Latent period and incubation period with associated factors of COVID-19 caused by Omicron variant / 中华预防医学杂志

Objective: To estimate the latent period and incubation period of Omicron variant infections and analyze associated factors. Methods: From January 1 to June 30, 2022, 467 infections and 335 symptomatic infections in five local Omicron variant outbreaks in China were selected as the study subjects. The latent period and incubation period were estimated by using log-normal distribution and gamma distribution models, and the associated factors were analyzed by using the accelerated failure time model (AFT). Results: The median (Q1, Q3) age of 467 Omicron infections including 253 males (54.18%) was 26 (20, 39) years old. There were 132 asymptomatic infections (28.27%) and 335 (71.73%) symptomatic infections. The mean latent period of 467 Omicron infections was 2.65 (95%CI: 2.53-2.78) days, and 98% of infections were positive for nucleic acid test within 6.37 (95%CI: 5.86-6.82) days after infection. The mean incubation period of 335 symptomatic infections was 3.40 (95%CI: 3.25-3.57) days, and 97% of them developed clinical symptoms within 6.80 (95%CI: 6.34-7.22) days after infection. The results of the AFT model analysis showed that compared with the group aged 18-49 years old, the latent period [exp(β)=1.36 (95%CI: 1.16-1.60), P<0.001] and incubation period [exp(β)=1.24 (95%CI: 1.07-1.45), P=0.006] of infections aged 0-17 years old were prolonged. The latent period [exp(β)=1.38 (95%CI: 1.17-1.63), P<0.001] and the incubation period [exp(β)=1.26 (95%CI: 1.06-1.48), P=0.007] of infections aged 50 years old and above were also prolonged. Conclusion: The latent period and incubation period of most Omicron infections are within 7 days, and age may be a influencing factor of the latent period and incubation period.

Performance of screening of contacts of COVID-19 cases in same flight / 中华流行病学杂志

Objective: To understand the performance of 2019-nCoV nucleic acid detection in screening of contacts of COVID-19 cases in same flights and provide evidence for the effective screening of persons at high risk for the infection in domestic flights. Methods: The information of passengers who took same domestic flights with COVID-19 cases in China from April 1, 2020 to April 30, 2022 were retrospectively collected,and χ2 test was used to analyze positive nucleic acid detection rates in the passengers in different times before the onsets of the index cases, in different seat rows and in epidemic periods of different 2019-nCoV variants. Results: During the study period, a total of 433 index cases were identified among 23 548 passengers in 370 flights. Subsequently, 72 positive cases of 2019-nCoV nucleic acid were detected in the passengers, in whom 57 were accompanying persons of the index cases. Further analysis of the another 15 passengers who tested positive for the nucleic acid showed that 86.67% of them had onsets or positive detections within 3 days after the diagnosis of the index cases, and the boarding times were all within 4 days before the onsets of the index cases. The positive detection rate in the passengers who seated in first three rows before and after the index cases was 0.15% (95%CI: 0.08%-0.27%), significantly higher than in the passengers in other rows (0.04%, 95%CI: 0.02%-0.10%, P=0.007),and there was no significant difference in the positive detection rate among the passengers in each of the 3 rows before and after the index cases (P=0.577). No significant differences were found in the positive detection rate in the passengers, except the accompanying persons, among the epidemics caused by different 2019-nCoV variants (P=0.565). During the Omicron epidemic period, all the positive detections in the passengers, except the accompanying persons, were within 3 days before the onset of the index cases. Conclusions: The screening test of 2019-nCoV nucleic acid can be conducted in the passengers took the same flights within 4 days before the onsets of the index cases on board. Passengers who seated within 3 rows from the index cases can considered as the close contacts at high risk for 2019-nCoV, for whom screening should be conducted first and special managements are needed. The passengers in other rows can be classified as general risk persons for screening and management.

