ABSTRACT
Objective To optimize the warning threshold values of common communicable diseases in Gansu province,and improve the early warning effect.Method An early warning model was set up for influenza,scarlet fever,other infectious diarrheal diseases,dysentery,typhoid and paratyphoid,viral hepatitis type E and hand foot and mouth disease (HFMD) respectively in Gansu by using the moving percentile method and cumulative sum method.By calculating the sensitivity,specificity,predictive value of positive test,predictive value of negative test,Youden'index and receiver-operating characteristic curve,the optimum early warning threshold values for communicable diseases in Gansu were selected.Results The optimum early warning boundary values of influenza,scarlet fever,other infectious diarrheal diseases,dysentery,typhoid and paratyphoid,and viral hepatitis type E were P90,P80,P95,P90,P80 and P90 respectively.The optimum early warning parameters of HFMD were k =1.2,H=5σ.Under the optimum early warning boundary values/parameters,the early warning sensitivities of influenza,scarlet fever,other infectious diarrheal diseases,dysentery,typhoid and paratyphoid,viral hepatitis type E and HFMD were 86.67％,100.00％,91.67％,100.00％,100.00％,100.00％ and 100.00％,the specificities were 86.49％,62.22％,75.00％,100.00％,97.92％,89.13％ and 74.47％.The predictive values of positive test were 72.22％,29.17％,52.38％,100.00％,80.00％,54.55％ and 29.41％,and the predictive values of negative test were 94.12％,100.00％,96.77％,100.00％,100.00％,100.00％ and 100.00％,and the Youden'indexes were 0.73,0.62,0.67,1.00,0.98,0.89 and 0.74.Receiver-operating characteristic curve showed that the values/parameters of this warning boundary were the points closest to the upper left of the coordinate diagram.Conclusion The early warning thresholds of influenza,other infectious diarrheal diseases,dysentery and hepatitis E in Gansu may be raised appropriately and the early warning parameters of HFMD need to be adjusted to improve the effectiveness of early warning.
ABSTRACT
Objective To optimize the warning threshold values of common communicable diseases in Gansu province,and improve the early warning effect.Method An early warning model was set up for influenza,scarlet fever,other infectious diarrheal diseases,dysentery,typhoid and paratyphoid,viral hepatitis type E and hand foot and mouth disease (HFMD) respectively in Gansu by using the moving percentile method and cumulative sum method.By calculating the sensitivity,specificity,predictive value of positive test,predictive value of negative test,Youden'index and receiver-operating characteristic curve,the optimum early warning threshold values for communicable diseases in Gansu were selected.Results The optimum early warning boundary values of influenza,scarlet fever,other infectious diarrheal diseases,dysentery,typhoid and paratyphoid,and viral hepatitis type E were P90,P80,P95,P90,P80 and P90 respectively.The optimum early warning parameters of HFMD were k =1.2,H=5σ.Under the optimum early warning boundary values/parameters,the early warning sensitivities of influenza,scarlet fever,other infectious diarrheal diseases,dysentery,typhoid and paratyphoid,viral hepatitis type E and HFMD were 86.67％,100.00％,91.67％,100.00％,100.00％,100.00％ and 100.00％,the specificities were 86.49％,62.22％,75.00％,100.00％,97.92％,89.13％ and 74.47％.The predictive values of positive test were 72.22％,29.17％,52.38％,100.00％,80.00％,54.55％ and 29.41％,and the predictive values of negative test were 94.12％,100.00％,96.77％,100.00％,100.00％,100.00％ and 100.00％,and the Youden'indexes were 0.73,0.62,0.67,1.00,0.98,0.89 and 0.74.Receiver-operating characteristic curve showed that the values/parameters of this warning boundary were the points closest to the upper left of the coordinate diagram.Conclusion The early warning thresholds of influenza,other infectious diarrheal diseases,dysentery and hepatitis E in Gansu may be raised appropriately and the early warning parameters of HFMD need to be adjusted to improve the effectiveness of early warning.
ABSTRACT
Objective To explore the etiology and epidemiological characteristics of fever and rash syndrome a mong children under the age of five years in Northwest China from 2009 to 2015.Methods Descriptive epidemiological analysis was conducted based on the monitoring data in sentinel hospitals,which was from the information management system of national infectious disease monitoring from 2009 to 2015 in Gansu,Qinghai,Inner Mongolia and Xinjiang.Results The results showed that the major pathogens of fever and rash syndrome among children under the age of five years were enterovirus,measles virus,varicella-zoster virus (VZV) and rubella virus.The major pathogens among children in the age group of 0-years and in the age group of 1-5 years were measles virus and enteroviruses,respectively.Among the positive cases of enterovirus,the positive detectable rates of human enterovirus 71 (EV71) and coxsackie A16 (CA16) were 47.18％ and 45.59％,respectively.The incidences of enterovirus and measles virus infection were mainly concentrated on May to July and March to May,respectively.Conclusions The major pathogens of fever and rash syndrome among children under the age of five years in Northwest china were enterovirus and measles virus with seasonal epidemic characteristics.Therefore,the prevention and control of measles and hand-foot-mouth disease should be strengthened.
