Objective To explore the impact of meteorological factors on the incidence of scarlet fever in Xicheng District of Beijing, and to provide a scientific basis for formulating targeted prevention and control measures. Methods Daily scarlet fever incidence data and corresponding meteorological data from 2010 to 2019 in Xicheng District of Beijing were collected. Using year, month, and day of the week as time-stratified variables, a conditional logistic regression model with a time-stratified case-crossover design was employed to analyze the impact of different meteorological factors on the number of scarlet fever cases in Xicheng District, while controlling for long-term trends, seasonality and other confounding factors. Results From 2010 to 2019, a total of 3,195 cases of scarlet fever were reported in Xicheng District, with an average annual incidence rate of 24.17/100 000. The overall trend showed fluctuating decline, during which three incidence peaks occurred, with the highest incidence rate observed in 2011. No severe or fatal cases were reported. The incidence of scarlet fever exhibited a distinct seasonal bimodal distribution, primarily concentrated between April to June and November to January of the following year. The conditional logistic regression results showed that the average relative humidity and average temperature were positively correlated with scarlet fever cases (β=0.0203, β=0.0613, P＜0.001), while the average vapor pressure was negatively correlated with scarlet fever cases (β=-0.1468, P＜0.001). Increases average relative humidity and average temperature were risk factors for scarlet fever incidence (OR=1.0205，95%CI=1.0150 -1.0261；OR=1.0632，95%CI=1.0379 -1.0891). For every 1.00% increase in average relative humidity, the number of scarlet fever cases increased by 2.05% (1.50% –2.61%). Similarly, for every 1^。C rise in average temperature, the number of cases increased by 6.32% (3.79% – 8.91%). In contrast, an increase in average vapor pressure had a protective effect against scarlet fever (OR=0.8635,95%CI=0.8392-0.8885). For every 1 hPa increase in average vapor pressure, the number of scarlet fever cases decreased by 13.65% (11.15%–16.08%). Conclusion The average relative humidity, average temperature and average vapor pressure are the primary meteorological factors influencing the incidence of scarlet fever in Xicheng District of Beijing, and can be utilized as indicators for the prevention, control, surveillance and early warning of scarlet fever.

Objective: To explore the comorbidity and associated factors of dental caries and overweight/obesity among primary and secondary school students in Guangxi, so as to provide a scientific basis for the development of targeted prevention strategies. Methods: A stratified cluster random sampling method was used to survey 178 700 students from the fourth grade of primary school to the third year of high school in Guangxi Zhuang Autonomous Region from September to November 2023, including physical examination, oral screening, and questionnaire survey. Chisquare tests and binary Logistic regression analysis were employed to investigate the related factors of the cooccurrence of dental caries and overweight/obesity among students. Results: The comorbidity rate of dental caries and overweight/obesity was 9.55%, with urban areas (9.95%) higher than rural counties (9.24%), boys (10.54%) higher than girls (8.54%), primary school students (11.49%) higher than senior high school students (8.92%) and junior high school students (8.05%), and nonboarding students (11.44%) higher than boarding students (7.94%), and all differences were statistically significant (χ2=26.07, 207.91, 471.54, 629.14,P<0.01). Multivariate Logistic regression analysis showed that consuming cereal for breakfast (OR=0.91, 95%CI=0.88-0.94), drinking milk in the past week (OR=0.89, 95%CI=0.83-0.95), meeting sleep standards (OR=0.95, 95%CI=0.91-0.99), and brushing teeth at least once a day (OR=0.82, 95%CI=0.73-0.93) had a lower risk of the comorbidity of dental caries and overweight/obesity. In contrast, drinking beverages in the past week (OR=1.14, 95%CI=1.09-1.20), consuming fried foods in the past week (OR=1.11, 95%CI=1.06-1.17), eating fruit ≥1 time every day (OR=1.06, 95%CI=1.02-1.11), consuming fruit ≥1 type every day (OR=1.07, 95%CI=1.01-1.12), and having fish, poultry, meat, or eggbased breakfasts (OR=1.03, 95%CI=1.05-1.13) had a higher risk of the comorbidity of dental caries and overweight/obesity (P<0.05). Conclusions Dietary habits and lifestyle behaviors are associated with the comorbidity of dental caries and overweight/obesity among primary and secondary school students in Guangxi. Guiding students to form healthy living habits is helpful to preven dental caries and overweight/obesity.