Latent period and incubation period with associated factors of COVID-19 caused by Omicron variant / 中华预防医学杂志

Objective: To estimate the latent period and incubation period of Omicron variant infections and analyze associated factors. Methods: From January 1 to June 30, 2022, 467 infected persons and 335 confirmed cases in five local Omicron variant outbreaks in China were selected as the study subjects. The latent period and incubation period were estimated by using log-normal distribution and gamma distribution models, and the associated factors were analyzed by using the accelerated failure time model (AFT). Results: The median (Q1, Q3) age of 467 Omicron infections including 253 males (54.18%) was 26 (20, 39) years old. There were 132 asymptomatic infections (28.27%) and 335 (71.73%) symptomatic infections. The mean latent period of 467 Omicron infections was 2.65 (95%CI: 2.53-2.78) days, and 98% of infections were positive for nucleic acid detection within 6.37 (95%CI: 5.86-6.82) days after infection. The mean incubation period of 335 symptomatic infections was 3.40 (95%CI: 3.25-3.57) days, and 97% of them developed clinical symptoms within 6.80 (95%CI: 6.34-7.22) days after infection. The results of the AFT model analysis showed that compared with the group aged 18~49 years old, the latent period [exp(β)=1.36 (95%CI: 1.16-1.60), P<0.001] and incubation period [exp(β)=1.24 (95%CI: 1.07-1.45), P=0.006] of infections aged 0~17 year old were also prolonged. The latent period [exp(β)=1.38 (95%CI: 1.17-1.63), P<0.001] and the incubation period [exp(β)=1.26 (95%CI: 1.06-1.48), P=0.007] of infections aged 50 years old and above were also prolonged. Conclusion: The latent period and incubation period of most Omicron infections are within 7 days, and age may be the influencing factor of the latent period and incubation period.

Time distribution of positive nucleic acid detection in imported cases infected with SARS-CoV-2 in China / 中华流行病学杂志

Objective: To analyze the time distribution of the first positive nucleic acid detection in imported cases infected with SARS-CoV-2 reported nationwide in China and provide references for further improvement of the prevention and control of COVID-19 in international travelers. Methods: The data of imported cases infected with SARS-CoV-2 reported by provinces from 24 July 2020 and 23 July 2021 were collected for the analysis on the time distribution of the first positive nucleic acid detection after entering China. Results: A total of 7 199 imported cases infected with SARS-CoV-2 were reported in 28 provinces during 24 July 2020 to 23 July 2021. The median interval (Q1, Q3) from the entry to the first positive nucleic acid detection of SARS-CoV-2 was 1 (0, 5) day. The imported cases who had the first positive nucleic acid detections within 14 days and 14 days later after the entry accounted for 95.15% (6 850/7 199) and 4.85% (349/7 199) respectively. Among these cases, 3.65% (263/7 199), 0.88% (63/7 199) and 0.32% (23/7 199) had the first positive nucleic acid detections within 15-21 days, 22-28 days and 28 days later after the entry respectively. The proportion of asymptomatic infections were 47.24% (3 236/6 850) and 63.61% (222/349) among the cases who had the first positive nucleic acid detections within 14 days and 14 days later after the entry respectively. A total of 39.54% (138/349) of cases infected with SARS-CoV-2 with the first positive nucleic acid detections 14 days later after the entry had inter-provincial travel after the discharge of entry point isolation. Conclusions: About 5% of the imported cases infected with SARS-CoV-2 were first positive 14 days later after the entry. In order to effectively reduce the risk of domestic COVID-19 secondary outbreaks caused by imported cases, it is suggested to add a nucleic acid test on 8th -13th day after the entry.

Epidemiological characteristics of infectious diseases of group A, B and C among Chinese students' population / 北京大学学报(医学版)

