and control strategies according to the spatial clustering patterns of different intestinal infectious diseases.