Objective: To investigate the prevalence and associated factors of spinal curvature abnormalities among primary and secondary school students in the Guangxi Zhuang Autonomous Region, so as to provide a scientific basis for the prevention and control of such abnormalities. Methods: From September to November 2023, adopting a stratified cluster random sampling method, spinal curvature screenings and questionnaire surveys were conducted among 168 931 students from grade 4 of primary school to grade 12 of high school in 111 districts and counties across 14 cities in Guangxi. Chi square tests and binary Logistic regression analysis were used to analyze influencing factors of spinal curvature abnormalities. Results: In 2023, the detection rate of poor posture among students above grade 4 in Guangxi was 4.24% , and the detection rate of spinal curvature abnormalities was 2.13%. The detection rate was higher among urban students (2.84%) than rural students (1.66%), boarding students (2.61%) than non-boarding students (1.60%), and high school students (3.16%) than junior high (2.45%) and primary school students (1.15%), and the differences were statistically significant ( χ 2=269.85, 221.44, 565.10, P <0.01). A trend of increasing detection rates with higher grade levels was observed ( χ 2 trend =617.63, P <0.01). Binary Logistic regression analysis indicated that students without boarding at school ( OR =0.82, 95% CI =0.75-0.90), engaging in high-intensity physical activity for over 60 min per day ≥5 days per week ( OR =0.90, 95% CI =0.82-0.98), and adequate sleep ( OR =0.87, 95% CI =0.81-0.94) had lower risks of detecting spinal curvature abnormalities ( P <0.05). Conclusions The prevalence of spinal curvature abnormalities increases with grade level among primary and secondary school students in Guangxi. Regular moderate-to-vigorous physical activity demonstrates protective effects against spinal abnormalities.

Objective: To investigate the association between medium to long term PM 2.5 exposure around school areas and overweight/obesity among primary and secondary school students in Guangxi, providing data support and theoretical foundations for scientifically addressing overweight and obesity in primary and secondary school students. Methods: From September to November 2023, a stratified cluster random sampling method was employed to select 251 183 students aged 7-18 years (grade 1 to grade 12) from 14 prefecture level cities (111 districts and counties) in Guangxi. PM 2.5 mass concentration data were obtained from the Tracking Air Pollution in China (TAP) dataset. Preliminary comparative analysis was conducted using the Mann-Whitney U test, while binary Logistic regression models were applied to quantify the relationship between PM 2.5 exposure and overweight/obesity. Restricted cubic spline analysis was further utilized to examine the nonlinear association between PM 2.5 concentration and overweight/obesity risk. Results: The detection rate of overweight/obesity among Guangxi students in 2023 was 19.5%. The median PM 2.5 concentration in the year prior to the study was higher in the overweight/obesity group (23.22 μg/m 3) compared to the non overweight/obesity group (22.63 μg/m 3) ( Z=-15.66, P <0.01), and consistent trends were observed across gender (male/female) and educational stage (primary/junior/senior high school) subgroups (all P <0.01). Binary Logistic regression revealed that for every 10 μg/m 3 increase in the annual average PM 2.5 concentration, the risk of overweight/obesity increased by 12% ( OR=1.12, 95%CI=1.09- 1.15 , P <0.01). Restricted cubic spline analysis indicated a nonlinear relationship between monthly PM 2.5 levels and overweight/obesity risk ( P trend <0.01). Below 22.68 μg/m 3, PM 2.5 exposure showed no significant association with obesity risk; above the threshold, the risk increased with rising PM 2.5 levels. Conclusion Medium to long term PM 2.5 exposure around school environments is significantly associated with overweight/obesity among primary and secondary school students.

