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The world has paid a heavy price for the pandemic of the emerging respiratory communicable disease, so more concern about communicable disease surveillance and early warning has been aroused. This paper briefly reviews the establishment of the surveillance and early warning system of respiratory communicable diseases in China, discusses its future development and introduces the novel surveillance methods and early warning models for the purpose of establishment of a multi-channel surveillance and multi-dimensional early warning system of communicable diseases in the future and the improvement of the prevention and control of emerging respiratory communicable diseases in China.

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Humanos , Vigilancia de la Población/métodos , Enfermedades Transmisibles/epidemiología , Enfermedades Transmisibles Emergentes/prevención & control , China/epidemiología , Pandemias , Brotes de Enfermedades/prevención & control

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With the expansion of mpox virus infection from endemic to a global epidemic in 2022, the WHO declared that the mpox event constituted a Public Health Emergency of International Concern. Due to the high degree of gene sequence similarity among orthopox viruses and cross-reactive antibodies induced by orthoviruses, smallpox vaccination may affect the immune response induced by mpox virus infection. The analysis of the protective effects of smallpox vaccination against mpox virus infection will help define the focus of prevention and control. In this review, we clarify the protection of the smallpox vaccine against mpox virus infection by analyzing the correlation between smallpox vaccination, immune response status, and clinical data and providing evidence for the prevention, control, and strategies of mpox epidemics.

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Humanos , Viruela/epidemiología , Mpox/tratamiento farmacológico , Vacuna contra Viruela/uso terapéutico , Vacunación , Inmunidad

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Human Respiratory Syncytial Virus (HRSV) is a serious threat to the population health. The elderly are one of the susceptible populations. The prevalence of HRSV in the elderly is generally higher than that in other age groups except children, which has gradually attracted attention in recent years. This paper reviewed the prevalence, common complications and major complications of HRSV in the elderly, briefly expounded the economic burden of HRSV infection, and proposed that attention should be paid to the disease burden of the elderly after HRSV infection, timely treat common complications, so as to reduce the occurrence of adverse survival outcomes and provide scientific evidence for the prevention and control of HRSV infection in the elderly.

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Niño , Humanos , Anciano , Infecciones por Virus Sincitial Respiratorio/epidemiología , Virus Sincitial Respiratorio Humano

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With the outbreak of infectious diseases, more and more attention has been paid to surveillance and early warning work. Timely and accurate monitoring data is the basis of infectious diseases prevention and control. Effective early warning methods for infectious diseases can improve the timeliness and sensitivity of early warning work. This paper briefly introduces the intelligent early warning model of infectious diseases, summarizes the emerging surveillance and early warning methods of infectious diseases, and seeks the possibility of diversified surveillance and early warning in different epidemic stages and different outbreak scenarios of infectious diseases. This paper puts forward the idea of constructing a diversified method system of infectious diseases surveillance and early warning based on multi-stages and multi-scenarios and discusses the future development trend of infectious diseases surveillance and early warning, in order to provide reference for improving the construction level of infectious diseases surveillance and early warning system in China.

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Humanos , Vigilancia de la Población/métodos , Enfermedades Transmisibles/epidemiología , Brotes de Enfermedades/prevención & control , Epidemias , China/epidemiología

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With the outbreak of infectious diseases, more and more attention has been paid to surveillance and early warning work. Timely and accurate monitoring data is the basis of infectious diseases prevention and control. Effective early warning methods for infectious diseases can improve the timeliness and sensitivity of early warning work. This paper briefly introduces the intelligent early warning model of infectious diseases, summarizes the emerging surveillance and early warning methods of infectious diseases, and seeks the possibility of diversified surveillance and early warning in different epidemic stages and different outbreak scenarios of infectious diseases. This paper puts forward the idea of constructing a diversified method system of infectious diseases surveillance and early warning based on multi-stages and multi-scenarios and discusses the future development trend of infectious diseases surveillance and early warning, in order to provide reference for improving the construction level of infectious diseases surveillance and early warning system in China.

