Colorectal cancer and asbestos exposure-an overview.

The relationship between colorectal cancer and asbestos exposure has not been fully clarified. This study aimed to determine the associations between asbestos exposure and colorectal cancer. We performed a meta-analysis to quantitatively evaluate this association. A fixed effects model was used to summarize the relative risks across studies. Sources of heterogeneity were explored through subgroup analyses and meta-regression. We analyzed the dose-effect relationship using lung cancer standardized mortality ratio (SMR) and the risk of mesothelioma as a percent (%) as exposure surrogates. A total of 47 cohort studies were included. We identified 28 incidence cohort studies from 17 separate papers and extracted colorectal cancer standardized incidence ratio (SIR). Cancer mortality data were extracted from 19 separate cohorts among 13 papers. The overall colorectal cancer SMR for synthesis cohort was 1.07 (95% CI 1.02-1.12). Statistically significant excesses were observed in exposure to mixed asbestos (SMR/SIR=1.07), exposure to production (SMR/SIR=1.11), among asbestos cement workers (SMR/SIR=1.18) and asbestos textile workers (SMR/SIR=1.11). Additionally, we determined that the SMR for lung cancer increased with increased exposure to asbestos, as did the risk for colorectal cancer. This study confirms that colorectal cancer has a positive weak associations with asbestos exposure.

[The Relationship of Polymorphisms in Interleukin 17A Gene, Interleukin 17F Gene and the Pulmonary Inflammation Risk in Dust Exposed Workers in a Chinese Population].

OBJECTIVES: To investigate the polymorphisms in interleukin 17A IL-17A) and interleukin 17F (IL-17F) and their relationship with pulmonary inflammation risk of dust exposed workers. METHODS: A case-control study among 193 subjects, including 67 subjects in case group and 126 in control group was conducted. PCR-RFLP was applied to genotype IL-17A (G-197A) and IL-17F (7488T/C). Logistic regression analysis was used to determine the effects of IL-17A (G-197A) and IL-17F (7488T/C) on the lung inflammation risk in dust exposed workers. RESULTS: The genotypes analysis showed that the proportions of IL-17A (G-197A) A/A, A/G and G/G were 42 (21.76%), 95 (49.22%), 56 (29.02%) in 193 cases, respectively, and the IL-17F (7488T/C) T/T, T/C and C/C genotypes were 128 (66.32%), 54 (28.98%), 11 (5.70%), respectively. The frequency distribution of each genotype was consistent with the Hardy-Weinberg equilibrium fixed law. The ratio of IL-17A (G-197A) A/A in the case group was lower than that of control group ( P<0.05), while the G/G and A/G genotypes were higher than that of control group ( P<0.05). Furthermore, the genotypes of IL-17A (G-197A) A/G (OR=5.03, P<0.01) and G/G(OR=3.35, P<0.05) were associated with an increased risk of lung inflammation in workers exposed to dust. The frequency distribution difference of IL-17F (7488T/C) T/T, T/C and C/C genotypes in the cases and control group was unobvious ( P>0.05). CONCLUSIONS: Under the same dust concentration, the dust exposed workers carrying IL-17A (G-197A) A/G, G/G genotypes are more susceptible to pulmonary inflammation in the southwest of China.

Risk factors for death in children with severe hand, foot, and mouth disease in Hunan, China.

BACKGROUND: In recent years, outbreaks of hand, foot, and mouth disease (HFMD) have increased throughout East and Southeast Asia, especially in mainland China. The disease now presents as an increasingly serious public health threat in China. METHODS: A case-control study was designed to examine risk factors associated with death from severe HFMD. A total of 553 severe HFMD cases were collected from the National Surveillance System. RESULTS: Multifactorial logistic regression was used to analyse independent associations between potential influence factors and death from severe HFMD. We found that the migrants were more likely to die from severe HFMD than the resident population (OR = 3.07, 95%CI: 1.39-8.32). Additionally, the children whose first visit was to a village-level clinic had a high risk of death from severe HFMD. Patients with EV71 infection or symptoms of convulsion, dyspnoea, cyanosis, coolness of extremities, and vomiting had an increased risk of death from severe HFMD. While breastfeeding children, having a confirmed diagnosis at the first visit to the hospital and with symptom of hyperarousal were identified as protective factors for death from severe HFMD. CONCLUSIONS: To reduce the mortality from severe HFMD, doctors and health care providers need to pay attention to the patients with EV71 infection or with symptoms of convulsion, dyspnoea, cyanosis, coolness of extremities, and vomiting. Health administration departments should pay more attention to the rational allocation of health resources. Furthermore, they should increase financial support and manpower in village-level health institutions.

