Objective To understand the distribution of M protein gene (emm) of group A streptococcus (GAS) infections among children in Xicheng District of Beijing. Methods Throat swab samples from scarlet fever and pharyngeal infection cases were collected in sentinel hospitals of Xicheng District, Beijing from 2011 to 2024. GAS strains were isolated and identified, and emm gene was amplified and sequenced by PCR to determine the genotype. The differences in emm genotype between different groups were compared. Results A total of 3 130 throat swab samples were collected, and 400 GAS strains were isolated, with a positive rate of 12.78%. The highest positive rate was 19.93% in 2011. The positive rate of scarlet fever (45.71%) was higher than that of pharyngeal infection (6.14%) (P<0.001). There were 391 emm gene positive strains, and the differences in the positive rate of emm gene among different cases were statistically significant (P<0.001). A total of 7 genotypes and 27 gene subtypes were detected. Among different groups, the emm genotypes were mainly emm12 and emm1. The emm gene subtypes were mainly emm12.00 and emm1.00. Except for some years, the genotypes and their subtypes were dominated by emm12 and emm12.00, and the distribution differences of the two major genotypes and their subtypes were statistically significant from 2011 to 2019 (P<0.001). There were differences in genotypes and subtypes among different age groups (P=0.002). Conclusion The dominant types of emm genes in group A streptococcus infections among children were emm12 and emm1 in Xicheng District of Beijing from 2011 to 2024, and the dominant gene subtypes were emm12.00 and emm1.00. It is necessary to comprehensively strengthen the monitoring of the epidemic situation and genotype, timely grasp the distribution and variation of emm gene.

BACKGROUND: The urban-rural disparities in overweight and obesity among children and adolescents are narrowing, and there is a need for long-term and updated data to explain this inequality, understand the underlying mechanisms, and identify priority groups for interventions. METHODS: We analyzed data from seven rounds of the Chinese National Survey on Students Constitution and Health (CNSSCH) conducted from 1985 to 2019, focusing on school-age children and adolescents aged 7-18 years. Joinpoint regression was used to identify inflection points (indicating a change in the trend) in the prevalence of overweight and obesity during the study period, stratified by urban/rural areas and sex. Annual percent change (APC), average annual percent change (AAPC), and 95% confidence interval (CI) were used to describe changes in the prevalence of overweight and obesity. Polynomial regression models were used to predict the prevalence of overweight and obesity among children and adolescents in 2025 and 2030, considering urban/rural areas, sex, and age groups. RESULTS: The prevalence of overweight and obesity in urban boys and girls showed an inflection point of 2000, with AAPC values of 10.09% (95% CI: 7.33-12.92%, t = 7.414, P <0.001) and 8.67% (95% CI: 6.10-11.30%, t = 6.809, P <0.001), respectively. The APC for urban boys decreased from 18.31% (95% CI: 4.72-33.67%, t = 5.926, P = 0.027) to 4.01% (95% CI: 1.33-6.75%, t = 6.486, P = 0.023), while the APC for urban girls decreased from 13.88% (95% CI: 1.82-27.38%, t = 4.994, P = 0.038) to 4.72% (95% CI: 1.43-8.12%, t = 6.215, P = 0.025). However, no inflection points were observed in the best-fit models for rural boys and girls during the period 1985-2019. The prevalence of overweight and obesity for both urban and rural boys is expected to converge at 35.76% by approximately 2027. A similar pattern is observed for urban and rural girls, with a prevalence of overweight and obesity reaching 20.86% in 2025. CONCLUSIONS The prevalence of overweight and obesity among Chinese children and adolescents has been steadily increasing from 1985 to 2019. A complete reversal in urban-rural prevalence is expected by 2027, with a higher prevalence of overweight and obesity in rural areas. Urgent action is needed to address health inequities and increase investments, particularly policies targeting rural children and adolescents.
Humans ; Child ; Adolescent ; Female ; Male ; Rural Population/statistics & numerical data* ; Overweight/epidemiology* ; Prevalence ; China/epidemiology* ; Pediatric Obesity/epidemiology* ; Obesity/epidemiology* ; Urban Population