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Humanos , Vigilancia de la Población/métodos , Enfermedades Transmisibles/epidemiología , Brotes de Enfermedades/prevención & control , Epidemias , China/epidemiología

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The incidence and spread of emerging infectious diseases are highly uncertain. This paper summarizes the uncertainty and complexity of emerging infectious disease, and suggests that for the response to the varied emerging infectious diseases in the future, it is still necessary for human to take the strategy of constantly strengthening the prevention and control capability and improving various preparedness protocols. For the better response to emerging infectious diseases and protection of people's health and life, the following measures can be taken, paying more attention to the layout of the infectious disease surveillance network, establishing and maintaining the laboratory surveillance network of infectious diseases, establishing and improving a "wartime-peacetime" transition mechanism or system of medical treatment and response, developing and improving the prevention and control plan for emerging infectious diseases, strengthening the training and rehearsal of emerging infectious disease treatment and response, establishing and improving the system for the grading, classification and stockpile of medical supplies for public health emergency response and establishing and maintaining the system of early warning of emerging infectious diseases and technical platform regulations.

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Humanos , Enfermedades Transmisibles/epidemiología , Enfermedades Transmisibles Emergentes/prevención & control , Brotes de Enfermedades/prevención & control , Salud Pública , Incertidumbre

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<p><b>OBJECTIVE</b>To investigate the impact of impoundment and active public health interventions on rodent populations and rodent-borne diseases in the Three Gorges reservoir region from 1997 to 2012.</p><p><b>METHODS</b>Surveillance data from 1997 to 2012 were extracted from the Public Health Surveillance System of The Three Gorges established in 1997. Temporal changes in the incidences of hemorrhagic fever with renal syndrome (HFRS) and leptospirosis, rodent density, pathogen-carrying rates, and their correlations were analyzed.</p><p><b>RESULTS</b>The average indoor and outdoor rodent densities decreased overall from 1997 to 2012. The average densities decreased by 47.72% (from 4.38% to 2.29%) and 39.68% (from 4.41% to 2.66%), respectively, after impoundment (2003-2012) compared with before impoundment (1997-2002). The average annual incidence rates of HFRS and leptospirosis were 0.29/100,000 and 0.52/100,000, respectively, and decreased by 85.74% (from 0.68/100,000 to 0.10/100,000) and 95.73% (from 1.47/100,000 to 0.065/100,000), respectively, after impoundment compared with before impoundment. Incidences of HFRS and leptospirosis appear to be positively correlated with rodent density in the reservoir area.</p><p><b>CONCLUSION</b>This study demonstrated that rodent density and incidences of rodent-borne diseases decreased and were maintained at low levels during construction of the Three Gorges dam. Measures that reduce rodent population densities could be effective in controlling rodent-borne diseases during large-scale hydraulic engineering construction.</p>

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Animales , Distribución Animal , China , Epidemiología , Reservorios de Enfermedades , Infecciones por Hantavirus , Epidemiología , Leptospirosis , Epidemiología , Virología , Densidad de Población , Enfermedades de los Roedores , Epidemiología , Microbiología , Virología , Roedores , Estaciones del Año , Factores de Tiempo , Abastecimiento de Agua , Zoonosis

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AlM: To explore the inhibiting effect of FTY720 on corneal neovascularization ( CNV) of rat.METHODS: MTT assay and cells scratch were adopted to observe hyperplasia of human umbilical vein endothelial cells ( HUVECs ) and cell migration induced by sphingosine-1-phosphate(S1P) after using FTY720 of different concentration. The effect of FTY720 on CNV induced by S1P in a rat corneal micropocket model was detected. 30SD rats were randomly divided into group A, group B and group C with 10 rats per group. S1P and 0μg, 5μg, and 20μg FTY720 controlled-released particles were implanted into the corneal stroma. The growth of CNV and having pathological examination on 12d after the operation was observed. Findings was analyzed by one-way ANOVA.RESULTS: 10, 102 , 103 , and 104 nmol/L FTY720 and HUVECs co-incubate 72h could inhibit cell proliferation (P < 0. 01 ), 24h after the function of 10, 100nmol/L FTY720, it could inhibit S1P-induced cell migration and the ability of restricting cell proliferation and cell migration was enhanced with increasing concentration of FTY720. On 12d, after rat corneal micropocket controlled-release particles was implanted into groups A, B, C, the CNV area were respectively 10. 05±1. 19, 6. 59±0. 95, 2. 70± 0.68mm2(F=145. 155, P<0. 01), group A and group B was statistically different and this was the same case between group B and group C (P<0. 01).CONCLUSlON:FTY720 can inhibit S1P-induced corneal neovascularization.

