Spatial Analysis on Measles in Liaoning Province,China,2013-2015 / 中国医科大学学报

Objective To explore the spatial distribution of measles from 2013 through 2015 in Liaoning province,China and to provide references for measles control and prevention. Methods The GeoDa 1.4. 6 program was used to conduct exploratory spatial data analysis to identify the spatial distribution characteristics and pattern of measles in Liaoning province. Results The frequency analysis showed that the measles epidemic situation appeared to have significant positive skewing within 105 counties of Liaoning province in each year from 2013 through 2015. The global trend analysis indicated a balanced trend in 2013 and 2015,and that the high incidence measles areas were located in the eastern and northern provincial regions in 2014. The global Moran'sⅠwas 0.294 5,0.391 9,and 0.147 7,and general G values were 0.015 9,0.012 0,and 0.013 5,revealing a positive spatial autocorrelation and a high-high aggregation model for each year between 2013 and 2015. The local spatial autocorrelation analysis recognized 5 core areas and 25 hot-spot counties with a high incidence of the measles epidemic,mainly distributed in Shenyang,Fuxin,Tieling,Fushun,Benxi,Liaoyang,Panjin,and Huludao. Conclusion Measles cases were clustered geographically in Liaoning province from 2013 through 2015. Spatial epidemiology methods may offer insights for the epidemiologic study of measles.

Spatial clustering and changing trend of hand-foot-mouth disease during 2008-2011 in China / 中华流行病学杂志

Objective The purpose of this study was to explore the spatial clustering,specific clustering areas,as well as changing trend of clustering areas of hand-foot-mouth disease (HFMD).Methods Exploratory spatial data analysis (ESDA) was used to conduct spatial statistical analyses for the HFMD using 2008-2011 data at both provincial and county/district levels.Results The Global Moran' s I coefficients appeared to be 0.3336,0.6074,0.3372,0.4620 and 0.4367 for 2008-2011and for the combined 4 years,respectively.The corresponding P-values were 0.002,0.001,0.004,0.001 and 0.001 respectively,when using the Monte Carlo tests with all the P-values less than 0.05.Moran' s Ⅰ coefficients ranged between 0.3 and 0.7,showing the appearance of moderate or higher clustering nature.Based on the results from nationwide analyses on clustering areas at the county/district levels between 2008 and 2011 (Moran' s I=0.5198,P=0.001),it appeared a moderate clustering nature.When local autocorrelation analysis was applied at the provincial level,3 hot spot areas in Beijing,Tianjin and Shanghai cities in 2008；7 hot spot areas in Beijing,Tianjin,Hebei,Shanxi,Shanghai,Jiangsu and Shandong in 2009; four hot spot areas:Beijing,Tianjin,Guangdong and Guangxi; five hot spot areas:Fujian,Jiangxi,Hunan,Guangdong and Guangxi in 2011,were discovered.390 hot-spot counties/districts were found through local autocorrelation analyses using the three-year data of 2008 to 2010.Conclusion Spatial clustering nature of HFMD incidence between 2008 and 2011 in China appeared to be moderate or high,with the clustered areas a north to south shifting trend.However,further investigation was in need to address this changing trend.

Using exploratory spatial data analysis(ESDA)on the regional distribution of human brucellosis in six provinces of north China: 2004-2007 / 中华流行病学杂志

Based on data related to human brucellosis which was collected from the national notifiable infectious disease reporting system in the 6 provinces(Inner Mongolia,Shanxi,Heilongjiang,Shaanxi,Jilin and Liaoning)of north China from 2004 to 2007,at the county scale.Data would include age and gender standardized mortality ratios(SMRs)while ESDA was including histograms,box plots and box maps,global and local Moran' s I statistics,etc.The global Moran' s I values from 2004 to 2007 were 0.2581,0.4574,0.4457,0.4841,respectively and all with statistically significant differences.Most of local Moran' s I values were significant positive statistically.High-high counties were mainly in the northeast,most of which were pastoral areas,but the farming-pastoral areas and agricultural areas/town had an increasing trend over time.Low-low counties were mainly in the western and southern areas and most of which were agricultural areas/towns.Low-high counties appeared to be rare,mainly around the counties with high incidence,mainly belonged to agricultural areas/towns.The incidence rates of brucellosis in the six provinces of north China had a trend of increase from 2004 to 2007,namely spreading from east to west,from south to north,and from pastoral areas to farming-pastoral areas and agricultural areas/towns.ESDA could be used to develop effective measures for prevention and control of brucellosis.