RESUMO
Objective To investigate the spatio-temporal distribution characteristics of Oncomelania hupensis snail habitats in three cities of Suzhou, Wuxi and Changzhou along the Taihu Lake region, so as to provide technical supports for establishing a sensitive and highly effective surveillance and forecast system for schistosomiasis. Methods Snail distribution data were collected from Suzhou, Wuxi and Changzhou cities from 1950 to 2018, and the changing trend for snail habitats were described over years. In addition, the clusters of snail habitats were detected using Kernel density analysis and SaTScan space-time scan analysis. Results The number of snail habitats appeared a single-peak distribution in Suzhou, Wuxi and Changzhou cities from 1950 to 2018, which peaked in 1970 and then declined rapidly. There were 62.68% of snail habitats eliminated within 10 years after identification, of which 38.24% were eliminated at the year of identification. Kernel density analysis and SaTScan space-time scan analysis revealed that high-density clusters of snail habitats were mainly distributed in Kunshan City, Wuzhong District and Xiangcheng District from 1970 to 1980, and in Yixing City in 1990; since then, the clusters gradually shrank, and overall appeared a move from northeast to west of Taihu Lake. A total of 4 new clusters were detected after 1970, as revealed by space-time scanning of snail habitats. In current snail habitats, emerging snail habitats are mainly identified in Huqiu District (Dongzhu Town), Wuzhong District (Guangfu Town), Taicang City (Shaxi Town) and Jintan District, and re-emerging snail habitats are scattered in 7 districts. Conclusions The distribution of snail habitats are spatio-temporal aggregation in Suzhou, Wuxi and Changzhou cities. The monitoring and prediction of emerging and re-emerging snail habitats are the key points in the future.
RESUMO
Objective To analyze the spatiotemporal characteristics of HIV/AIDS in Shandong province,2009-2015.Methods Data on HIV/AIDS between 2009 and 2015 were derived from the Shandong provincial HIV/AIDS Comprehensive Response Information Management System at the end of 2015.All the data were geographically referenced based on 139 spatial units in the related counties of Shandong province.Electronic maps were obtained from China CDC.Global Moran's I statistics and LISA statistics were used to detect the global and local spatial distribution patterns of HIV/AIDS in Shandong.Space-time scan statistics method,based on the Poisson Model,was used to detect the space-time clusters of HIV/AIDS.Results A total of 9 144 HIV/AIDS cases were reported during 2009-2015 in Shandong province.The scope of spatial distribution on HIV/AIDS expanded annually and concentrated in certain areas.Spatial distribution of HIV/AIDS in 2009 was randomized,and results showed spatial autocorrelation at the county level,during 2010-2015.Spatial hotspot-clusters mainly appeared in Tianqiao,Shizhong and Licheng districts of Jinan city,and Shinan,Laoshan districts of Qingdao city.Results from the Space-time scan analysis identified 5 spatiotemporal clusters in 2013-2015,including 1 most likely cluster and 4 secondary clusters which involving Lixia,Shizhong,Huaiyin and Tianqiao districts of Jinan city (RR=11.29,LLR=1 592.84,P＜0.001).The covered counties in secondary clusters appeared in Shinan,Shibei and Licang districts of Qingdao city (RR=7.35,LLR=682.40,P＜0.001),Weicheng and Kuiwen districts of Weifang city (RR=7.33,LLR=363.49,P＜0.001),Zhifu and Laishan districts of Yantai city (RR=7.66,LLR=117.63,P＜0.001),Zhoucun and Zhangdian districts of Zibo city (RR =6.09,LLR=268.68,P＜0.001)respectively.Conclusion HIV/AIDS cases in Shandong province appeared clustering features in both dimensions of time and space.Prevention efforts were needed to focus on HIV/AIDS highly clustered areas,such as Jinan city,Qingdao city,Zibo city,Weifang city and Yantai city.
