In November 2017, Guangzhou implemented a self-paid two-dose varicella vaccination program. This study evaluated the program's impact on varicella incidence trends across the general population and specific age groups. An interrupted time-series analysis was conducted using surveillance data from January 2011 to December 2024. The pre-intervention period spanned 2011-2017, and the post-intervention period 2018-2024. Seasonal-trend decomposition and segmented regression were employed to analyze changes in level and trend of varicella incidence. A total of 225,497 varicella cases were reported between 2011 and 2024. The annual incidence rate decreased by 28.1% from the pre-intervention to post-intervention period, from 126.80 to 91.14 per 100,000 population. Prior to intervention, there was no evidence of a monthly change in varicella incidence (0.3%; t = 2.27, P = .294). Significant upward trends were observed among 10-14-y-olds and ≥20-y-olds (0.6% monthly increase, both P < .01). Post-intervention, a significant monthly decrease of 1.8% was observed overall (t = -9.956, P < .001). The most pronounced reduction occurred in 4-6-y-olds (3.8% monthly decrease), followed by 7-9-y-olds (3.0%), 0-3-y-olds (2.3%), 10-14-y-olds (1.9%), ≥20-y-olds (1.1%), and 15-19-y-olds (0.5%). Varicella incidence exhibited consistent seasonal variation, with a primary peak occurring from October to January. The two-dose varicella vaccination program was associated with a significant reduction in varicella incidence across all age groups in Guangzhou, demonstrating both direct protection among vaccinated children and indirect herd effects in older populations. These findings support incorporating the two-dose varicella vaccine into routine national immunization programs.

This study investigated the epidemiological and spatiotemporal characteristics of scarlet fever in Guangzhou, China, and provided a scientific basis for the formulation and optimization of prevention and control strategies. The epidemiological profile of scarlet fever was systematically reviewed using descriptive analysis. We used the Moran’s I, local indicators of spatial association, and the retrospective spatiotemporal scanning statistical analysis to study the spatiotemporal aggregation phenomenon of scarlet fever in Guangzhou. From 2005 to 2024, 9,601 scarlet fever cases were reported within Guangzhou, with an annual average morbidity of 3.16 per 100,000. Joinpoint regression analysis indicated a statistically significant overall upward trend in scarlet fever incidence (AAPC = 17.26

Dengue fever, an acute Aedes-borne infectious disease caused by the dengue virus (DENV), is a substantial global health challenge, necessitating the development of swift and effective surveillance methodologies. We have developed a Recombinase Aided Amplification (RAA)-Cas12a assay that exhibits superior analytical sensitivity compared with real-time PCR while maintaining comparable specificity. In clinical specimen testing, the assay demonstrated a sensitivity of 92.3% and a specificity of 100%, using a signal-to-noise ratio of >= 2.0 as the positivity threshold. Furthermore, the RAA-Cas12a assay displayed remarkable sensitivity in detecting DENV in both adult and larval mosquitoes, with field data from mosquito surveillance aligning closely with the emergence of local dengue cases. Characterized by its simplicity, rapidity, and precision, the RAA-Cas12a approach emerges as a highly promising technology for monitoring virus carriage in field-collected mosquitoes, thereby functioning as both an early warning system and a crucial indicator for effective dengue outbreak management. The practicality and cost-effectiveness of this methodology provide a robust foundation for the establishment of an efficient global collaborative surveillance and risk assessment platform to mitigate the rapid spread of dengue.

GISDD, the Global Integrated Sequence and Genotyping Database for Dengue Virus (DENV), provides an integrated online analysis platform encompassing tools such as GISDDrlearn, GISDDprimer, and GISDDref, enabling swift identification and tracing of well-established DENV genotypes, subgenotypes, and clades, thereby facilitating a stratified global coordinated surveillance strategy.

