Development and application syndromic surveillance and early warning system in border area in Yunnan Province / 中华流行病学杂志

Objective: To establish a dynamic syndromic surveillance system in the border areas of Yunnan Province based on information technology, evaluate its effectiveness and timeliness in the response to common communicable disease epidemics and improve the communicable disease prevention and control in border areas. Methods: Three border counties were selected for full coverage as study areas, and dynamic surveillance for 14 symptoms and 6 syndromes were conducted in medical institutions, the daily collection of information about students' school absence in primary schools and febrile illness in inbound people at border ports were conducted in these counties from January 2016 to February 2018 to establish an early warning system based on mobile phone and computer platform for a field experimental study. Results: With syndromes of rash, influenza-like illness and the numbers of primary school absence, the most common communicable disease events, such as hand foot and mouth disease, influenza and chickenpox, can be identified 1-5 days in advance by using EARS-3C and Kulldorff time-space scanning models with high sensitivity and specificity. The system is easy to use with strong security and feasibility. All the information and the warning alerts are released in the form of interactive charts and visual maps, which can facilitate the timely response. Conclusions: This system is highly effective and easy to operate in the detection of possible outbreaks of common communicable diseases in border areas in real time, so the timely and effective intervention can be conducted to reduce the risk of local and cross-border communicable disease outbreaks. It has practical application value.

Prenatal pyrethroid pesticides exposure and neurodevelopment of 2-year-old children: a birth cohort study / 中华预防医学杂志

Objective: To investigate the influence and critical windows of prenatal exposure to pyrethroid pesticides (PYRs) on neurodevelopment of 2-year-old children. Methods: The subjects of this study were derived from the Xuanwei Birth Cohort. A total of 482 pregnant women who participated in the rural district of Xuanwei birth cohort from January 2016 to December 2018 were included. Maternal urinary concentrations of PYRs metabolites during 8-12 gestational weeks, 20-23 gestational weeks and 32-35 gestational weeks were measured with ultra high performance liquid chromatography system coupled with a tandem mass spectrometry detector. Child neurodevelopment was evaluated with the Bayley Scales of Infant and Toddler Development-Third Edition at 2 years of age. Multivariate linear regression models and binary logistic regression models were used to assess the association between PYRs exposure during pregnancy and children's neurodevelopment. Results: A total of 360 mother-child pairs had complete data on maternal urinary PYRs metabolites detection and children's neurodevelopment assessment. The detection rate of any one PYRs metabolites during the first, second and third trimester were 93.6% (337/360), 90.8% (327/360) and 94.2% (339/360), respectively. The neurodevelopmental scores of Cognitive, Language, Motor, Social-Emotional, and Adaptive Behavior of 2-year-old children were (102.3±18.9), (100.2±16.3), (102.0±20.3), (107.8±23.3) and (85.8±18.6) points, respectively. After controlling for confounding factors, 4-fluoro-3-phenoxybenzoic acid (4F3PBA, one of PYRs metabolites) exposure in the first trimester reduced Motor (β=-5.02, 95%CI: -9.08, -0.97) and Adaptive Behavior (β=-4.12, 95%CI:-7.92, -0.32) scores of 2-year-old children, and increased risk of developmental delay of adaptive behavior (OR=2.07, 95%CI:1.13-3.82). Conclusion: PYRs exposure during the first trimester of pregnancy may affect neurodevelopment of 2-year-old children, and the first trimester may be the critical window.

Predictive study on school absences due to illness with seasonal exponential smoothing method / 中华疾病控制杂志

Objective To establish a suitable exponential smoothing prediction model for school absentees due to illness, to discuss its application value for predicting school absences due to illness, and to provide a basis for early warning of absence due to illness. Methods Numbers of schools absences by year and month due to illness in 30 primary schools from November 2015 to June 2017 were collected from symptom monitoring system of border county, southern Yunnan and Simple seasonal model, Winters addition model and Winters multiplication model were used to build simulation. The data of July 2017 to December 2017 were used for model validation. The three models were overall compared and evaluated through indicator analysis, statistical analysis and residual diagram analysis. The best model was selected to predict school absences due to illness from January 2018 to March 2018. Results Simple seasonal model, Winters addition model and Winters multiplication model were used to fit the variation trend of number of school absences due to illness in time series. The root mean square error (RMSE) of three models were 445.11, 420.99 and 258.75; R2adj were 0.72, 0.72 and 0.77; R2 were 0.92, 0.93 and 0.98; P values of Ljung-Box Q were 0.54, 0.43 and 0.21. As for prediction method linear trend, Alpha were 0.999, 1.000 and 0.298. The average relative error between predicted value and actual value was 9.62%, 21.90% and 7.52%. Conclusion Winters multiplication model has practical value to predict school absence due to illness and provide scientific basis for early identification of abnormal signals.

The association between body mass index and non-alcoholic fatty liver disease / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the association of body mass index (BMI) with alcoholic fatty liver disease (NAFLD).</p><p><b>METHODS</b>A cohort of 725 adult subjects underwent general health check-up at our hospital in July 2008, then were followed up in 2011. The clinical data including body mass index(BMI), blood pressure, lab testing results and liver ultrasonic findings were retrospectively analyzed. The NAFLD was diagnosed according to the guidelines for management of nonalcoholic fatty liver disease: an updated and revised edition in 2010 based on liver ultrasound results. The risk factors for NAFLD were analyzed with multivariate logistic regression.</p><p><b>RESULTS</b>One hundred and sixty two NAFLD cases and 563 non-NAFLD cases were found in 2008 check-up. Among 563 non-NAFLD subjects, NAFLD was developed in 132 (23.4%) at follow-up in 2011. The incidence of NAFLD was correlated with the baseline BMI (χ²=82.861，P<0.01). Multivariate logistic regression analysis showed that baseline BMI，systolic blood pressure, alanine aminotransferase and the increase of BMI were the independent risk factors, while high density lipoprotein-cholesterol (HDL-C) was the protective factor for the development of NAFLD. Among 162 NAFLD cases, 71 (43.8%) had no evidence of NAFLD at the second check-up in 2011. The remission of NAFLD was negatively correlated with baseline BMI (χ²=22.425，P<0.01). Multivariate logistic regression analysis showed that male sex, baseline BMI and the increase of BMI were negatively associated with remission of NAFLD, while the age was positively associated with the remission of NAFLD.</p><p><b>CONCLUSION</b>The development and remission of NAFLD are frequently encountered in health check-up subjects, which are closely related to baseline BMI and changes of BMI during the follow-up．</p>