[Interaction Between Occupational Vanadium Exposure and hsp70-hom on Neurobehavioral Function].

OBJECTIVE: In determine the effect of heat shock protein 70-hom gene (hsp70-hom) polymorphism on the neurobehavioral function of workers exposed to vanadium. METHODS: Workers from the vanadium products and chemical industry were recruited by cluster sampling. Demographic data and exposure information were collected using a questionnaire. Neurobehavioral function was assessed by Neurobehavioral Core Test Battery. The hsp70-hom genotype was detected by restricted fragment length polymorphism-polymerase chain reaction (RFLP-PCR). A neurobehavioral index (NBI) was formulated through principal component analysis. RESULTS: Workers with a T/C genotype had worse performance in average reaction time, visual retention, digital span (backward), Santa Ana aiming (non-habitual hand), pursuit aiming (right points, total points), digit symbol and NBI score than others (P < 0.05). The relative risk of abnormal NBI score of the workers with a T/C genotype was 1.748 fold of those with a T/T genotype. The relative risk of abnormal.NBI score of the workers exposed to vanadium was 3.048 fold of controls (P < 0.05). But after adjustment with age and education, only vanadium exposure appeared with a significant effect on NBI score. When gene polymorphism and vanadium exposure coexisted, the effect of vanadium on neurobehavioral function was attenuated, but the influence of T/C genotype increased Codds ratio (OR = 4.577, P < 0.05). After adjustment with age and education, the OR of T/C genotype further increased to 7.777 (P < 0.05). Vanadium exposure and T/C genotype had.a bio-interaction effect on NBI score Crelative excess risk due to interaction (RERI) = 4.12, attributable proportion (AP) = 0.7, synergy index (S) = 6.45]. After adjustment with age and education, the RERI became 2.49 and the AP became 0.75, but no coefficient of interaction was produced. CONCLUSION: Priorities of occupational protection should be given to vanadium-exposed workers with a hsp70-hom T/C genotype and low education level.

[Oxidative Stress Level of Vanadium-exposed Workers].

OBJECTIVE: To determine the oxidative stress level in peripheral blood of vanadium-exposed workers, as an indication of population health effect of vanadium on human neurobehavioral system. METHODS: 86 vanadium-exposed workers and 65 non-exposed workers were recruited by cluster sampling. A questionnaire was administered to collect demographic and occupational exposure information. Serum activity of superoxide dismutase (SOD), inducible nitric oxide synthase (iNOS) and malonaldehyde (MDA) contents were detected by kit assay. The differences in oxidative stress level between vanadium-exposed and non-exposed workers were compared. RESULTS: Vanadium-exposed workers had higher levels of MDA contents than the controls. The total superoxide dismutase(T-SOD) activity in vanadium-exposed workers was significantly lower than that in the controls, which was associated with lowered levels of manganese superoxide dismutase (Mn-SOD) activity. No changes in serum levels of cupro-zinc superoxide dismutase (CuZn-SOD) was found in vanadium-exposed workers. No difference in iNOS activity was found between vanadium-exposed workers and controls. CONCLUSION: Vanadium exposure increases free radical production in serum and reduces antioxidant capacity. But the relationship between vanadium exposure and iNOS damage remains uncertain.

[The dose-response relationship of chrysotile asbestos exposure and lung cancer in cohort study].