Objective: To analyze the association between altitudes and nutritional status of children and adolescents, and to explore the moderating effects of dietary behaviors and physical activity, so as to provide a scientific basis for developing lifestyle interventions tailored to local conditions. Methods: From September to November 2023, physical examinations and questionnaire surveys were conducted among children and adolescents aged 7-17 in two autonomous regions, Inner Mongolia and Xizang, with a final sample of 156 511 participants by the stratified cluster random sampling method. Height and weight were measured to calculate body mass index (BMI). Sociodemographic characteristics, dietary behaviors, and physical activity were collected via questionnaires, while the altitude of each participant s school was obtained using Amap. Logistic regression was performed to examine the relationship between altitudes and nutritional status. Interaction terms and stratified analyses were applied to assess the moderating effects of dietary behaviors and physical activity. Restricted cubic spline (RCS) were used for visualization. Results: In 2023, the prevalence of wasting and overweight/obesity among children and adolescents in Xizang were 9.7% and 9.0%, respectively, compared to 2.9% and 22.0% in Inner Mongolia. Logistic regression analysis results showed that for every 1 km increase in altitude, the risk of wasting increased, while the risk of overweight/obesity decreased ( OR =1.43, 0.19, both P <0.05). The results of the stratified analysis showed that compared to those living at altitudes <1 km, children and adolescents with healthy diets showed no significant association between altitudes (1-<2 and 2-<3 km) and wasting ( OR =1.22, 0.75, both P >0.05), whereas significant associations were observed at 3-<4 and ≥4 km altitudes ( OR =2.25, 2.89, both P <0.05). In contrast, unhealthy dietary groups showed statistically significant associations across altitudes ( OR =1.18-4.04, all P <0.05), consistent with RCS results. No moderating effects were observed for physical activity on the altitude wasting association or for dietary behaviors and physical activity combined on the altitude overweight/obesity association ( P interaction =0.63, 0.10, 0.53). Conclusion Healthy dietary behaviors play a critical role in improving the nutritional status of children and adolescents and reducing regional disparities, providing a scientific foundation for public health policy formulation and implementation.

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

BACKGROUND: Parental myopia is an important risk factor for myopia in Chinese children and adolescents. This study aimed to assess the influence of parental myopia and the severity of myopia on offspring and to evaluate whether adopting healthy lifestyles can mitigate the effects of parental myopia on offspring. METHODS: This cross-sectional study analyzed data from children and adolescents aged 6-17 years with complete vision assessments and parental history of myopia from six provinces in China during 2013-2014. Parental demographic information, children's outdoor activity time, sleep time, and sedentary time were collected via questionnaire. Parental myopia was classified as no myopia, paternal myopia, maternal myopia, and both. The offspring were categorized into 10 groups based on parental myopia prescription. Associations of the above factors with myopia in children and adolescents were evaluated by logistic regression analysis. RESULTS: Among 40,864 children and adolescents (50.3% boys and 49.7% girls), 22,537 (55.2%) were diagnosed with myopia. In comparison to offspring devoid of parental myopia, children with one parent affected by myopia exhibited odds ratio (OR) of 1.75 (95% confidence interval [CI]: 1.62-1.88) for myopia, while those with both parents affected showed OR of 2.27 (95% CI: 2.02-2.55) after adjusted for lifestyle factors. The likelihood of myopia in offspring increased with increasing severity of parental myopia, with a 3.08-fold increase in risk observed when both parents presented high myopia. Nonetheless, children adhering to two or more healthy lifestyle factors demonstrated a diminished risk of myopia compared with those with fewer than two lifestyle factors, especially among offspring of non-myopic or mildly myopic parents. CONCLUSIONS Parental myopia has a dose-dependent association with their offspring. Healthy lifestyles may reduce the impact of parental factors on myopia in offspring. The observed associations suggest that although the genetic burden of parental myopia cannot be ignored, healthy lifestyles and nurturing are also very important.
Humans ; Myopia/epidemiology* ; Child ; Male ; Female ; Adolescent ; Cross-Sectional Studies ; China/epidemiology* ; Parents ; Surveys and Questionnaires ; Risk Factors

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.

Abstract Spinal curvatures has emerged as the third major chronic condition seriously threatening the physical and mental health of Chinese children and adolescents, with significant regional differences. Its etiology is complex and diverse, and early prevention and treatment are feasible, whereas treatment in later stages entails considerable difficulty and economic burden. Currently, the prevention and control of student spinal curvatures has been elevated to a national health strategy. A series of policy documents have been successively issued, and it has greatly facilitated the institutionalization and normalization of national routine screening for student spinal curvatures. However, it is still inadequate considering current prevention and control system for spinal curvatures in children and adolescents. There is an urgent need to establish a closed loop model based on China s institutional advantages, comprising Initial Screening-Diagnosis-Treatment-Preventive Control-Followup Assessment, to strengthen the safeguarding of spinal health in children and adolescents.

Abstract Currently, the school health system in China is transitioning from basic safeguarding to comprehensive health management and has been elevated to a national strategic level. However, the diversification of students health issues and the imbalance in resource allocation remain major challenges. To address issues such as adolescent myopia, obesity, spinal curvature, mental health, and infectious diseases, there is an urgently need to build a highlevel school health system that encompasses multiple aspects such as resource allocation optimization, professional skill enhancement, and health education improvement. Simultaneously, it is need to deepen the research and implementation of common disease prevention strategies for students. It will play a vital role in promoting the construction of Healthy China, the modernization of education, and the establishment of a highquality disease control system.