Objective: To explore the association between lifestyle and fat mass index (FMI) in different positions of children and adolescents aged 7-18, so as to provide a scientific basis for health promotion in children and adolescents. Methods: A total of 1 531 students aged 7-18 was selected by intentional sampling from 4 schools in Tongzhou District, Beijing from September to December in 2020 and August in 2022. Questionnaire survey was used to collect lifestyle including dietary behavior, moderate to vigorous physical activity, smoke and drink behaviors, sleep time and sleep quality. Dual energy Xray absorptiometry was employed to assess fat mass, and calculated total, android, trunk, hip, gynoid and leg fat mass index (FMI). The ttest and Chisquare test were used to compare the differences of different lifestyle. Logistic regression was used to analysis association between lifestyle and body composition in different positions. Results: Compared with healthy lifestyle, unhealthy lifestyle had higher risk for hightrunk FMI (OR=1.40, P<0.05). After adjusted for sex and age, unhealthy lifestyle had higher risk for hightotal FMI, highandroid FMI, hightrunk FMI (OR=1.37, 1.37, 1.50, P<0.05), compared with healthy lifestyle. Stratified analysis found the associations between unhealthy lifestyle and hightotal FMI, highandroid FMI, hightrunk FMI, and highthigh FMI were only significant in girls with 7-12 years old (OR=2.13, 2.46, 2.13, 2.13, P<0.05). Conclusions Unhealthy lifestyle is associated with hightotal FMI, highandroid FMI and hightrunk FMI. A healthy lifestyle should be maintained during puberty, especially before puberty, to help children and adolescents reduce body fat and promote a balanced distribution of body composition.

Objective: To analyze the prevalence of comorbidity of spinal curvature abnormality and malnutrition among primary and secondary school students aged 10-18 years in Tianjin in 2023, so as to provide scientific basis for the combined prevention of common diseases and multiple diseases among students and the construction of school health system. Methods: In September to October 2023, 31 884 primary and secondary school students aged 10 to 18 years in Tianjin were selected using stratified cluster random sampling. Abnormal spinal curvature in children and adolescents was assessed by Sereening of Spinal Curvature Abnormality of Children and Adolescents, while stunting, wasting, overweight, and obesity were determined according to the Screening for Malnutrition among Schoolage Children and Adolescents and Screening for Overweight and Obesity among Schoolage Children and Adolescents. The χ2 test was used to compare betweengroup differences in coprevalence, and multiple Logistic regression models were used to analyze the risk of different comorbidity types in different clusters. Results: The coprevalence of spinal curvature abnormality and malnutrition among primary and secondary school students in Tianjin was 1.6%, which was higher for girls than boys (1.8%, 1.4%), higher (2.5%) for senior high schools than for junior high schools and elementary schools (2.0%, 0.5%), and higher in rural than in urban areas (2.1%, 1.1%) (χ2=9.45, 141.92, 46.94, P<0.05). Multiple Logistic regression models showed that junior high school girls had a higher risk of incorrect posture comorbid with stunting and wasting (OR=4.52, 95%CI=1.84-11.06) and incorrect posture comorbid with overweight and obesity (OR=2.67, 95%CI=1.74-4.10) than boys, and that scoliosis/sagittal spinal abnormality comorbid with stunting and wasting (OR=0.10, 95%CI=0.02-0.44) risk was lower than that of boys, senior high school girls had a lower risk of scoliosis/sagittal spinal abnormality comorbid with overweight and obesity (OR=0.27, 95%CI=0.11-0.66) (P<0.05). Conclusions The coprevalence of spinal curvature abnormality and malnutrition is specific among primary and secondary school students in Tianjin, and the comorbidity type varies by gender and education stage. There is a need to increase prevention and control of spinal curvature abnormalities in school health working, intensive screening of key populations, and timely intervention.