Background Influenza is a significant public health issue, particularly for vulnerable groups like children and the elderly. Despite widespread vaccination and public health measures, age-specific incidence data-crucial for targeted interventionsu2014are limited in many areas, including Guangzhou. The epidemiological patterns of influenza have also been affected by non-pharmaceutical interventions during the COVID-19 pandemic, underscoring the need for updated local estimates. This study aimed to estimate the age-specific incidence of influenza infection in Guangzhou from 2019 to 2022u2014a period covering both pre-pandemic and pandemic phasesu2014to inform regionally tailored prevention and control strategies. Methods This study analyzed surveillance data on influenza-like illness (ILI) and virological test results from sentinel hospitals in Guangzhou covering the period from 2019 to 2022. A previously established multiplier model was employed, which integrated age-specific consultation rates, influenza positivity rates, as well as parameters related to symptom presentation and detection sensitivity. Monte Carlo simulations were utilized to estimate annual age-stratified influenza infection and incidence rates, accompanied by 95% confidence intervals. The population denominators were derived from the national census conducted in 2020. Results 7.78% of the total population in Guangzhou were infected by influenza in 2019, 1.40% in 2020, 1.85% in 2021 and 12.13% in 2022 and incidence rates were 5.15% in 2019, 0.93% in 2020, 1.23% in 2021 and 8.04% in 2022. The highest influenza infection and incidence rates were observed in 2022 and the lowest in 2020. Infections in the 0u201314 age group were 27.19%, 3.57%, 11.16% and 66.15% during 2019u20132022 and respective incidence rates were 18.00%, 2.37%, 7.41% and 43.84%. Conclusions 0u201314-year-old infants and children were the main victims of influenza. Targeted strategies should be developed to prevent the spread in this age group.

OBJECTIVE:To examine whether influenza transmission risk decreased during summer and winter vacations and increased after vacations and statutory holiday. DESIGN:An ecological study. SETTING:Guangzhou, Guangdong Province of China. PARTICIPANTS:A total of 458 343 influenza cases in school-aged children were included, including 160 067 (35.05%) in kindergarten, 223 817 (48.83%) in primary school, 50 053 (10.92%) in middle school and 23 801 (5.19%) in high school. DATA AND METHODS:Data on influenza cases were obtained from the Notifiable Infectious Disease Surveillance System operated by Guangzhou Centre for Disease Control and Prevention. Influenza incidence rate ratio (IRR) by negative binomial regression model was used to analyse the influenza risk of school-age children during/after vacation to before/during breaks. RESULTS:In all four groups, there was significantly lower incidence of influenza during winter and summer vacations compared with the 4 weeks preceding vacations. Compared with the 2 weeks preceding return, kindergarten students experienced the highest influenza risk in the third week after summer vacation (IRR=3.40, 95% CI 2.43to 4.79). Primary school students had the highest risk in the fourth week after winter vacation (IRR=9.59, 95% CI 6.71 to 13.87). Middle school students had the highest risk in the fourth week after summer (IRR=11.60, 95% CI 6.17 to 22.62). High school students also experienced the highest risk in the fourth week following summer (IRR=17.96, 95% CI 8.10 to 42.05). Despite the risk of influenza increasing after returning to school, it remained lower compared with before vacations and holidays. CONCLUSIONS:Due to changes in contact patterns, influenza incidence was high towards the end of term, significantly decreased during vacations and started to rise on returning to school, peaking in the third or fourth week. These findings suggested using holiday periods strategically to promote influenza vaccination and implementing enhanced non-pharmaceutical interventions on students returning to school.

Acute stress disorder (ASD) among people ever infected with COVID-19 (PEIC) is prevalent and may lead to post-trauma stress disorder. Soon after China relaxed her COVID-19 control measures in November/December 2022, the infection rate surged rapidly, creating huge uncertainty and stressful situations. Little is known about situations regarding ASD at the ending phase of the pandemic. Potential personal cognitive/emotional factors and environmental factors of ASD were investigated in this study. A cross-sectional study was conducted among 5,545 PEIC aged 18-60 years from December 27, 2022 to January 9, 2023 living in seven cities of China. The 5-item Chinese version of the Primary Care PTSD Screen was used to assess ASD. Multiple logistic regression analyses were performed to identify factors of ASD. The prevalence of ASD was 21.2%. Adjusted for the background variables, significant personal cognitive risk factors (COVID-19 infection severity, perceived high reinfection risk and perceived weak natural immunity acquired), emotional risk factors (worry about the long-term physical harms, and panic about infection of elderly or young family members), and significant environmental risk factors (difficulties in getting information and medical supplies, having unvaccinated old/young family members, and having significant others suffering from severe COVID-19 symptoms) were identified. The prevalence of ASD among PEIC was noticeable. It is warranted to identify those at high risk of developing ASD and provide them with care and early interventions to prevent deterioration. Such programs may consider modifying the risk factors found in this study.

