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Cryopyrin-associated periodic syndrome (CAPS) comprises a group of disorders characterized by recurrent bouts of systemic inflammation related to overactivation of inflammasome. So far, neither large cases of the correlation between genotype and phenotype nor treatment strategies have been clearly stated in China. Here, we studied the clinical and genetic characteristics and their correlation from 30 CAPS patients in China. We identified the pathogenesis for novel mutations by activating NLRP3 inflammasome for peripheral cells with ATP plus LPS, compared characteristics with other case series, and analyzed treatment outcomes of these patients. The patients harbored 19 substitutions in NLRP3, and 8 of them were novel mutations. Among these novel mutations, percentages of severe musculoskeletal, ophthalmologic, and neurological symptoms were higher compared with other case serials. The correlation of phenotypes and their variants seemed different in our cases, such as T350M, S333G/I/R, and F311V (somatic mosaicism). Ten patients received Canakinumab treatment, which proved effective at alleviating musculoskeletal, neurological, auditory, visual manifestations, fever, and rash for 10-20 months follow-up. Patients treated with prednisolone or prednisolone plus thalidomide or methotrexate, tocilizumab, TNF inhibiting agents, and sirolimus achieved only partial remission. Importantly, we firstly identified somatic mosaicism mutation of F311V, which was severe. Our study extended the spectrum of genotype and phenotype and characteristics of their correlations and provided detailed responses to different treatment strategies. These data provide guidance for future diagnosis and management for CAPS. [ABSTRACT FROM AUTHOR]

Land surface temperature (LST) is a key variable within the Earth's climate system and a necessary input parameter required by numerous land-atmosphere models. It can be directly retrieved from satellite thermal infrared (TIR) observations, but cloud contamination results in many spatial missing. To investigate the temporal and spatial variations of LST in China, long-term, high-quality, and spatio-temporally continuous LST datasets (i.e., all-weather LST) are urgently needed. Fusing satellite TIR LST and reanalysis datasets is a viable route to obtain long time-series all-weather LST. Among satellite TIR LSTs, the MODIS LST is the most commonly used and a few all-weather LST products generated in this way have been reported recently. However, the publicly reported all-weather LSTs are not available during the temporal gaps of MODIS between 2000 and 2002. In this context, we report a daily 1-km all-weather LST dataset for the Chinese landmass and surrounding areas -- TRIMS LST. Different from other products, the TRIMS LST begins on the first day of the new millennium i.e., January 1, 2000). The TRIMS LST was generated based on the Enhanced Reanalysis and Thermal infrared remote sensing Merging (E-RTM) method. Specifically, the original RTM method was used to generate the TRIMS LST outside the temporal gaps. Two newly developed approaches, including the Random-Forest based Spatio-Temporal Merging (RFSTM) approach and Time-Sequential LST based Reconstruction (TSETR) approach, were used to produce Terra/MODIS-based and Aqua/MODIS-based TRIMS LSTs during the temporal gaps, respectively. Thorough evaluation of the TRIMS LST was conducted. A comparison with the GLDAS and ERA5-Land LSTs demonstrates that TRIMS LST has similar spatial patterns but higher image quality, more spatial details, and no evident spatial discontinuities. Further comparison with MODIS and AATSR LSTs shows that TRIMS LSTs agree well with them, with mean bias deviation (MBD) between -0.40 K and 0.30 K and standard deviation of bias (STD) between 1.17 K and 1.50 K. Validation based on ground measured LST at 19 ground sites showed that the mean bias error (MBE) of the TRIMS LST ranged from -2.26 K to 1.73 K and the root mean square error RMSE) was 0.80 K to 3.68 K, with no significant difference between the clear-sky and cloudy conditions. The TRIMS LST has already been used by scientific communities in various applications such as soil moisture downscaling, evapotranspiration estimation, and urban heat island (UHI) modelling. [ABSTRACT FROM AUTHOR]