Objective:To identify a novel reassortant H3N2 avian influenza virus using nanopore sequencing technology and analyze its genetic characteristics.Methods:The positive samples of the H3N2 avian influenza virus, collected from the external environment in the farmers' market of Guangzhou, were cultured in chicken embryos. The whole genome was sequenced by targeted amplification and nanopore sequencing technology. The genetic characteristics were analyzed using bioinformatics software.Results:The phylogenetic trees showed that each gene fragment of the strain belonged to the Eurasian evolutionary branch, and the host source was of avian origin. The HA gene was closely related to the origin of the H3N6 virus. The NA gene was closely related to the H3N2 avian influenza virus from 2017 to 2020. The PB1 gene was closely related to the H5N6 avian influenza virus in Guangxi Zhuang Autonomous Region and Fujian Province from 2016 to 2022 and was not related to the PB1 gene of the H5N6 avian influenza epidemic strain in Guangzhou. The other internal gene fragments had complex sources with significant genetic diversity. Molecular characteristics indicated that the strain exhibited the molecular characteristics of a typical low pathogenic avian influenza virus and tended to bind to the receptors of avian origin. On important protein sites related to biological characteristics, this strain had mutations of PB2-L89V, PB1-L473V, NP-A184K, M1-N30D/T215A, and NS1-P42S/N205S.Conclusions:This study identified a novel reassortant H3N2 avian influenza virus by nanopore sequencing, with the PB1 gene derived from the H5N6 avian influenza virus. The virus had a low ability to spread across species, but further exploration was needed to determine whether its pathogenicity to the host was affected.

To monitor and analyze the molecular variation of the H3N2 influenza virus in Guangzhou during the COVID-19 pandemic, respiratory samples of influenza-like cases from influenza monitoring sentinel hospitals were collected from influenza monitoring sentinel hospitals for virus isolation and whole genome sequencing. The results showed that during COVID-19, there was only one peak of H3N2 influenza in the second quarter of 2022 in Guangzhou (the positive rate was 52.23%), and the epidemic intensity and duration were both higher than those in 2019. The HA gene and NA gene of the epidemic strain in Guangzhou in 2022 belonged to the 3C.2a1b. 2a. 1a. 1 branch, which had a good antigenic site matching with the vaccine strain (A/Cambodia/e0826360/2020) from 2021 to 2022 and had no antigen drift. In 2022 strains, the variation of antigen determinant mainly occurred in the I48T of C region, while no variation occurred in the A, B, D, and E regions. The binding site of the HA protein receptor was consistent with the vaccine strain (A/Cambodia/e0826360/2020). Most of the strains in 2022 carried 13 glycosylation sites on the HA protein, but an outbreak of strains caused a loss of glycosylation sites at 24-NST. In conclusion, the strains that caused the epidemic of H3N2 influenza in Guangzhou in 2022 were not evolved or transmitted from the local strains in 2019 during the COVID-19 pandemic.

To monitor and analyze the molecular variation of the H3N2 influenza virus in Guangzhou during the COVID-19 pandemic, respiratory samples of influenza-like cases from influenza monitoring sentinel hospitals were collected from influenza monitoring sentinel hospitals for virus isolation and whole genome sequencing. The results showed that during COVID-19, there was only one peak of H3N2 influenza in the second quarter of 2022 in Guangzhou (the positive rate was 52.23%), and the epidemic intensity and duration were both higher than those in 2019. The HA gene and NA gene of the epidemic strain in Guangzhou in 2022 belonged to the 3C.2a1b. 2a. 1a. 1 branch, which had a good antigenic site matching with the vaccine strain (A/Cambodia/e0826360/2020) from 2021 to 2022 and had no antigen drift. In 2022 strains, the variation of antigen determinant mainly occurred in the I48T of C region, while no variation occurred in the A, B, D, and E regions. The binding site of the HA protein receptor was consistent with the vaccine strain (A/Cambodia/e0826360/2020). Most of the strains in 2022 carried 13 glycosylation sites on the HA protein, but an outbreak of strains caused a loss of glycosylation sites at 24-NST. In conclusion, the strains that caused the epidemic of H3N2 influenza in Guangzhou in 2022 were not evolved or transmitted from the local strains in 2019 during the COVID-19 pandemic.