OBJECTIVE: To clarify the dose-response relationship between asbestos dust exposure and lung cancer incidence in chrysotile asbestos miners by fixed cohort study and to investigate the incidence rates of lung cancer in exposure to different concentrations of asbestos dust. METHODS: A retrospective cohort study was conducted in 1932 asbestos miners who registered from January 1, 1981 to December 31, 1988, had worked for at least 1 year, and had no obvious cardiopulmonary diseases; the cohort study began in July 2009 and covered a time span of 29 years (1981 - 2009). The personal information, occupational history, disease history, and health data of these miners were recorded, and the monitoring data on dust concentrations in the mine over the years were collected. The dose-response relationship between asbestos dust concentration and lung cancer incidence was established by the method of life table; a regression equation was fitted to predict the excess incidence rates of lung cancer under the conditions of different working years and dust concentrations. RESULTS: A significant dose-response relationship was observed between cumulative exposure (Ce) and cumulative probability (Px) of lung cancer incidence, and the smokers hada higher Px than nonsmokers. When Ce was less than 2000 mg/m(3)·each year, Px reached 6.58/10000; when Ce was not less than 2000 mg/m(3)·and less than 3000 mg/m(3)·each year, Px reached 91.72/10000; when Ce was more than 5000 mg/m(3)·each year, Px was as high as 141.02/10000. The three models were fitted to obtain the optimal regression equation: Px = -0.0004Ce(2) + 0.0052Ce - 0.0011 (r(2) = 0.9387). In the workshop of asbestos mine in this study, the average dust concentration was 85 times higher than the limit in 2009, so the excess incidence rate of lung cancer was 112.598/10000 if the miners worked under this condition for 40 years, according to the equation. CONCLUSION: There is a significant dose-response relationship between cumulative asbestos exposure and lung cancer incidence in chrysotile asbestos miners. The risk for lung cancer rises as asbestos exposure increases.

[Development of a quality of working life scale (QWL7-32)].

OBJECTIVE: To develop a simple structured scale measuring quality of working life (QWL) from the perspective of occupational health and safety. METHODS: We identified the dimensions and items of QWL through literature review, brainstorming and expert panel discussions, and developed a pre-test questionnaire. The pre-test questionnaire was tested in school teachers and revised accordingly. The QWL Scale was eventually validated in 516 The school teachers in Chengdu. We examined the validity and reliability of the final scale (QWL7-32). RESULTS: exploratory factor analysis extracted seven factors with an eigenvalue greater than 1. Those seven factors contributed to 60.1% of the total variance. The confirmatory factor Analysis endorsed the seven factor model. The seven-dimension scale had good convergent validity and discriminant validity. The Cronbach's alpha coefficients of the QWL7-32 scale and all its seven dimensions were around or higher than 0.70 (P < 0.01). The test-retest correlation coefficients of the scale and all its seven dimensions were close to or greater than 0.60 (P < 0.01). CONCLUSION: The QWL7-32 scale has acceptable validity and reliability. It measures QWL in a comprehensive, specific and accurate way, and can be used as an instrument for assessing QWL.

[Characteristics and stability of surveillance data on respiratory syndrome, during the Shanghai World Expo in Pudong New District].

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 related 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.

[Effect of magnitude and duration on the performance of Cumulative Sum].

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.

Epidemic features affecting the performance of outbreak detection algorithms.

BACKGROUND: Outbreak detection algorithms play an important role in effective automated surveillance. Although many algorithms have been designed to improve the performance of outbreak detection, few published studies have examined how epidemic features of infectious disease impact on the detection performance of algorithms. This study compared the performance of three outbreak detection algorithms stratified by epidemic features of infectious disease and examined the relationship between epidemic features and performance of outbreak detection algorithms. METHODS: Exponentially weighted moving average (EWMA), cumulative sum (CUSUM) and moving percentile method (MPM) algorithms were applied. We inserted simulated outbreaks into notifiable infectious disease data in China Infectious Disease Automated-alert and Response System (CIDARS), and compared the performance of the three algorithms with optimized parameters at a fixed false alarm rate of 5% classified by epidemic features of infectious disease. Multiple linear regression was adopted to analyse the relationship of the algorithms' sensitivity and timeliness with the epidemic features of infectious diseases. RESULTS: The MPM had better detection performance than EWMA and CUSUM through all simulated outbreaks, with or without stratification by epidemic features (incubation period, baseline counts and outbreak magnitude). The epidemic features were associated with both sensitivity and timeliness. Compared with long incubation, short incubation had lower probability (ß* = -0.13, P < 0.001) but needed shorter time to detect outbreaks (ß* = -0.57, P < 0.001). Lower baseline counts were associated with higher probability (ß* = -0.20, P < 0.001) and longer time (ß* = 0.14, P < 0.001). The larger outbreak magnitude was correlated with higher probability (ß* = 0.55, P < 0.001) and shorter time (ß* = -0.23, P < 0.001). CONCLUSIONS: The results of this study suggest that the MPM is a prior algorithm for outbreak detection and differences of epidemic features in detection performance should be considered in automatic surveillance practice.