RESUMO
Objective To analyze the spatiotemporal characteristics of HIV/AIDS in Shandong province,2009-2015.Methods Data on HIV/AIDS between 2009 and 2015 were derived from the Shandong provincial HIV/AIDS Comprehensive Response Information Management System at the end of 2015.All the data were geographically referenced based on 139 spatial units in the related counties of Shandong province.Electronic maps were obtained from China CDC.Global Moran's I statistics and LISA statistics were used to detect the global and local spatial distribution patterns of HIV/AIDS in Shandong.Space-time scan statistics method,based on the Poisson Model,was used to detect the space-time clusters of HIV/AIDS.Results A total of 9 144 HIV/AIDS cases were reported during 2009-2015 in Shandong province.The scope of spatial distribution on HIV/AIDS expanded annually and concentrated in certain areas.Spatial distribution of HIV/AIDS in 2009 was randomized,and results showed spatial autocorrelation at the county level,during 2010-2015.Spatial hotspot-clusters mainly appeared in Tianqiao,Shizhong and Licheng districts of Jinan city,and Shinan,Laoshan districts of Qingdao city.Results from the Space-time scan analysis identified 5 spatiotemporal clusters in 2013-2015,including 1 most likely cluster and 4 secondary clusters which involving Lixia,Shizhong,Huaiyin and Tianqiao districts of Jinan city (RR=11.29,LLR=1 592.84,P＜0.001).The covered counties in secondary clusters appeared in Shinan,Shibei and Licang districts of Qingdao city (RR=7.35,LLR=682.40,P＜0.001),Weicheng and Kuiwen districts of Weifang city (RR=7.33,LLR=363.49,P＜0.001),Zhifu and Laishan districts of Yantai city (RR=7.66,LLR=117.63,P＜0.001),Zhoucun and Zhangdian districts of Zibo city (RR =6.09,LLR=268.68,P＜0.001)respectively.Conclusion HIV/AIDS cases in Shandong province appeared clustering features in both dimensions of time and space.Prevention efforts were needed to focus on HIV/AIDS highly clustered areas,such as Jinan city,Qingdao city,Zibo city,Weifang city and Yantai city.
RESUMO
Objective To learn the spatial and temporal patterns of primary syphilis and secondary syphilis in Shenzhen and to provide evidence for carrying out further research on syphilis.Methods Primary syphilis and secondary syphilis cases among residents in Shenzhen between 2005and 2009(n=11 303) were geocoded at street office level (n=55) based on residence at the time of diagnosis. Both spatial and space-time scan statistics were used to identify clusters of street office by using SaTScan software. Results In the purely spatial analyses, clusters were seen in the junction of the Baoan district and Nanshan district (Xinan, Xixiang, Nanshan and Nantou street office) and in the region near Hong Kong (Dongmen, Shekou, and Futian street office), as well as in the other streets where entertainment industry was relatively developed (Longhua, Huafu, Huangbei and Cuizu street office). The clusters had not changed much in the first four years, but nine clusters appeared in 2009.Annually, the most likely clusters were located in Longhua (2005, P≤0.001, RR=3.34), Bamboo (2006, P≤0.001, RR=9.59), Huafu (2007, 2008 years, P≤0.001, RR values were 4.18 and 4.75)and Cuizu (2009, P≤0.001, RR=8.02). In the space-time scan analysis, we found 16 significant clusters, which were similar to the pure spatial analyses. However, regional difference were also found, with the most likely cluster was the Guiyuan street office in 2006. Conclusion Spatial and space-time scan statistics seemed to be effective ways in describing the circular disease clusters. We have had a better understanding on spatial and temporal patterns of primary syphilis and secondary syphilis in Shenzhen through spatial and space-time scan statistics of syphilis surveillance data in the recent years. The changes of spatial and temporal patterns of primary syphilis and secondary syphilis were also described by SaTScan software, which also provided useful reference for the preventive strategies on sexually transmitted diseases as well as on HIV. Useful information was also provided for financial investment and cost-effective studies.