Objective: To describe the current status of the prevalence of co-morbid myopia and obesity among 7-18 years students in the Inner Mongolia Autonomous Region in 2021 and to analyze the moderating effect of lifestyle in this association ，so as to provide scientific basis for the establishment of the mechanism of Co-morbidity，Shared Etiology，and Shared Prevention of common diseases in children and adolescents. Methods: A total of 139 630 primary and secondary school students aged 7-18 years from Inner Mongolia Autonomous Region were selected by stratified random cluster sampling method in September,2021. Myopia was determined using distance visual acuity examination and refractive error examination, and obesity was determined according to the BMI classification criteria for overweight, obesity screening of Chinese school age children and adolescents. Used a questionnaire, healthy lifestyles were determined according to the American Heart Association s Healthy Lifestyle Score by totaling the six scores for smoking, alcohol consumption, diet, exercise, screen time, and sleep duration.The χ 2 test was used to compare the association between group differences in the co-morbidity rate of myopia and obesity. The multivariable Logistic regression model was used to explore the influencing factors of the co-morbidity of myopia and obesity, and the stratified analysis was used to analyze the moderating effect of lifestyles on the prevalence of the co-morbidity. Results: The prevalence of myopia and obesity co-morbidity among students aged 7-18 years old in the Inner Mongolia Autonmous Region in 2021 was 13.7%, higher among boys than girls ( 15.5 % vs. 11.8%), higher among those aged 10-12 years old than 7-9,13-15,and 16-18 years old (14.7%,13.7%, 13.3%, 12.0%), higher among other ethnic minorities than Han Chinese and Mongolians (15.3%, 14.0%, 12.5%), higher in urban areas than that in suburban areas(15.3%, 13.0%), and middle economic level tracts were higher than poor and good tracts (14.8%, 12.9 %, 12.6%) ( χ 2=392.37，115.73，62.80，119.02，121.60, P <0.05). Multivariable Logistic regression modeling showed that unhealthy lifestyles ( OR=1.24, 95%CI=1.19-1.29 ) and middle level of lifestyle score ( OR=1.15, 95%CI=1.10-1.19 ) students had higher prevalence of co-morbidity, and the results were statistically significant among both boys and girls, the age groups of 10- 12, 13-15, and 16-18 years old, as well as the Han and Mongolian ethnic groups (all P <0.05). Conclusion In 2021, the current situation of myopia and obesity co-morbidity and unhealthy lifestyles among primary and secondary school students in the Inner Mongolia Autonomous Region are not optimistic.