OBJECTIVES: This study investigated the effectiveness and identified the cutoff values of the computer-based Farnsworth-Munsell 100- Hue (CFM-100) test for screening color vision deficiencies in the pre-employment examination of civil aviators in China. METHODS: Firstly, subjects were stratified into normal, color weakness, and color blindness with the Ishihara pseudoisochromatic plate test (IPPT) by two ophthalmologists. Then they randomly completed CFM-100 and Farnsworth-Munsell 100-Hue (FM-100) tests. Total error scores (TES) and the time taken for the CFM-100 and FM-100 were analyzed and the cutoff values for the CFM-100 were determined. RESULTS: Of 218 subjects, 159 were normal while 59 were diagnosed with dyschromatopsia. The TES of the CFM-100 were congruent with those of the FM-100 (20.0 ± 18.8 vs. 20.6 ± 17.7, 160.9 ± 66.0 vs. 151.1 ± 66.4). The testing time for the CFM-100, however, was less than the FM-100 (10.3 ± 2.8 min vs. 12.9 ± 2.9 min, 7.8 ± 2.5 min vs. 12.6 ± 3.3 min). The correlation coefficient R was 0.93 and Cohen’s kappa was 0.89 for the two methods. Further analyses defined 34 as the cutoff value to differentiate excellent from fair color discrimination (sensitivity 58.0%, specificity 94.7%) and 101 as the cutoff value to judge fair vs. poor (sensitivity and specificity both 98.8%) for the CFM-100. The cut-off value was 72 for distinguishing normal from defective color vision (sensitivity 96.6%, specificity 98.7%) and 110 was for distinguishing color weakness from color blindness (sensitivity 97.6%, specificity 97.7%) for the CFM-100. CONCLUSIONS: The CFM-100 is an effective method for the diagnosis of dyschromatopsia with high sensitivity in screening airline pilots. [ABSTRACT FROM AUTHOR]

The root-associated actinobacteria play important roles in plant growth, nutrient use, and disease resistance due to their functional diversity. Salvia miltiorrhiza is a critical medicinal plant in China. The root actinobacterial community structure has been studied; however, the functions of root-associated actinobacteria of S. miltiorrhiza have not been elucidated. This study aimed to decipher the diversity and function of the culturable root-associated actinobacteria in plant growth using culture-dependent technology and culturable microbe metagenomes. We isolated 369 strains from the root-associated actinobacteria, belonging to four genera, among which Streptomyces was dominant. Besides, the functional prediction revealed some pathways related to plant growth, nitrogen and phosphorus metabolism, and antagonistic pathogens. We systematically described the diversity and functions of the culturable root- associated actinobacteria community. Our results demonstrated that the culturable root-associated actinobacteria of S. miltiorrhiza have rich functionalities, explaining the possible contribution of culturable root-associated actinobacteria to S. miltiorrhiza’s growth and development. This study provides new insights into understanding the function of the culturable root-associated actinobacteria and can be used as a knowledge base for plant growth promoters and biological control agent development in agriculture. [ABSTRACT FROM AUTHOR]

Objective: This study aims to evaluate the prevalence of inappropriate hospital stays in a tertiary hospital in Shanghai, identify the causes for the inappropriateness and analyze the predictors.Design: A retrospective review of medical records.Setting: The cardiology and the orthopedics departments of a tertiary hospital in Shanghai, China.Participants: About 806 patients discharged from the cardiology or the orthopedics department of a tertiary hospital from March 2013 to February 2014.Interventions: Two reviewers audited 8396 hospital days of the cardiology department (n = 3606) and the orthopedics department (n = 4790) by adopting the Chinese Version of the Appropriateness Evaluation Protocol. Univariate and multivariate analysis were adopted to identify the predictors of higher levels of inappropriateness produced by internal causes.Main Outcome Measure: The prevalence of inappropriate hospital days.Results: It was found that 910 (25.2%) and 1940 (40.5%) hospital days were judged to be inappropriate in the cardiology and the orthopedics departments, respectively; and 753 (20.9%) and 1585 (33.1%) of these inappropriate hospital days were due to internal reasons, respectively. Awaiting tests, surgery or discharge were determined to constitute the main causes of inappropriateness for both departments. The predictors of higher levels of inappropriateness in the cardiology department were younger age, self-pay, outpatient admission and inappropriate admission. Self-pay, surgical and/or first-time admission patients exhibited the highest levels of inappropriateness in the orthopedics department.Conclusions: The rates of inappropriateness in the involved departments were relatively high. Further interventions should be designed and implemented, accordingly. [ABSTRACT FROM AUTHOR]