Dengue fever remains a significant public health challenge in Guangzhou, China, where healthcare-seeking behavior plays a critical role in shaping disease outcomes. This study investigates patterns of consultation delays and their determinants among locally acquired dengue cases from 2015 to 2024, aiming to inform targeted public health interventions. Surveillance data on locally acquired dengue fever cases in Guangzhou were extracted from Chinese National Notifiable Infectious Disease Reporting Information System for analysis. Categorical variables were summarized as frequencies and percentages (N,

Objective To understand the epidemiological characteristics of human respiratory syncytial virus(HRSV)infection in Guangzhou city.Methods Data were sourced from two parts:national influenza sentinel surveillance and Guangzhou city's acute respiratory infection cluster surveillance.Sentinel surveillance data,collected from August 2023 to July 2024,included outpatient and emergency department influenza-like illness(ILI)cases and hospitalized severe acute respiratory infection(SARI)cases from four national-level influenza sentinel hospitals in Guangzhou.Cluster surveillance data,from 2021 to 2023,included acute respiratory infection(ARI)clusters caused by HRSV in Guangzhou.Respiratory specimens were collected from cases for multiple respiratory pathogen nucleic acid testing.The HRSV positive detection rate among sentinel surveillance cases was calculated,and indicators such as the HRSV infection attack rate among children in cluster settings were comparatively analyzed.Results The overall HRSV positive detection rate among the included sentinel surveillance cases was 3.75%(51/1 360).Among the positive cases,68.63%(35/51)were children under 5 years old,with the highest positive detection rate observed in the<6 months age group(10.29%,7/68).The HRSV positive detection rate among hospitalized SARI cases in this age group was as high as 31.25%(5/16).Two HRSV epidemics occurred in Guangzhou,one in the summer and autumn of 2023(August-September)with subtype A as the dominant strain,and the other in the spring of 2024(February-April)with subtype B.All four monitored HRSV-induced ARI clusters occurred in summer;three in postpartum care centers and one in a childcare facility.The overall attack rate among children was 42.42%(84/198).The overall asymptomatic infection rates among mothers and staff in these facilities were 83.33%(5/6)and 82.35%(14/17),respectively.Positive environmental samples from postpartum care centers were mainly from infant common areas or nursing areas.Conclusions HRSV epidemics in Guangzhou show clear seasonality.Children under 5 years old,especially infants under 6 months,are the main population affected by HRSV infection and hospitalization.Postpartum care centers and childcare facilities are prone to HRSV clusters.Timely detection of asymptomatic infections and effective environmental cleaning and disinfection are crucial for epidemic control.

BACKGROUND:Recombinant B-subunit/Whole Cell Cholera Vaccine (rBS/WC) represents a new and effective way to protect against and control diarrhea. A test-negative case-control study was conducted to investigate the cross-protective effect of cholera vaccine immunization against bacterial infectious diarrhea in a real-world setting. METHODS:Using a test-negative design, children aged 2-6 years with infectious diarrhea in Guangzhou City were selected as study subjects. A 1:4 propensity score matching based on the basic characteristics of the included study subjects, and vaccine effects were calculated after correcting for confounders. RESULTS:A total of 2796 children with laboratory-confirmed infectious diarrhea were enrolled in the study, and 316 pairs were successfully enrolled in the matching after Propensity Score Matching(PSM), totaling 1306. By conditional logistic regression analysis, The results showed that the total protective effect of ≥1 dose of rBS/WC vaccine against bacterial infectious diarrhea in children aged 2-6 years was 57.7 % (95 % CI: 30.3-74.3); the rBS/WC vaccine had the best protective effect of 74.8 % (95 % CI: 16.8-95.6) within 6 months of vaccination and then showed a decreasing trend. The vaccine's protective effect was 54.6 % (95 % CI: 22.1-73.5) against Salmonella and 69.2 % (95 % CI: -133.7-95.9) against Escherichia coli. Stratified analyses revealed higher point estimates of the protective effect obtained by vaccination among healthy children with good hygiene. CONCLUSIONS:These findings support the idea that the rBS/WC vaccination program is effective in the real world in preventing bacterial diarrhea in children. For people who are susceptible to bacterial diarrhea, the cholera vaccine is a good preventive option.