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<p><b>OBJECTIVE</b>To analyze and further improvement the application of the China Infectious Diseases Automated-alert and Response System (CIDARS) in Guangxi Zhuang Autonomous Region.</p><p><b>METHODS</b>Results related to the amount of signal, proportion of signal responded, time to signal response, manner of signal verification and on each signal of Guangxi in CIDARS from 2009 to 2011 were described. Performance was compared between the periods of pre/ post the adjustment of parameters in CIDARS on December 10, 2010.</p><p><b>RESULTS</b>A total of 29 788 signals were generated on 16 infectious diseases in the system in Guangxi. 100% signals had been responded with the median time to response as 1.5 hours. The average amount of signal per county per week was 1.7;with 624 signals(2.09%)verified as suspected outbreaks preliminarily and 191 outbreaks of 9 diseases were finally confirmed by further field investigation. The sensitivity of CIDARS was 89.25% , and the timeliness of detection was 2.8 d. After adjusting the parameter of CIDARS, the number of signals reduced, and the sensitivity and timeliness of detection improved for most of the diseases.</p><p><b>CONCLUSION</b>The signals of CIDARS were responded timely, and the performance of CIDARS might be improved by adjusting the parameters of early-warning model, which helped enhance the ability of outbreaks-detection for local public health departments. However the current proportion of false positive signals still seemed to be high, suggesting that both the methods and parameters should be improved, according to the characteristics of different diseases.</p>

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Humanos , China , Epidemiología , Control de Enfermedades Transmisibles , Métodos , Enfermedades Transmisibles , Epidemiología , Notificación de Enfermedades , Métodos , Brotes de Enfermedades , Modelos Teóricos , Vigilancia de la Población , Métodos

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Objective To evaluate the therapeutic effect of Gamma knife radiosurgery (GKRS) on patients aged ≥65 years who presented with brain metastasis. Methods The clinical treatment and follow-up data of 134 patients,admitted to and treated with GKRS in our hospital from March 2004 to March 2010,were analyzed.These 134 patients totally underwent 212 GKRS for 403 metastases.The median maximal and marginal doses were (29.3±8.4) Gy and (15.9±4.8) Gy,respectively.Kaplan-Meier survivor analysis was utilized to calculate the median survive time and multivariate analysis was employed to determine the clinical factors influencing the treatment outcome. Results Of the 372 metastasis followed by imaging,complete response was achieved in 66 lesions (17.7％),partial response in 174 lesions (46.8％),no change in 94 lesions (25.3％),and partial progression in 38 lesions (10.2％).Median survival was 10.9 months.Grade of recursive partitioning analysis (RPA),number of tumors,scores of Karnofsky performance scale (KPS) and status of primary malignancies were found to be factors influencing the efficacy (P＜0.05). Conclusion GKRS for patients aged over 65 years with brain metastases is an effective and safe treatment method that appears to improve survival and is helpful in maintaining relative good life quality in selected population