BACKGROUND: China's soil pollution poses serious health risks. However, data regarding the soil ingestion rate (SIR) of the Chinese population, which is critical to assessing associated health risks, are lacking. OBJECTIVES: We estimated soil ingestion of 177 Chinese children from Guangdong, Hubei, and Gansu Provinces. METHODS: We conducted this investigation by employing a tracer mass-balance method. We collected a duplicate of all food consumed and all feces and urine excreted on 1 d (n =153) and over 3 consecutive d (n = 24), as well as soil samples from play areas and drinking-water samples. We analyzed concentrations of the tracer elements Al, Ba, Ce, Mn, Sc, Ti, V, and Y in these samples using ICP-AES and ICP-MS and estimated the SIR for each subject. RESULTS: The estimated SIR data based on each tracer element were characterized by a skewed distribution, as well as higher inter-tracer and intersubject variation, with several outliers. After removing the outliers, daily SIR median (range) values in milligrams per day were Al, 27.8 (-42:0 to 257:3); Ba, 36.5 (-230.3 to 412.7); Ce, 35.3 (-21.2 to 225.8); Mn, 146.6 (-1259.4 to 1827.7); Sc, 54.8 (-4.5 to 292.0); Ti, 36.7 (-233.7 to 687.0); V, 92.1 (10.4 to 308.0); and Y, 59.1 (-18.4 to 283.0). Daily SIR median/95th percentile (range) values based on the best tracer method (BTM) were 51.7=216.6 (-9.5 to 297.6) mg=d. CONCLUSIONS: Based on the BTM, recommended SIR values for the general population of Chinese children (2:5 to 12 years old) are 52 mg=d for the central tendency and 217 mg=d for the upper percentile. We did not differentiate between outside soil and indoor dust. Considering the lower concentration of tracer elements in indoor dust than outside soil, actual soil and dust ingestion rates could be higher. [ABSTRACT FROM AUTHOR]

Gravity changes sometimes appear before a big earthquake. To determine the possible sources is important for recognizing the mechanism and further geodynamic studies. During the first two hours on March 11 before the Mw 9.0 Tohoku-Oki earthquake, the non-tidal gravity time series of superconducting gravimeters worldwide showed low-frequency (< 0.10 Hz) fluctuations with amplitude of ~1 to 4 x 10-8 ms-2 lasting ~10 - 20 minutes. Through comparing global seismicity with the arrival times of seismic waves, we find that the fluctuations were induced by the Mw 5.7 earthquake that occurred at 0:14:54.68 at (53.27°S, 118.18°W) along the eastern South Pacific Rise. Several body waves such as P, S are clearly recorded in the station with ~400 km distance to the hypocenter. The fluctuations are in response to the waves that propagate with a velocity of about 4 km s-1. Their amplitudes are proportional to the inverse of the epicentral distances even though the fluctuations of European sites were overlapped with waves associated with a smaller, i.e., Mw 2.6, event in Europe during this period. That is, the Mw 5.7 earthquake induced remarkable gravity fluctuations over long distances at stations all over the world. As such, the foreshocks with larger magnitudes occurred before the Mw 9.0 earthquake would have more significant influence on the gravity recordings and the seismic-wave induced component should be removed during the analysis of anomalies prior to a great earthquake in future studies. [ABSTRACT FROM AUTHOR]

Brominated flame retardants (BFRs) such as polybrominated diphenyl ethers (PBDEs) are important pollutants, yet few data on ambient BFRs levels have been available for North China, one of the most developed regions of the country. In this study, we investigated levels and spatial distributions of BFRs based on gridded field observations coupled with passive air sampling in the aforementioned region. A model incorporating both point and nonpoint sources was developed to simulate the spatial distribution and to achieve source apportionment. Although high concentration was observed at an electronic-waste (e-waste) recycling site, the median level of the sum of tri-, tetra-, hepta-, hexa-, and hepta-PBDEs (Σ10PBDEs) was 0.56 ng/sample, which was lower than those observed previously in mainland China. Source apportionment revealed that nonpoint emissions contributed nearly 78% of Σ10PBDEs observed in this study. In contrast, high levels of BDE-209 and DBDPE were observed, with median concentrations of 4.0 and 10.2 ng/sample, respectively. Point sources located in the region around Laizhou Bay, Shandong Province were the major sources, which contributed 31% of BDE-209 and 70% of DBDPE observed in this study, indicating that this manufacturing base was the most important source region for atmospheric deca-BFRs in North China. To our knowledge, this is the first study to report source apportionment of atmospheric BFRs based on gridded field observations. [ABSTRACT FROM AUTHOR]