Chemical composition and antimicrobial activity of the essential oil of kumquat (Fortunella crassifolia Swingle) peel.

The aim of this study was to determine the main constituents of the essential oil isolated from Fortunella crassifolia Swingle peel by hydro-distillation, and to test the efficacy of the essential oil on antimicrobial activity. Twenty-five components, representing 92.36% of the total oil, were identified by GC-MS analysis. The essential oil showed potent antimicrobial activity against both Gram-negative (E. coli and S. typhimurium) and Gram-positive (S. aureus, B. cereus, B. subtilis, L. bulgaricus, and B. laterosporus) bacteria, together with a remarkable antifungal activity against C. albicans. In a food model of beef extract, the essential oil was observed to possess an effective capacity to control the total counts of viable bacteria. Furthermore, the essential oil showed strongly detrimental effects on the growth and morphological structure of the tested bacteria. It was suggested that the essential oil from Fortunella crassifolia Swingle peel might be used as a natural food preservative against bacteria or fungus in the food industry.

[Association of occupational stress with quality of working life].

OBJECTIVE: To assess occupational stress and quality of working life (QWL) and their association in workers with different jobs. METHODS: The Occupational Stress Inventory Revised Edition (OSI-R) and Quality of Working Life Scale (QWL7-32) were administered to 194 workers in the Liaohe Oilfield. The association between occupational stress and quality of working life was analysed by controlling job types and other confounding variables. RESULTS: Office workers had significantly lower scores in occupational role questionnaire (ORQ) and personal strain questionnaire (PSQ) and higher scores in personal resources questionnaire (PRQ) and QWL than physical laborers (P<0.05). The PSQ scores were positively correlated with the ORQ scores and negatively correlated with the PRQ scores. The QWL scores were negatively correlated with the ORQ and PSQ scores, and positively correlated with the PRQ scores (P<0.001). The QWL scores changed with job types. The QWL scores declined with the increase of stress levels (P<0.01). ORQ, role boundary (RB), role insufficiency (RI), physical environment (PE), PSQ, vocational strain (VS), interpersonal strain (IS) and PRQ had a significant impact on quality of working life (P<0.01). CONCLUSION: Occupational stress is associated with quality of working life. Quality of working life can be improved through control of occupational stress.

[The comparison of two different types of baseline data regarding the performance of aberration detection algorithm for infectious disease outbreaks].

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 C1, 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.

[Comparison on the performance of both temporal and temporal-spatial models for outbreak detection through China Infectious Diseases Automated-alert and Response System (CIDARS)].

OBJECTIVE: To analyze the pilot results of both temporal and temporal-spatial models in outbreaks detection in China Infectious Diseases Automated-alert and Response System (CIDARS) to further improve the system. METHODS: The amount of signal, sensitivity, false alarm rate and time to detection regarding these two models of CIDARS, were analyzed from December 6, 2009 to December 5, 2010 in 221 pilot counties of 20 provinces. RESULTS: The sensitivity of these two models was equal (both 98.15%). However, when comparing to the temporal model, the temporal-spatial model had a 59.86% reduction on the signals (15 702) while the false alarm rate of the temporal-spatial model (0.73%) was lower than the temporal model (1.79%), and the time to detection of the temporal-spatial model (0 day) was also 1 day shorter than the temporal model. CONCLUSION: Comparing to the temporal model, the temporal-spatial model of CIDARS seemed to be better performed on outbreak detection.