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<p><b>OBJECTIVE</b>To determine the prevalence of urolithiasis in young children fed infant formula (IF) contaminated with melamine, and the association between IF consumption and urolithiasis.</p><p><b>DESIGN</b>A total of 2 733 children < or = 3 years of age on September 1, 2008 in two townships of Gansu Province, China were studied. Cases of urolithiasis were diagnosed by ultrasonography. Milk product consumption was determined by their caregivers. Remaining IF samples were tested for melamine and cyanuric acid.</p><p><b>RESULTS</b>Of 2 733 eligible children in the two townships, 2 186 (80%) were enrolled in our study. Overall, 16.6% (362) of 2 186 children had urolithiasis. The prevalence was 24.6% in children exclusively fed Sanlu brand IF, 9.7% in those fed other IF, and 8.5% in those fed exclusively on other milk products. For children exclusively breast-fed, no urolithiasis was found (P < 0.05). The prevalence of urolithiasis was 11.4% in children fed 400 g of Sanlu IF, rising to 37.5% in children fed over 25 600 g. Of 48 Sanlu IF samples, 91.7% contained melamine (median = 1 800 ppm; range = 45-4 700) and 66.7% contained cyanuric acid (median = 1.2 ppm; range = 0.4-6.3). Melamine was also detected in 22.2% of 36 other brand IF (median = 27.5 ppm, range = 4-50).</p><p><b>CONCLUSIONS</b>Urolithiasis was associated with melamine-contaminated IF. Although one product caused most morbidity, other milk products may have also contributed to the outbreak.</p>

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Preescolar , Humanos , Recolección de Datos , Contaminación de Alimentos , Alimentos Infantiles , Triazinas , Toxicidad , Urolitiasis

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To explore the effect of magnitude and duration on the performance of Cumulative Sum (CUSUM),with simulation method used on the subject after the insertion of 11 outbreak events into baseline data with Poisson distribution.Sensitivity fluctuated from 9.1％ to 100.0％ with specificities higher than 98.6％.Sensitivity was significantly correlated with magnitude,and increased along with the increase of magnitude.However,no significant correlation was observed between sensitivity and duration.A magnitude which was at least 2.6 times higher than that of the mean daily baseline could result in the sensitivity of 100.0％.Time-lag would be improved along with the increase of magnitude.Time between onset and detection of an outbreak was no longer than one day when magnitude was more than 1.8 of the mean daily baseline.In summary,the performance of CUSUM was influenced by magnitude,but not by duration.CUSUM had the advantage of good time-lag and high sensitivity when the outbreak magnitude was more than 2.4 time over the baseline data.

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Objective To reveal the characteristics and stability of the system through the analyzing the surveillance data of respiratory-feverous syndrome via the syndromic surveillance system which was established during the Shanghai World Expo in Pudong New District and provide references for the development and operation optimization on this Mass Gatherings Surveillance Systems.Methods Data used was from the surveillance data of respiratory-feverous syndrome collected from Pudong New District Syndromic Surveillance System,through May 1 to October 31,2010.On the basis of description of data characteristics,correlation analyses were conducted,when compared to the surveillance data of respiratory-feverous syndrome and Pudong influenza-like illness (ILI) used as reference.Comparison of variances on the surveillance data and the report lag time of the earlier and later surveillance periods were also carried out to evaluate the quality and stability of data.Results Reports on the respiratory-feverous syndrome showed a peak in late September with day-of-week effects and holiday effects.Correlation between respiratory-feverous syndrome and ILI was the strongest in the same day (r=0.596,P＜0.05).In the earlier surveillance period from 2010-05-01 to 2010-07-31,the correlation between respiratory-feverous syndrome and ILI was not obvious (r=-0.058,P＞0.05) ; however,the two-time series showed consistent trend with the correlation coefficient as 0.798 (P＜0.05),in the later period from 2010-08-01 to 2010-10-31.In addition,variability of the surveillance data on respiratory-feverous syndrome was less in the later period than in the earlier one,with quality of the report on relatcd data better in the later period.Analyses on the correlations of reference sequence,variability and quality of report indicated that the stability of the later surveillance period was better than the earlier one.Conclusion Only with the operation of syndromic surveillance system for a certain period of time,could data in the system maintain stability.Surveillance data showed both day-of-week effects and holiday effects,suggesting that there was a need to choose early warning models with short baseline data.