Background: Health care system reform is a major issue in many countries and therefore how to evaluate the effects of changes is incredibly important. This study measured residents' satisfaction with community health care service in Shanghai, China, and aimed to evaluate the effect of recent health care system reform. Methods: Face-to-face interviews were performed with a stratified random sample of 2212 residents of the Shanghai residents using structured questionnaires. In addition, 972 valid responses were retrieved from internet contact. Controlling for sex, age, income and education, the study used logistic regression modeling to analyze factors associated with satisfaction and to explain the factors that affect the residents' satisfaction. Results: Comparing current attitudes with those held at the initial implementation of the reform in this investigation, four dimensions of health care were analyzed: 1) the health insurance system; 2) essential drugs; 3) basic clinical services; and 4) public health services. Satisfaction across all dimensions improved since the reform was initiated, but differences of satisfaction level were found among most dimensions and groups. Residents currently expressed greater satisfaction with clinical service (average score=3.79, with 5 being most satisfied) and the public health/preventive services (average score=3.62); but less satisfied with the provision of essential drugs (average score=3.20) and health insurance schemes (average score=3.23). The disadvantaged groups (the elderly, the retired, those with only an elementary education, those with lower incomes) had overall poorer satisfaction levels on these four aspects of health care (P<0.01). 25.39% of the respondents thought that their financial burden had increased and 38.49% thought that drugs had become more expensive. Conclusion: The respondents showed more satisfaction with the clinical services (average score=3.79) and public health services/interventions (average score=3.79); and less satisfaction with the health insurance system (average score=3.23) and the essential drug system (average score=3.20). Disadvantaged groups showed lower satisfaction levels overall relative to non-disadvantaged groups. [ABSTRACT FROM AUTHOR]

Abstract: Based on EOS/MODIS remote sensing image data, with the CASA model to simulate the net primary productivity (NPP) of terrestrial vegetation in Qinghai Lake valley, calculate and invert spatial distribution of vegetation carbon storage of the Qinghai Lake Valley, the results showed that there were total 639.77×104t vegetation carbon storage in 2007 in Qinghai Lake Valley, the total carbon fixation value was 43.7×108 Yuan. Carbon storage showed obvious differences in vegetation types, among which the most alpine meadows are up to 437.37×104t, followed by warm steppe 93.70×104t, sparse vegetation on alpine flowstone slope 59.02×104t, alpine swamp 25.27×104t, vegetation carbon storage appears to be decreasing gradually with the elevation around the lake. [Copyright &y& Elsevier]

Load model is one of the most important elements in power system simulation and control. Based on more than 20 years of practice using load characteristic recorders in the measurement-based load modeling, this paper proposes the Expectation Composite Load Model to predict unseen data. The methods for load bus classification and parameter identification are also provided. The generalization capability of the proposed load modeling is validated by the measured load dynamics and system dynamics during two three-phase short circuit tests of the NE power grid in China. In order to evaluate the measurement-based load model, the Probabilistic Collocation Method (PCM) is applied to quantitatively analyze uncertainties of the simulation responses raised by the parameters. [ABSTRACT FROM AUTHOR]

No other country has undergone health care reforms as dramatic as China's. Starting in 1978, China reformed its health system from a governmental, centrally planned, and universal system to a heavily market-based one. Now, three decades later, the Chinese government openly acknowledges that the reforms failed and seeks new directions. This paper adds to the literature by examining China's health care from a system perspective, describing its health services delivery, access, outcomes, and population health in the post-reform era. It also identifies the main issues in the current system and highlights the key lessons learned from China's reform process. [ABSTRACT FROM AUTHOR]

A load model is one of the most important elements in power system simulation and control. Recently, the constant impedance, constant current, and constant power load in combination with the induction motor load have been widely used as the composite load model, whose parameters are all identified from the field measurements in measurement-based load modeling practices so far. However, there is virtually no research conducted on whether all these parameters could really be identified. This paper investigates the possibility on reducing the number of composite load model parameters to be identified from field measurements. This paper first shows that direct application of the IEEE load motor parameters in the composite load model may be inadequate on describing the load dynamics over different operating status. Then the perturbation method is used to derive the trajectory sensitivities of the equivalent motor parameters, based on which the reduction on the identified parameters of the composite load model is presented. Two cases of measurement-based load modeling in North China and Northeast China are studied to illustrate the validity of the reduction method. It is shown that the reduction does not lose the model's capability on describing the load dynamics. The reduction on the number of identified parameters not only provides a possible way to solve the multi-valued load model problem based on the current practices on measurement-based load modeling, but it also facilitates building of the load model with more components included in it. Meanwhile, reducing the identified parameters reduces the identification time; thus, the proposed strategy significantly enhances the efficiency of the load modeling work. [ABSTRACT FROM AUTHOR]