OBJECTIVE@#To analyze the secular trend, ranking change, age- and regional- characteristics of leading infectious diseases among Chinese students population aged 6 to 22 years from 2008 to 2017.@*METHODS@#Data were drawn from the national surveillance from 2008 to 2017, and the participants were students aged from 6 to 22 years who were diagnosed with notifiable infectious diseases. A total of 40 infectious diseases were classified into three groups based on national notifiable infectious diseases classification of A, B and C. The morbidity and mortality rates from infectious diseases were calculated using the numbers of students published by the ministry of education as the denominator. The age- and province-specific infectious diseases with the highest incidence were selected as the leading infectious diseases for analysis.@*RESULTS@#From 2008 to 2017, the incidence rate, the number of cases and the number of deaths of infectious diseases among the boys aged 6-22 years in China were higher than that of the girls, and the overall trend was downward during the study period. The incidence rates in the boys and girls decreased from 2008 to 2015 with decrease of 43.4% and 40.1%, respectively. However, by 2017, the increase rate rebounded with the increases of 47.1% and 53.8%. The rebound trend was mainly caused by the increase of group C of infectious diseases. During the past decade, the top leading three diseases of groups A and B of infectious diseases were viral hepatitis, tuberculosis and dysentery in 2018, respectively, which changed to tuberculosis, scarlet fever and viral hepatitis in 2017. The top leading three infectious diseases in terms of mortality were rabies, tuberculosis, and human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) in 2008, which were transformed into HIV/AIDS, rabies, and tuberculosis in 2017. There was no significantly obvious change in the incidence and mortality order of group C of infectious diseases during the decade. In the analysis of age groups and regions, the leading infectious diseases in groups A and B transferred from viral hepatitis to scarlet fever and tuberculosis, while in group C, mumps and infectious diarrhoea almost always dominated the leading infectious diseases. But in recent years, influenza and hand-foot-and-mouth disease increased significantly in the eastern region.@*CONCLUSION@#During the past decade, China has got remarkable achievements in the prevention and control of children infectious disease. However, the change patterns and characteristics of notifiable infectious diseases among children and adolescents show the urgent need for prevention and control of respiratory tract infectious diseases, HIV/AIDS and other sexually transmitted diseases as well as new emerging infectious diseases in China in the future. This study provides important basis for policy making of Chinese national school-based infectious disease prevention and control mechanism.

Research progress on pharmacological activity of peptides from Buthus martensii / 中草药

Buthus martensii is a precious Chinese materia medica, which has been extensively studied due to its various pharmacological effects such as anti-microbial activity, anti-tumor activity, analgesic activity, etc. This paper reviews domestic and foreign researches about the pharmacological activities of peptides from B. martensii, which will provide references for the utilization of these active medicinal peptides in B. martensii.

Research progress on medicinal values of scorpion venom components / 中国中药杂志

For thousands of years, scorpions and their venoms have been applied in traditional medicine in China to treat a variety of difficult miscellaneous diseases. The venom is a complex mixture of bioactive molecules, such as peptides and proteins (e.g. neurotoxins). Among them, neurotoxins (named scorpion toxins) are the most important bioactive components. Up to now, more and more characterized venom components have been isolated from different scorpions, providing numerous candidate molecules for drug design and development. Many investigations have shown the potent effects of venom or its components against the nervous, immune, infection, cardiovascular and neoplastic diseases. Moreover, the scorpion toxins could be used as molecular backbone to develop new specific drugs based on their unique structures and functions. In this review, we focus on the medicinal values and the possible mechanisms of scorpion toxins with promising medicinal prospect against the relative diseases, providing the data basis for further development of relative drugs.

Correlation between genetic polymorphisms of -855 G/C and -1140 G/A in GRIN1 gene and paranoid schizophrenia / 法医学杂志

OBJECTIVE@#To investigate the single nucleotide polymorphisms (SNP) of -855 G/C and -1140 G/A in promoter regions of GRIN1 gene and find their genetic correlation to paranoid schizophrenia as well as their applicable values in forensic medicine.@*METHODS@#The genetic polymorphisms of -855 G/C and -1140 G/A at the 5' end of GRIN1 gene were detected by PCR restriction fragment length polymorphism and PAGE in 183 healthy unrelated individuals of northern Chinese Han population and 172 patients of paranoid schizophrenia, respectively. The chi2 test was used to identify Hardy-Weinberg equilibrium of the genotype distribution. The differences of genotypes and allelic frequency distributions were compared between the two groups.@*RESULTS@#Distributions of the genotypic frequencies satisfied Hardy-Weinberg equilibrium in both groups. The difference of genotypes was statistically significant between female patient group and female control group in -855 G/C distribution (P < 0.05). The differences of genotypes and allelic frequencies were statistically significant not only between the patient group and the control group but also between female patient group and female control group in -1140 G/A distribution (P < 0.05).@*CONCLUSION@#The SNP of -1140 G/A in promoter regions of GRIN1 gene might positively correlate to paranoid schizophrenia. The genetic factor of schizophrenia is involved in gender tendency. And it could be useful in forensic identification of schizophrenia.