ABSTRACT
Objective To study the epidemiologic characteristics of influenza in Gansu province of China and to optimize the related vaccination program.Methods Weekly influenza surveillance data from the first week of 2010 to the fortieth week of 2016 were collected,in Gansu province.x2 test was used to compare the differences of nucleic acid positive rate and the virus types in the four seasons.Time series seasonal decomposition (TSSD) was used to explore seasonal patterns and characteristics of influenza epidemics in Gansu.Results 59 791 specimens were tested,with 8 501 positive for influenza virus and positive rates as 14.22％.Types A(H1N1)pdm09,A(H3N2) and type B were accounted for 98.76％ of all the positive specimens.Proportions of the positive rate of influenza virus appeared in spring,summer,autumn and winter were 15.12％,0.98％,4.02％ and 24.26％ respectively.The predominant type of virus in autumn and winter was A(H3N2),with B mainly in spring.Influenza in Gansu province showed typical single-peak type distribution,with epidemic peak appeared from December to next January.The type A(H3N2) related peak appeared the earliest,followed by A(H1N1)pdm09,with type B the latest.Conclusions Peaks and the duration of influenza seasonal epidemics were related to the types of dominant strains.Annual influenza vaccination campaigns should start in October,to provide effective protection during the epidemic period.
ABSTRACT
Objective To study the epidemiologic characteristics of influenza in Gansu province of China and to optimize the related vaccination program.Methods Weekly influenza surveillance data from the first week of 2010 to the fortieth week of 2016 were collected,in Gansu province.x2 test was used to compare the differences of nucleic acid positive rate and the virus types in the four seasons.Time series seasonal decomposition (TSSD) was used to explore seasonal patterns and characteristics of influenza epidemics in Gansu.Results 59 791 specimens were tested,with 8 501 positive for influenza virus and positive rates as 14.22％.Types A(H1N1)pdm09,A(H3N2) and type B were accounted for 98.76％ of all the positive specimens.Proportions of the positive rate of influenza virus appeared in spring,summer,autumn and winter were 15.12％,0.98％,4.02％ and 24.26％ respectively.The predominant type of virus in autumn and winter was A(H3N2),with B mainly in spring.Influenza in Gansu province showed typical single-peak type distribution,with epidemic peak appeared from December to next January.The type A(H3N2) related peak appeared the earliest,followed by A(H1N1)pdm09,with type B the latest.Conclusions Peaks and the duration of influenza seasonal epidemics were related to the types of dominant strains.Annual influenza vaccination campaigns should start in October,to provide effective protection during the epidemic period.
ABSTRACT
<p><b>OBJECTIVE</b>To understand the hot/cold spots and the spatial-temporal clustering of hepatitis B in Gansu province during 2009-2014 by using spatial statistics, and provide scientific evidence for the prevention and control of hepatitis B.</p><p><b>METHODS</b>The spatial hot/cold spots and its trend, and the time frame and areas of its spatial-temporal clustering of hepatitis B in Gansu were analyzed by using the county specific incidence of hepatitis B from 2009 to 2014 and spatial statistical software GeoDa and SatScan.</p><p><b>RESULTS</b>The incidences of hepatitis B from 2009 to 2014 in Gansu were spatial autocorrelated respectively. Local G scan statistics indicated that the number of hot spots was in decline in Hexi area, while the hot spots was in increase in Linxia Hui autonomous prefecture and Gannan Tibetan autonomous prefecture. There was no obvious pattern in cold spots. Temporal-spatial scan statistics showed that the areas with high hepatitis B incidence most likely clustered in Hexi area during 2009-2011, and the areas with low hepatitis B incidence most likely clustered in eastern Gansu during 2012-2014.</p><p><b>CONCLUSIONS</b>The spatial and temporal clustering of hepatitis B was observed in Gansu from 2009 to 2014. The number of hot spots in Hexi area was in decline, while the numbers of hot spots in Linxia and Gannan were in increase, suggesting that the hepatitis B control and prevention in these areas should be strengthened.</p>
Subject(s)
Humans , China , Epidemiology , Cluster Analysis , Epidemiological Monitoring , Hepatitis B , Epidemiology , Incidence , Software , Spatio-Temporal AnalysisABSTRACT
<p><b>OBJECTIVE</b>To explore the appropriate early warning method for influenza epidemic in Gansu province.</p><p><b>METHODS</b>By using simple control chart, moving percentile method, exponential smoothing method and cumulative sum control chart method, the annual incidence data of influenza-like illness in Gansu province during 2014-2015 were analyzed, and the sensitivities, specificities, positive predictive values, Jorden indexes and Kappa values of the 4 methods were evaluated and compared.</p><p><b>RESULTS</b>The 2014-2015 seasonal influenza epidemic occurred in the fiftieth week of 2014 in Gansu, and the epidemic peak lasted for 6 weeks. Cumulative sum control chart method had the best early warning effect with the sensitivity of 66.67% and specificity of 93.48%.</p><p><b>CONCLUSION</b>It is feasible to use cumulative sum control chart method to give early warning of influenza epidemic in Gansu.</p>