This paper applies SAR Interferometry for ground deformation in two cases: the 1998 Zhangbei-Shangyi Earthquake in Northern China and the urban subsidence in Suzhou City from 1993 to 2000. It is concluded that SAR interferometry may provide valuable information for understanding the spatial patterns and progress of natural hazards. SAR interferometry is also critical for mechanism studies and hazard mitigation. [ABSTRACT FROM AUTHOR]

The article discusses the appraisal of complex health-care reforms in China. It says that the country has launched a three-year reform plan worth 125 billion dollars in 2009 for a comprehensive universal health coverage by 2020. It cites that the government's systemic reform provided positive developments in health care including primary care, finance redistribution, and human resources. It adds that China must reform providers' incentive structures and implement a stronger regulatory system.

Objective: The purpose of this study was to analyze the electrocardiographic features of the people living in the area with high incidence of unexplained sudden deaths in Yunnan province., Method: The electrocardiograms of 338 residents from three villages (Dayao, Ninglang, Heqing) with high incidence of unexplained sudden deaths and one control village (Dali) were analyzed [averaged age was (33.4 +/- 11.7) years, 175 men and 163 women]., Results: The incidence of cardiac arrhythmias was similar low in all groups. The left ventricular hypertrophy was observed in 34.6% of residents from Dayao. QTc significantly prolonged in the residents from all 3 high incidence areas compare the control area of Dali [control (386.8 +/- 27.22) ms, Ninglang (428.92 +/- 25.71) ms, Heqing (440.67 +/- 28.03) ms, Dayao (417.7 +/- 24.00) ms, P < 0.05 vs. control]. Incidence of U wave was significantly higher in Heqing village than that in control village (P < 0.05). The QUc of these 3 villages was: (613.67 +/- 37.34) ms, (597.19 +/- 46.47) ms, (608.59 +/- 39.59) ms respectively, and also significantly longer than the control village of Dali (589.33 +/- 41.27) ms (P < 0.05). The typical pattern of U wave presents as enlarged U wave and apparent T-U complex. In the 7 residents who have the family history of unexplained sudden death, 6 residents have U wave, and 4 of them present typical U wave pattern., Conclusion: The significant ECG changes in villages with high incidence of unexplained sudden death in Yunnan province were prolonged QTc, enlarged U wave and apparent T-U complex and these ECG features suggested the repolarization abnormalities of the heart in these subjects.

Objectives: To study the pathologic feature of sudden cardiac death in Yunnan province and to investigate the role of myocarditis., Methods: During the period from 1991 to 2006, there were 29 cases of sudden cardiac death with autopsy performed. Fourteen of these cases were diagnosed to have myocarditis based on Dallas criteria and World Heart Federation's consensus. The clinical and pathologic findings were reviewed. The cardiac conduction system was examined in details by serial sectioning in 3 cases., Results: Fourteen cases suffered with myocarditis, which accounted for 48% of all cases of sudden cardiac death studied. The age of the deceased ranged from 8 to 68 years (mean = 30 years), with male-to-female ratio equaled to 9:5. Lymphocytic myocarditis and neutrophil myocarditis were the two major types, affecting 11 and 3 cases, respectively. The inflammatory infiltrates were often patchy rather than diffuse. The inflammatory foci were detected only in 8% to 42% (average = 20%) of the paraffin sections of the heart tissue. These lesions were usually located in the lateral wall of left ventricle and occasionally in interventricular septum and right ventricular wall. Myocardial injury was mild in most cases while patchy myocytolysis or coagulation necrosis was observed only in a few cases. Most of the lesions were relatively new and histologic evidence of myocardial repairing sometimes coexisted. Pericarditis and subacute endocarditis were also identified in 4 and 1 cases, respectively. Atrioventricular node was involved by myocarditis in 1 of the 3 cases examined for cardiac conduction system. Two cases showed gross evidence of cardiac dilatation (either left ventricle or biventricular). Respiratory tract and pulmonary infection was present in 5 cases., Conclusions: Myocarditis represents one of the major pathologic changes of sudden cardiac death occurring in Yunnan province. The inflammation is usually focal. Further studies are required for delineation of possible etiologies which may include virus, bacteria or exogenous toxin.

