Spatial distribution of typhoid and paratyphoid fever in mainland China,2011:a GIS analysis

Objective To investigate spatial distribution of typhoid and paratyphoid fever incidents in China based on geographic information system(GIS)and surveillance data,and to provide evidences for prevention and early warming of the epidemic.Methods Reported typhoid and paratyphoid fever cases in 2011 were extracted from Public Health Database issued by China Center for Disease Control and Prevention and analyzed with GIS based approach,spatial autocorrelation analysis,and trend surface analysis.Global Moran's I and Getis-Ord Gi^* were used in the analyses.Results Totally 101569 typhoid cases and 47965 paratyphoid cases were reported in China in 2011;Yunnan,Guangdong,Guangxi,and Hainan province were statistically identified with significant high values(hot spots)of spatial clusters of typhoid and paratyphoid fever.Trend surface analysis showed a downward trend from west to east and an upward trend from north to south in the incidences of typhoid and paratyphoid fever in China.Of the typhoid and paratyphoid fever cases reported,55.40% and 55.13% were male,and 75.51% and 78.01% were at the ages of 0-45 years.Among the typhoid and paratyphoid fever cases,around one-third(38.19% and 30.75%)were farmers and more than one-fifth(23.58% and 21.75%)were students.Conclusion Spatial and population distribution of typhoid and paratyphoid fever should be concerned when making strategies for prevention and control of the epidemic.