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Objective To explore the establishment of animal models of incomplete spinal cord ischemic injury to provide ideal carriers for researching the pathogenesis of incomplete spinal cord ischemic injury.Methods Twenty-four New Zealand rabbits were randomly divided into a control group (n=8) and 2 experimental groups (n=16); control group only underwent sham-operation without inducing spinal cord injury to exclude the influences of anesthesia and surgery on motor evoked potential (MEP); in the experimental groups,spinal cord ischemia injury models were established by the methods of selective ligation of segmental spinal artery from cranio-caudal direction.Baseline MEP after anesthetization were recorded,and the MEP 30 min,2 and 7 d after vascular ligation were noted.Motor function was assessed after narcotic conscious,and 2 and 7 d after vascular ligation.The specimens 7 d after ligation were taken for HE staining.Results The amplitude of MEP in the experimental group having 3 lumbar artery ligation 30 minutes after ligation was significantly different as compared with that in the control group (P＜0.05); no significant differences on the amplitude of MEP were noted between these 2 groups 2 and 7 d after ligation (P＞0.05).Significant differences on the amplitude of MEP were noted between control group and experimental group having 4 lumbar artery ligation 30 min,and 2 and 7 d after ligation (P＜0.05).The latency of all these rabbits showed no significant difference 30 min,and 2 and 7 d after ligation (P＞0.05).The amplitude changes of MEP were accorded with the results of motor function scale.Conclusion Reversible incomplete spinal cord ischemia animal models can be established after 3 lumbar artery ligation; irreversible incomplete spinal cord ischemia animal models can be established after 4 lumbar artery ligation.

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<p><b>OBJECTIVE</b>To explore an effective method for further improving the surgical results of treatment of olfactory groove meningiomas.</p><p><b>METHODS</b>Sixty seven cases of olfactory groove meningiomas were treated by microneurosurgery, among which fifty seven were de novo cases, eight were recurrent tumors and the other two re-recurrent cases. Modified Derome approach was used in 12 cases, bilateral subfrontal approach in 28 cases, modified pterional approach in 21 cases and unilateral subfrontal approach in six cases. Tumors were resected microsurgically with radical removal of invaded dura, bone, and paranasal sinus mucosa. Reconstruction was performed in patients with skull base defect.</p><p><b>RESULTS</b>Simpson grade I removal was accomplished in 59 cases, grade II in seven cases and grade IV in one case. Among 57 patients with de novo tumor, Simpson I resection was accomplished in 54 cases. Postoperative rhinorrhea and intracranial infection occurred in one case and was cured after temporal lumbar CSF drainage and antibiotic therapy. Two patients (2.9%) died within one month after operation, i.e.one aged patient of heart failure and the other of severe hypothalamus complication. Forty seven patients (72.3%) were followed up from one to ten years with an average of five years and four months. With the exception of two cases died, among the alive 45 patients, there were only three patients with tumor recurrence, which had undergone Simpson II or IV tumor resection. No recurrence was found in cases with Simpson I tumor removal. Previous blurred vision was not improved in three patients, hemiparalysis in two patients, and the other patients recovered well, resuming previous jobs or being able to take care themselves.</p><p><b>CONCLUSIONS</b>Total tumor removal (Simpson I) should be the surgical goal for treatment of olfactory groove meningiomas, especially for de novo cases. An appropriate approach is fundamental in the effort to remove an OGM totally. Appropriate anterior skull base reconstruction with vascularized material is important and mandatory.</p>

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Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rinorrea de Líquido Cefalorraquídeo , Duramadre , Patología , Cirugía General , Estudios de Seguimiento , Imagen por Resonancia Magnética , Neoplasias Meníngeas , Diagnóstico , Patología , Cirugía General , Meningioma , Diagnóstico , Patología , Cirugía General , Microcirugia , Métodos , Recurrencia Local de Neoplasia , Senos Paranasales , Patología , Cirugía General , Procedimientos de Cirugía Plástica , Base del Cráneo , Patología , Cirugía General