Objective: To investigate the pathological features and causes of sudden death clustered in family or village in Yunnan province so as to provide the morphological basis for exploring its etiology and medical intervention., Methods: Autopsy was performed on 29 cases of clustered in family or village in Yunnan province during the period 1991-2006, 16 males and 13 females, aged 32 (8-69), accounting for 10.2% of whole sudden unexpected deaths occurring in the same period. The heart, lung, liver, spleen, brain, kidney, intestinal tract, and other organs were examined macroscopically and histologically, including a study of cardiac conduction system in 5 cases. Pathological diagnosis of myocarditis was based on the Dallas Criteria and World Heart Federation's consensus while the histological evaluation of Keshan disease referred the China national guideline for pathological diagnosis of Keshan disease., Results: Based on the main pathological changes and the causes of death, these cases were classified into seven groups (group A-G). Group A comprised 11 cases (38%) with lymphocytic myocarditis accompanied with focal myocardial necrosis or degeneration. Group B comprised 3 cases (10%) with neutrophil myocarditis accompanied with focal myocytolysis or coagulation necrosis. Group C comprised 4 cases (14%) with arrhythmogenic right ventricle cardiomyopathy in which fatty infiltration of myocardium was the only pathological finding. Group D comprised 2 cases (7%) with ischemic heart disease in which fresh or old foci of myocardial infarction were found but coronary stenosis was shown only in one case. Group E comprised 2 cases (7%) with left ventricle hypertrophy and obstructive muscle bundle in the outflow of left ventricle. Group F comprised 2 cases (7%) with allergic bronchitis or chronic bronchitis and pulmonary emphysema. Group G comprised the remaining 5 cases (17%) without any pathological finding that could explain sudden death. No cases suffered with Keshan disease and dilated cardiomyopathy. Focal but not diffuse inflammatory infiltration was the prominent histological feature of myocarditis in Yunnan cases. Among the five cases with histological examination of cardiac conduction system, 2 cases were detected to suffer from acute hemorrhage in His bundle and its left branching site, and the atrioventricular node of 1 case was involved. Different pathological changes coexisted in 4 pairs of family members as a cluster of sudden deaths. 3 of 4 first deaths had focal myocarditis and the other one had chronic infection. But 3 secondary deaths had myocardial ischemia and the other one had arrhythmogenic right ventricle cardiomyopathy. Pulmonary edema, acute respiratory infection and congestive or ischemic liver necrosis were found in some cases simultaneously., Conclusion: The pathological changes of the cases of clustered sudden death in Yunnan province are various, such as myocarditis, myocardial dysplasia and the other lethal heart-lung disorders. No case of Keshan disease has been found. Arrhythmogenic right ventricle cardiomyopathy and other foundational heart diseases might act as a background. It is very hard to contribute only one etiological factor to the clustering of sudden death in Yunnan. It was most likely that multiple factors cluster and trigger an outbreak of death in a definite time and space.

Objective: To identify the epidemiological and clinical features of unexpected sudden cardiac deaths (SUD) in Yunnan., Methods: Choosing the old SUD cases from Xiangyun, Heqing, Nanjian and Dayao counties and using the standardized verbal autopsy Form, we interviewed the family members of the cases, witnesses and doctors as well as reviewing their medical files to get relative information., Results: We identified 116 SUDs in 21 villages from 1984 to 2004. The village-specific annually standardized incidence rates were ranged from 0.2/1000 to 8.9/1000 (median = 0.8/1000). 66% and 29% of the SUDs occurred in July and August respectively. The incidence rates of SUD were higher (1.6/1000, chi(2) = 16, P < 0.01) in 10 - 39 year-olds, and higher in females than in males (RR = 1.6, 95% CI: 1.1 - 2.3). Seventy percent of SUD occurred in families having clustering nature and 60% of the additional cases in the family were occurred within 24 hours (median = 20 hours) after the first SUD identified in the family. SUD occurred in 23 families followed the first affected family in a village during the same season. In these 23 families, 61% of the first SUD occurred within 8 days after the first SUD in the first affected family. 68% and 66% of the SUDs did not have any complaints or signs during the last 3 weeks or from 3 weeks to 2 days prior to the onset of the disease. 63% of the SUDs had cardiac symptoms within the last 2 days prior to the onset with major symptoms as dizziness, nausea, faintness, unconsciousness, weakness and palpitation. The median duration from acute onset to death was 2 hours., Conclusions: The extreme time-space clustering of SUD in families and in villages suggested that the risk factors occurred in specific time and location. Familial clustered SUD cases had common exposure pattern. Sudden onset of acute cardiac symptoms often followed by sudden death. Epidemiological study on new cases was necessary to identify risk factors and to develop hypothesis for causation. In July 2005, we instituted a special SUD surveillance system for all the affected counties together with 10 counties which had no reported cases.