Application of the China Infectious Diseases Automated-alert and Response System in Guangxi, 2009-2011 / 中华流行病学杂志

<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>

Characteristics and stability of surveillance data on respiratory syndrome, during the Shanghai World Expo in Pudong New District / 中华流行病学杂志

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.

Effect of magnitude and duration on the performance of Cumulative Sum / 中华流行病学杂志

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.

Preliminary application on China Infectious Diseases Automated-alert and Response System (CIDARS), between 2008 and 2010 / 中华流行病学杂志

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 1,2008to 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 9H5N1 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 performance of both temporal and temporal-spatial models for outbreak detection through China Infectious Diseases Automated-alert and Response System(CIDARS) / 中华流行病学杂志

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.

Evaluation on the performance of China Infectious Disease Automated-alert and Response System(CIDARS)in Zhejiang province / 中华流行病学杂志

Objective To evaluate the performance of China Infectious Disease Automatedalert and Response System(CIDARS). Methods A retrospective analysis was conducted on data related to the warning signals, the outcome of signal verification, the field investigation of CIDARS,and the emergent events reported through Public Health Emergency Events Surveillance System from July 1,2008 to June 30, 2010 in Zhejiang province. The performance of CIDARS was qualitatively evaluated by indicators on its sensitivity and rote of false alarm. Results In total, 26 446 signals were generated by the system which involving 17 diseases, with an average of 2.83 signals per country per week. Among all the signals, 99.95% of them were responded. 0.90% of the signals were judged as suspected events via the preliminary verification, and 30 outbreaks were finally confirmed by field investigation. The sensitivity of the system was 69.77% with the false alarm rate as 1.39%. Conclusion The system seemed to have worked on the outbreak early warning of infectious diseases and could directly reflect the anomaly event emerged from the infectious disease reporting system.However, more efforts should be paid to the following areas as how to decrease the false positive signals, select suitable thresholds and increase the quality of data in order to enhance the accuracy of the system.

The effectiveness of China Infectious Disease Automated-alert and Response System(CIDARS)in the local regions / 中华流行病学杂志

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.

Comparison on the different thresholds on the 'moving percentile method' for outbreak detection / 中华流行病学杂志

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.

The comparison of two different types of baseline data regarding the performance of aberration detection algorithm for infectious disease outbreaks / 中华流行病学杂志

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.

Application of cumulative sum control chart algorithm in the detection of infectious disease outbreaks / 中华流行病学杂志

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.

Polymorphic distribution of FUT2/01 in northern Han Chinese population / 法医学杂志

OBJECTIVE@#To investigate the sequence features of FUT2/01 locus and its polymorphic distribution in Chinese population, and to discuss its application potential in forensic medicine.@*METHODS@#The alleles on FUT2/01 locus were amplified by PCR and then were sequenced. Furthermore, polymorphic distribution of the locus was analyzed by polyacrylamide gel electrophoresis. The genotypes were characterized with fluorescence labeling followed by automatic detection system.@*RESULTS@#The sequencing results only showed the length differences which were determined by the tandem repeats variance of the core sequence. There were 9 alleles and 28 genotypes identified from 162 individuals. The discrimination power and excluding probability of paternity were 0.9639 and 0.6266, respectively. In addition, the locus could be genotyped by automatic analysis very well.@*CONCLUSION@#The FUT2/01 locus exhibits high heterozygosity and individual identification power in Chinese Han population, and may be a valuable STR system for application in forensic medicine.