Spatial characteristics of incidence of scarlet fever in Kaifeng City,Henan Province,2012-2022
Objective To analyze the epidemiological and spatial distribution characteristics of scarlet fever cases in Kaifeng City,Henan Province from 2012 to 2022 so as to provide a basis for scarlet fever prevention and control in Kaifeng City.Methods We descriptively analyzed the time,population and region of the reported cases of scarlet fever in Kaifeng City of Henan Province.ArcGIS 10.6 software was used to draw the statistical map of incidence of scarlet fever and perform the spatial autocorrelation analysis.Results A total of 678 cases of scarlet fever were reported in Kaifeng City,Henan Province during 2012-2022,with an average annual incidence rate of 1.56/100,000.The incidence rates showed a trend of first increasing and then decreasing(x2=859.33,P<0.001).There was no statistically significant difference in the incidence rate between males and females(x2=2.01,P>0.05).The patients'ages were mainly less than 25 years old(n=667,98.4%),and mainly concentrated at the group aged 10-15 years(n=374,55.2%).The incidence rate was found to be the highest in the group aged 10-15 years,and most of them were students(52.5%).The incidence rates in 0-13 years old showed an upward trend(x2trend=6,503.22,P<0.001),but a downward trend with the increase of age(x2trend=6,965.24,P<0.001).Time trends in the incidence of scarlet fever showed a bimodal distribution,the fourth quarter of each year was the main peak incidence,with the incidence rate being 5.55/100,000(32.4%),and the second quarter was secondary peak,with the incidence rate of 4.44/100,000(26.0%).The average annual incidence rate in the northwestern central area of Kaifeng City(4.56/100,000)was higher than that in the southeastern suburban area(0.39/100,000),with a statistically significant difference(x2=864.67,P<0.001).Global spatial autocorrelation analysis revealed that there was a positive spatial correlation in the spatial distribution of incidence rates of scarlet fever in districts and counties,with spatial aggregation(Moran's I=0.129,P=0.02).Local spatial autocorrelation analysis displayed that there were spatial height-height clustering phenomena in five districts and counties.A total of 33 scarlet fever clusters and 9 outbreaks were reported in Kaifeng City from 2012 to 2022,mainly occurring in kindergartens and primary schools(83.33%),involving 247 cases of scarlet fever(36.43%),and mainly occurring in the fourth quarter(69.05%)and the second quarter(23.81%).Conclusion The regional distribution of incidence rates of scarlet fever in Kaifeng City of Henan Province in 2012-2022 showed spatial clustering characteristics,mainly involving the northwestern central urban area,and the incidence rates of scarlet fever showed a downward trend from north to south and from west to east.The results suggest that targeted preventive and control measures against scarlet fever should be conducted based on the key population in key districts.
scarlet feverepidemiological characteristicspatial distribution