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Objective To better understand and measure the status of hepatitis C virus (HCV) infection, we conducted a sero-epidemiological study using the remaining blood samples and data of the nationwide survey of hepatitis B in Chinese residents which was carried out in 2006.Methods The anti-HCV reagent was screened out from the reagents by the HCV infection blood serum plate with anti-HCV positives or negatives. This plate recognized the Murex 3.0 and Ortho 3.0 reagents as gold standards. Anti-HCV in the blood samples were tested using this reagent and confirmed by Chiron HCV RIBA 3.0 reagents. Results Among the population aged 1 year to 59 year-olds, the overall prevalence rate of anti-HCV was 0.43％ (95％CI: 0.33％-0.53％ ), with the rates of anti-HCV among males and females as 0.46％ and 0.40％, respectively. The prevalence rate of anti-HCV in urban area was 0.43％,and in rural area it was 0.43％. The prevalence rate of anti-HCV in the Eastern, Middle and Western areas were 0.37％ (95％ CI: 0.21％-0.53％ ) , 0.67％ (95％ CI: 0.40％-0.94％ ) and 0.31％ (95％CI: 0.20％-0.42％ ) respectively. The prevalence rates of anti-HCV for the three areas did not show significant differences, statistically. The prevalence rate of anti-HCV in the South and North areas were 0.29％(95％CI:0.21％-0.52％) and 0.53％ (95％CI:0.38％-0.64％)respectively. Conclusion Our data revealed that China was in the low prevalence area for hepatitis C infection and the results also suggested that the comprehensive measures for HCV control and prevention had been successfully achieved in the country.

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Objective To evaluate the impact on the health status of population in the area where the ‘Three Gorges Reservoir Water Storage Project' had been operated and to provide references for the development of related disease control strategies.Methods In the Three Gorges Reservoir Area,17 towns/streets in nine counties were chosen as surveillance points.Data on surveillance program would include infectious diseases,birth,death,biological agents etc.Methods related to time and spatial analysis and the comparison on pre- and post- water storage were used to analyze and describe the long-term changing trend of meteorological index,distribution of biological agent and diseases,and human health status.Relationships between number of infectious diseases and media biological density and meteorological parameters were also analyzed.Results When the water storage program came into being in 2003,the indoor (2.22％) and outdoor (2.76％) densities of rats were significantly lower than pre-water storage period (indoor 4.38％ vs.outdoor 4.43％) and the annual average density of mosquito (35.09 mosquitoes per room and per hour) was also lower than before (54.24 mosquitoes per room and per hour).The incidence rates of encephalitis B,malaria,leptospirosis,and hemorrhagic fever had reduces 22.88％,84.85％,95.03％ and 81.82％ than before.The incidence rates of malaria,leptospirosis,and hemorrhagic fever were all below 0.4/100 000 and the incidence of encephalitis B was below 2/100 000.The average infant mortality was 11.83‰.The annual infant mortalities,after adjusted by missing report numbers,were between 13.07‰ and 23.88‰ which were lower than the national annual average level.The thirteen year standard mortalities were 3.77‰-5.12‰,with the total rate lower than the national average level in the same years.Conclusion In 2003,the incidence rates of malaria,encephalitis B,leptospirosis,epidemic hemorrhagic fever kept going down in the surveillance sites in the Three Gorges Reservoir Area,and the overall population's health status was well enough to show that there was no negative impact on the health status of population living in the area after the water storage project was inplemented.

