Systematic review on the characteristics of acute gastroenteritis outbreaks caused by sapovirus / 中华流行病学杂志

Objective: To understand the epidemiological and etiological characteristics of outbreaks on acute gastroenteritis caused by sapovirus (SaV) worldwide. Methods: Literature about the outbreaks on acute gastroenteritis caused by SaV were retrieved from the databases including WanFang, CNKI, PubMed and Web of Science after evaluation. Time, geography, setting and population distributions of outbreaks, transmission mode, SaV genotype and clinical characteristics of the patients were analyzed. Results: A total of 34 papers about SaV were included, involving 146 outbreaks occurred between October 1976 and April 2016. In these papers, 138 outbreaks were reported on the related months. All these outbreaks occurred in northern hemisphere. SaV outbreaks occurred all year around, but mainly in cold season, the incidence was highest in December (25 outbreaks) and lowest in in August (2 outbreaks). Most outbreaks were reported by Japan, followed by Canada, the United States of America and the Netherlands. There were 141 outbreaks for which the occurring settings were reported, child-care settings were most commonly reported setting (48/141, 34.04%), followed by long-term care facility (41/141, 29.08%) and hospital (16/141, 11.35%). Clinical symptoms of 1 704 cases in 31 outbreaks were reported, with the most common symptom was diarrhea (1 331/1 704, 78.12%), followed by nausea (829/1 198, 69.20%), abdominal pain (840/1 328, 63.25%), vomiting (824/1 704, 48.36%) and fever (529/1 531, 34.53%). Genotypes of SaV were determined for 119 outbreaks. GⅠ(51/119, 42.86%) and GⅣ (45/119, 37.82%) were predominant. The outbreaks of GⅣ SaV increased suddenly in 2007, and the outbreaks of GⅠ SaV mainly occurred in 2008 and during 2011-2013. Conclusions: SaV outbreaks were reported mainly by developed countries, with most outbreaks occurred in cold season, in child-care settings and long term care facility. GⅠ and GⅣ were the most common genotypes of SaV. Prevention and control of SaV outbreak in China seemed relatively weak, and it is necessary to conduct related training and to strengthen the SaV outbreak surveillance in areas where service is in need.

Association between obesity and DNA methylation among the 7-16 year-old twins / 中华流行病学杂志

Objective: On whole-genome scale, we tried to explore the correlation between obesity-related traits and DNA methylation sites, based on discordant monozygotic twin pairs. Methods: A total of 90 pairs of 6-17 year-old twins were recruited in Chaoyang district, Yanqing district and Fangshan district in Beijing in 2016. Information on twins was gathered through a self-designed questionnaire and results: from physical examination, including height, weight and waist circumference of the subjects under study. DNA methylation detection was chosen on the Illumina Human Methylation EPIC BeadChip. R 3.3.1 language was used to read the DNA methylation signal under quality control on samples and probes. Ebayes function of empirical Bayes paired moderated t-test was used to identify the differential methylated CpG sites (DMCs). VarFit function of empirical Bayes paired moderated Levene test was used to identify the differentially variables CpG sits (DVCs) in obese and normal groups. Results According to the obesity discordance criteria, we collected 23 pairs of twins (age range 7 to 16 years), including 12 male pairs. A total of 817 471 qualified CpG loci were included in the genome-wide correlation analysis. According to the significance level of FDR set as <0.05, no positive sites would meet this standard. When DMC CpG site cg05684382, with the smallest P value (1.26E-06) as on chromosome 12, the DVC CpG site cg26188191 with the smallest P value (6.44E-06) appeared in CMIP gene on chromosome 16. Conclusions: In this study, we analyzed the genome-wide DNA methylation and its correlation with obesity traits. After multiple testing corrections, no positive sites were found to have associated with obesity. However, results from the correlation analysis demonstrated sites cg05684382 (chr: 12) and cg26188191 (chr: 16) might have played a role in the development of obesity. This study provides a methodologic reference for the studies on discordance twins related problems.

Series study on the relationship between air quality index and tuberculosis incidence in Beijing / 中华流行病学杂志

Objective: To analyze the effect of air quality index (AQI) on the incidence of tuberculosis (TB) in Beijing, and to provide evidence for setting up a better program regarding prevention and control of tuberculosis. Methods: Generalized additive model (GAM) was used to analyze the association between AQI and the incidence of tuberculosis in Beijing, from January 1, 2014 to November 9, 2016. Confounding factors as meteorological conditions and time trends were under control. Results: In Beijing, a total of 14 533 TB cases with definite dates of onset were collected during the study period, with 36 children excluded from the study. Finally, 14 497 cases were included in the study, including 9 513 men and 4 984 women, with 11 290 adults (15-59 years old) and 3 207 elderly (≥60 years old). Data from the optimal single-day lag effect of GAM showed that,with every 10 increase of AQI, the percent of increase on the onsets of overall, male, female and adult; tuberculosis cases were 0.85% (95%CI: 0.26%-1.44%), 0.83% (95%CI: 0.24%-1.42%), 0.93% (95%CI: 0.24%-1.62%) and 0.88% (95%CI: 0.29%-1.46%), respectively. The optimal lag time of the single-day effects were 15 days (lag15), but 16 days (lag16) for male. The optimal cumulative lag effect showed that with every 10 AQI increase, the percent of increase on the onsets of overall, male, female and adult tuberculosis cases were 1.92% (95%CI: 0.23%-3.16%), 1.94% (95%CI:0.15%-3.72%), 2.04% (95%CI: 0.10%-3.97%) and 2.00% (95%CI: 0.30%-3.69%), respectively, with the optimal lag time of cumulative delayed effects as 17 days (lag0_17), 18 days (lag0_18), 16 days (lag0_16) and 17 days (lag0_17), respectively. However, there were no statistical significances noticed in the elderly cases. Conclusion: There was a positive correlation between AQI and the number of TB cases in Beijing, and the effects of AQI on the number of TB cases in different genders and age groups were different.