[Preliminary application on China Infectious Diseases Automated-alert and Response System (CIDARS), between 2008 and 2010].

OBJECTIVE: To analyze the results of application on China Infectious Diseases Automated-alert and Response System (CIDARS) and for further improving the system. METHODS: Amount of signal, proportion of signal responded, time to signal response, manner of signal verification and the outcome of each signal in CIDARS were descriptively analyzed from July 1, 2008 to June 30, 2010. RESULTS: A total of 533 829 signals were generated nationwide on 28 kinds of infectious diseases in the system. 97.13% of the signals had been responded and the median time to response was 1.1 hours. Among them, 2472 signals were generated by the fixed-value detection method which involved 9 kinds of diseases after the preliminary verification, field investigation and laboratory tests. 2202 signals were excluded, and finally 246 cholera cases, 15 plague cases and 9 H5N1 cases as well as 39 outbreaks of cholera were confirmed. 531 357 signals were generated by the other method - the 'moving percentile method' which involved 19 kinds of diseases. The average amount of signal per county per week was 1.65, with 6603 signals (1.24%) preliminarily verified as suspected outbreaks and 1594 outbreaks were finally confirmed by further field investigation. For diseases in CIDARS, the proportion of signals related to suspected outbreaks to all triggered signals showed a positive correlation with the proportion of cases related to outbreaks of all the reported cases (r = 0.963, P < 0.01). CONCLUSION: The signals of CIDARS were responded timely, and the signal could act as a clue for potential outbreaks, which helped enhancing the ability on outbreaks detection for local public health departments.

[Comparison on the different thresholds on the 'moving percentile method' for outbreak detection].

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 P(50), P(60), P(70), P(80) and P(90) 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 P(50). For non-cholera infectious diarrhea, dysentery, typhoid and paratyphoid, and epidemic mumps, it was P(60). As for hepatitis A, influenza and rubella, the threshold was P(70), but for epidemic encephalitis B it was P(80). For the following diseases 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 P(90). 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 (P(50)) 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.

[Study on mental workload of teachers in primary schools].

OBJECTIVE: To investigate the distribution characteristics and influencing factors of mental workload of teachers in primary schools. METHODS: National Aeronautics and Space Administration-Task Load Index (NASA-TLX) was used to assess the mental workload levels for 397 teachers of primary schools in a city. RESULTS: The mental workload (64.34+10.56) of female teachers was significantly higher than that (61.73+ 9.77) of male teachers (P<0.05). The mental workload (65.66+10.42) of "-35" years old group was the highest. When age of teachers was younger than 35 years old, there was a positive correlation between the mental workload and age (r=0.146, P<0.05). When age of teachers was older than 35 years old, there was a negative correlation between the mental workload and age (r=-0.190, P<0.05). The teachers with higher education level felt higher mental workload (unstandardized coefficients B=1.524, standardized coefficients /=0.111, P<0.05). There was a positive correlation between the mental workload and working hours per day (unstandardized coefficients B =4.659, standardized coefficients/3 =0.223, P<0.001). CONCLUSION: Mental workload of the teachers in primary schools is closely related to age, educational level and work hours per day. Work hours per day is an important risk factor for mental workload. Reducing work hours per day (8 hours) is an effective measure of alleviating the mental workload of teachers in primary schools.

[Application of cumulative sum control chart algorithm in the detection of infectious disease outbreaks].

In recent years, for improving the ability of early detection on infectious disease outbreak, many researchers study the disease outbreak detection algorithms, based on many disease surveillance data, expecting to detect the abnormal increasing and cluster of disease and symptom at an early stage by adopting appropriate algorithm. This paper introduces a cumulative sum control chart method, one of statistical process control algorithms widely used in foreign countries and describes its basic principle and characteristic, key points of design, typical examples in application of disease outbreak detection of cumulative sum method, with expect to provide reference for its application in studies of disease outbreak early warning in China.