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Objective To compare the performance of aberration detection algorithm for infectious disease outbreaks, based on two different types of baseline data. Methods Cases and outbreaks of hand-foot-and-mouth disease (HFMD) reported by six provinces of China in 2009 were used as the source of data. Two types of baseline data on algorithms of C1 ,C2 and C3 were tested, by distinguishing the baseline data of weekdays and weekends. Time to detection (TTD) and false alarm rate (FAR) were adopted as two evaluation indices to compare the performance of 3 algorithms based on these two types of baseline data. Results A total of 405 460 cases of HFMD were reported by 6 provinces in 2009. On average,each county reported 1.78 cases per day during the weekdays and 1.29 cases per day during weekends, with significant difference (P<0.01) between them. When using the baseline data without distinguish weekdays and weekends, the optimal thresholds for C1, C2 and C3 was 0.2,0.4 and 0.6 respectively while the TTD of C1,C2 and C3 was all 1 day and the FARs were 5.33% ,4.88% and 4.50% respectively. On the contrast, when using the baseline data to distinguish the weekdays and weekends, the optimal thresholds for C1, C2 and C3 became 0.4,0.6 and 1.0 while the TTD of Cl,C2 and C3 also appeared equally as 1 day.However, the FARs became 4.81%,4.75% and 4.16% respectively, which were lower than the baseline data from the first type. Conclusion The number of HFMD cases reported in weekdays and weekends were significantly different, suggesting that when using the baseline data to distinguish weekdays and weekends, the FAR of C1, C2 and C3 algorithm could effectively reduce so as to improve the accuracy of outbreak detection.

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Objective To compare the different thresholds of 'moving percentile method' for outbreak detection in the China Infectious Diseases Automated-alert and Response System (CIDARS). Methods The thresholds of P50, P60, P70, P80 and P90 were respectively adopted as the candidates of early warning thresholds on the moving percentile method. Aberration was detected through the reported cases of 19 notifiable infectious diseases nationwide from July 1,2008 to June 30,2010. Number of outbreaks and time to detection were recorded and the amount of signals acted as the indicators for determining the optimal threshold of moving percentile method in CIDARS. Results The optimal threshold for bacillary and amebic dysentery was P50. For non-cholera infectious diarrhea,dysentery, typhoid and paratyphoid, and epidemic mumps, it was P60. As for hepatitis A, influenza and rubella, the threshold was P70, but for epidemic encephalitis B it was P80. For the following diseses as scarlet fever, typhoid and paratyphoid, hepatitis E, acute hemorrhagic conjunctivitis, malaria, epidemic hemorrhagic fever, meningococcal meningitis, leptospirosis, dengue fever, epidemic endemic typhus,hepatitis C and measles, it was P90. When adopting the adjusted optimal threshold for 19 infectious diseases respectively, 64 840(12.20%)signals had a decrease, comparing to the adoption of the former defaulted threshold(P50)during the 2 years. However, it did not reduce the number of outbreaks being detected as well as the time to detection, in the two year period. Conclusion The optimal thresholds of moving percentile method for different kinds of diseases were different.Adoption of the right optimal threshold for a specific disease could further optimize the performance of outbreak detection for CIDARS.

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Objective To understand the effectiveness of China Infectious Disease Automated-alert and Response System(CIDARS)for outbreak detection at the regional level.Methods Two counties in Hunan province(Yuelu and Shuangfeng county)and two counties in Yunnan province(Xishan and Gejiu county)were chosen as the study areas. Data from CIDARS were analyzed on the following items: reported cases, warning signals, the time interval of signal response feedback, way of signal verification, outcome of signal verification and field investigation, from July 1,2008 to June 30,2010. Results In total, 12 346 cases from 28 kinds of diseases were reported,and 2096 signals of 19 diseases were generated by the system, with an average of 4.94 signals per county per week. The median of time interval on signal verification feedback was 0.70 hours(P25-P75:0.06-1.29 h)and the main way of signal preliminary verification was through the review of surveillance data(account for 63.07%). Among all the signals, 34 of them(1.62%)were considered to be related to suspected events via the preliminary verification at the local level. Big differences were found to have existed on the proportion of signals related to the suspected events of the total signals among the four counties, with Shuangfeng county as 4.71%, Yuelu county as 1.88%, Gejiu county as 0.95% and Xishan county as 0.58%. After an indepth study on the fields of suspected events, 12outbreaks were finally confirmed, including 5 on rubella, 4 on mumps, 2 on influenza and 1 on typhoid fever. Conclusion CIDARS could be used to assist the local public health institutions on early detection of possible outbreaks at the early stage. However, the effectiveness was different depending on the regions and diseases.