Subject(s)
Humans , China , Epidemiology , Disease Notification , Methods , Epidemics , Feasibility Studies , Influenza, Human , Epidemiology , SeasonsABSTRACT
<p><b>OBJECTIVE</b>To study the time-space distribution of viral hepatitis C in Gansu province during 2009-2013, using the time-space statistics.</p><p><b>METHODS</b>Using Geoda to analysis the univariate Moran's I and univariate local Moran's I while using SaTScan to detect the time-space gathering areas.</p><p><b>RESULTS</b>There was spatial autocorrelation on incidence of hepatitis C noticed in Gansu during 2009-2013. The hot spots areas were counties as Jinchang, Wuwei, Zhangye and Lanzhou. Cold spot areas would include counties as Dingxi, Longnan, Pingliang, Gannan, Jiuquan, Qingyang, Baiyin and Tianshui. There were time-space gathering areas nitoced, during 2009-2010. Qinzhou and Maiji counties belonged to high incidence gathering areas. Lintao and Linxia were of low incidence gathering areas. In 2011-2013, high incidence gathering area would include counties as Zhangye, Jinchang, Wuwei Lanzhou and Baiyin while low incidence gathering areas would include counties as Dingxi, Tianshui, Pingliang, Longnan and Qingyang.</p><p><b>CONCLUSION</b>There appeared time-space gathering of hepatitis C in Gansu province during 2009-2013. High and low gathering areas varied with time and high incidence gathering area mainly distributed in the western and central areas of Gansu province.</p>
Subject(s)
Humans , China , Epidemiology , Hepatitis C , Epidemiology , Incidence , Spatio-Temporal AnalysisABSTRACT
Objective To detect the spatial temporal distribution of mumps in Gansu by means of spatial statistics.Methods The county-based incidence of mumps from 2009 to 2013 was used to calculate the global Moran' s I and local G statistics, and analyze its spatial temporal distribution characteristics.Results The incidence of mumps in Gansu were spatial auto-correlated from 2009 to 2013 respectively (P＜0.001), and the hot spots were mainly distributed in Hexi area,while the cold spots were distributed in Tianshui, Longnan and Qingyang.Spatial temporal analysis showed that the high incidence of mumps was most likely to be detect in Hexi area (RR=3.05, LLR=4 670.995, P＜0.001), and the low incidence was most likely to be detect in Longdong area (RR=0.36,LLR=1 980.686,P＜0.001).Conclusion The spatial and spatial temporal clustering of mumps existed in Gansu from 2009 to 2013, the results can be used in the development of mumps prevention and control measure in Gansu.
ABSTRACT
<p><b>OBJECTIVE</b>To understand the spatial-temporal specific incidence of pulmonary tuberculosis (TB) in Gansu.</p><p><b>METHODS</b>The county-based incidence of pulmonary TB in Gansu from 2009 to 2013 was used to calculate Moran's I and G statistics, and analyze the spatial-temporal distribution of areas with different pulmonary TB incidences.</p><p><b>RESULTS</b>The spatial correlation in incidence of pulmonary TB was found in Gansu from 2009 to 2013 (P<0.001), and the hot spot areas were mainly in Hexi area, Linxia, part of Dingxi, while the cold spot areas were in Lanzhou, part of Dingxi, Tianshui, Pingliang and Qingyang. Spatial-temporal analysis showed that the clustering of high pulmonary TB incidence areas were most likely in the Hexi area during 2009-2010 (LLR=3,031.10, RR=2.27, P<0.001), and the clustering of low pulmonary TB incidence areas were most likely in Lanzhou during 2011-2013 (LLR=1,545.52, RR=0.37, P<0.001).</p><p><b>CONCLUSION</b>The analysis on spatial and spatial-temporal specific incidences of pulmonary TB in Gansu from 2009 to 2013 indicated that Hexi area is the key area in pulmonary TB prevention and control in Gansu.</p>
Subject(s)
Humans , Biometry , China , Epidemiology , Cluster Analysis , Incidence , Spatio-Temporal Analysis , Tuberculosis, Pulmonary , EpidemiologyABSTRACT
<p><b>OBJECTIVE</b>The purpose of this study was to explore the spatial distribution and spatial clustering of hand-foot-mouth disease (HFMD) in Gansu, 2012.</p><p><b>METHODS</b>Spatial autocorrelation and Spatial scanning analysis were used to conduct spatial statistical analyses for the HFMD at the county/district level.</p><p><b>RESULTS</b>HFMD cases did not show a random distribution but with significant spatial aggregation. When Local Autocorrelation analysis was applied at the county/district level, with nine hot spot areas as Jiayuguan, Yumen, Dunhuang, Jinta, Suzhou, Chengguan, Anning, Xigu and Gaolan, were discovered. Four statistically significant HFMD clusters were identified by spatial scan statistics.</p><p><b>CONCLUSION</b>HFMD was noticed geographically clustered in Gansu in 2012. Results from this study indicated that the spatial autocorrelation and spatial scanning analysis could effectively detect the areas which presenting significant clusters. Cluster Detection System (CDS) could provide evidence for the development of an effective measure concerning the prevention and control of HFMD.</p>