Objective:To describe the prevalence of psychological distress and to analyze its influencing factors among Chinese children and adolescents aged 9-18 years in 2019.Methods:Data was from the 2019 Chinese National Survey on Students' Constitution and Health, and 148 892 children and adolescents were included. Psychological distress was measured using the Kessler Psychological Distress Scale (K10): scores ≤19 were defined as no psychological distress, scores between 20-24 were defined as mild psychological distress, scores between 25-29 were defined as moderate psychological distress, and scores ≥30 were defined as severe psychological distress (moderate to severe psychological distress were defined as high psychological distress). The ANOVA, t test, and χ2 test were used to compare the differences in K10 scores and high psychological distress rates among children and adolescents with different characteristics. The ANOVA and trend χ2 test were used to analyze the trends. Modified-Poisson regression models were used to determine influencing factors of high psychological distress. Results:The K10 scores for Chinese children and adolescents aged 9-18 years in 2019 was 21.5±9.2, and their rate of high psychological distress was 31.6%. The rates of high psychological distress among children and adolescents aged 9-12, 13-15, and 16-18 years were 22.3%, 35.9%, and 38.8%. K10 scores and rates of high psychological distress showed an increasing trend as age increased (trends test all P<0.001). K10 scores and rates of high psychological distress were higher among children and adolescents who were older, female, rural, in areas with medium to low GDP per capita level, and with lower parental education (all P<0.001). Multifactorial modified-Poisson regression analysis showed that children and adolescents aged 13-15 years, 16-18 years, female, rural, and in areas with low to moderate GDP per capita level were at higher risk of high psychological distress (all P<0.05), with a OR (95% CI) of 1.55 (1.52-1.58), 1.66 (1.63-1.69), 1.07 (1.05-1.09), 1.02 (1.01-1.04), 1.10 (1.07-1.12). Children and adolescents in areas with medium to high GDP per capita level, whose father had a secondary or high school degree, whose father had a college degree or above, whose mother had a secondary or high school degree, and whose mother had a college degree or above were at lower risk of high psychological distress (all P<0.05), with a OR (95% CI) of 0.96 (0.94-0.98), 0.92 (0.90-0.93), 0.84 (0.82-0.86), 0.95 (0.93-0.97), 0.86 (0.83-0.88). Conclusions:The prevalence of psychological distress was high among Chinese children and adolescents aged 9-18 years in 2019, which is a vital problem. Mental health interventions need to be implemented among children and adolescents that were older, girls, rural, live in areas with lower economic levels, and whose parents have a lower education level.

Objective:To analyze the association between the occurrence of spermarche and menarche and psychological distress among Chinese Han children and adolescents aged 9 to 18 years.Methods:Data were drawn from the 2019 Chinese National Survey on Students' Constitution and Health, and a total of 54 438 boys aged 11 to 18 years and 76 376 girls aged 9 to 18 years with psychological distress, spermarche/menarche records were included in the final analysis. The occurrence of spermarche/menarche was recorded by physicians, and psychological distress was classified according to the Kessler Psychological Distress Scale scores. The chi-square test was used to compare the difference between groups in the occurrence of spermarche/menarche, and the multinomial logistic regression model and stratification analysis was established to analyze the association between psychological distress and spermarche/menarche.Results:The incidence of spermarche/menarche in 2019 ranged from 6.3% to 96.5% for eight age groups of Chinese boys and 2.8% to 99.0% for ten age groups of girls. The rates of high psychological distress among boys and girls were 32.5% and 32.7%. Among boys aged 11 to 18 years, the rate of high psychological distress increased with age, with a trend test P<0.001, and the difference in the rate of high psychological distress between those who had and had not had their spermarche was not statistically significant in all age groups. Among girls aged 9 to 18 years, the rate of high psychological distress increased with age, with a trend P<0.001; the rate of high psychological distress was higher in the group with menarche at age 10 and 12 than in the group without menarche (all P<0.05). High psychological distress was positively correlated with spermarche among boys aged 13-15 years living in urban areas and hight level economic development areas ( OR=1.11, 95% CI: 1.02-1.21; OR=1.18, 95% CI: 1.06-1.32). Overall, high psychological distress was positively correlated with menarche in girls aged 9-12 and 13-15 years ( OR=1.33, 95% CI: 1.25-1.42; OR=1.22, 95% CI: 1.07-1.39). High psychological distress was positively correlated with menarche among girls aged 9-12 years living in different regions except for the Northeast region, in areas with different levels of economic development, and in urban and rural areas, in girls aged 13-15 years living in urban, central, and western regions, and in girls aged 16-18 years residing in the central region. Conclusions:This study found an association between the occurrence of spermarche/menarche and psychological distress among Chinese Han children and adolescents aged 9 to 18 years in 2019, which was particularly significant among girls aged 9 to 12 years and boys aged 13 to 15 years living in areas with higher levels of socioeconomic development.