Background This acute gastroenteritis outbreak represents the most extensive norovirus cluster reported in Guangzhou long-term care facilities in recent years. In order to control the outbreak, an epidemiological investigation was conducted to determine the causative agent, sources, role of transmission and risk factors of the infections while providing technical guidance to the institution for implementing infection control measures. Methods An epidemiological investigation was carried out for cases among elderly residents and staff members in the long-term care facility. A case-control study was conducted. Information on basic demographic characteristics, clinical presentations, exposure history, care giving interactions, off-site activities, participation in congregate events, kitchen staff health status, food hygiene, and drinking water hygiene was collected. Multivariate analysis was used to analyze risk factors. Rectal swabs of the cases and staff members, as well as environmental samples were collected to detect potential viruses and bacteria. Genotyping and environmental surveillance were implemented to delineate transmission pathways. Results The overall attack rate was 17.72% (126/711), including 554 elderly residents and 157 staff members. Key risk factors included requiring partial dressing assistance (adjusted odds ratio [ aOR ] = 1.92, 95% confidence interval [CI] : 1.06, 3.64), sharing dining tables with cases during meals ( aOR = 2.47, 95% CI : 1.54, 3.99), co-residing in dormitories with cases ( aOR = 2.58, 95% CI : 1.60, 4.17), off-site engagements during the pre-outbreak period (December 18–24) ( aOR = 86.03, 95% CI : 17.44, 2076.65). Genotype analysis confirmed norovirus GII.17[P17] in both caregivers and residents. Conclusions Our findings underscore the necessity of implementing infection control strategies, including early "Relative Static Management", rigorous enforcement of environmental disinfection and strict enforcement of caregivers compliance with personal protective equipment use in long-term care facilities.

Background:Influenza is a significant public health issue, particularly for vulnerable groups like children and the elderly. Despite widespread vaccination and public health measures, age-specific incidence data-crucial for targeted interventions-are limited in many areas, including Guangzhou. The epidemiological patterns of influenza have also been affected by non-pharmaceutical interventions during the COVID-19 pandemic, underscoring the need for updated local estimates. This study aimed to estimate the age-specific incidence of influenza infection in Guangzhou from 2019 to 2022-a period covering both pre-pandemic and pandemic phases-to inform regionally tailored prevention and control strategies. Methods:This study analyzed surveillance data on influenza-like illness (ILI) and virological test results from sentinel hospitals in Guangzhou covering the period from 2019 to 2022. A previously established multiplier model was employed, which integrated age-specific consultation rates, influenza positivity rates, as well as parameters related to symptom presentation and detection sensitivity. Monte Carlo simulations were utilized to estimate annual age-stratified influenza infection and incidence rates, accompanied by 95% confidence intervals. The population denominators were derived from the national census conducted in 2020. Results:7.78% of the total population in Guangzhou were infected by influenza in 2019, 1.40% in 2020, 1.85% in 2021 and 12.13% in 2022 and incidence rates were 5.15% in 2019, 0.93% in 2020, 1.23% in 2021 and 8.04% in 2022. The highest influenza infection and incidence rates were observed in 2022 and the lowest in 2020. Infections in the 0-14 age group were 27.19%, 3.57%, 11.16% and 66.15% during 2019-2022 and respective incidence rates were 18.00%, 2.37%, 7.41% and 43.84%. Conclusions:0-14-year-old infants and children were the main victims of influenza. Targeted strategies should be developed to prevent the spread in this age group.

Introduction: Dengue fever represents a significant public health challenge in tropical and subtropical regions worldwide, including China. This study aims to enhance early dengue detection and diagnosis by evaluating healthcare facilities' diagnostic capacity and clinicians' awareness. Methods: In June 2024, surveys were conducted in 11 secondary and higher-level hospitals and 11 community health centers. Data from facilities evaluations and clinician questionnaires were analyzed using chi-square tests and logistic regression. Results: Secondary and higher-level hospitals demonstrated more robust dengue-related institution-building but exhibited deficiencies in suspected case screening and public awareness efforts. Additionally, polymerase chain reaction (PCR) testing capacity was limited to one higher-level hospital, and nonstructural protein 1 (NS1) testing costs were high in secondary and higher-level hospitals, with varying reimbursement rates due to different insurance types and institutional levels. Significant disparities in diagnostic awareness were found across hospital levels, departments, ages, and professional titles (P<0.05). The regression analysis shows that education can significantly enhance diagnostic awareness [odds ratio (OR)=13.780, 95% confidence interval (CI): 2.937, 64.650]. Conclusions: These findings underscore the need for dynamically adjust dengue testing strategies at different epidemic stages and improve NS1 testing cost reimbursement. Also, there should be more efforts in enhancing PCR testing in healthcare facilities and promoting health education.

Seropositivity study of Varicella in Healthy Populations in Guangzhou, China. Infection with varicella-zoster virus (VZV) leads to skin and mucous membranes blisters and the complications can be life threatening. A seroepidemiological study conducted from 2020 to 2022 in Guangzhou, China, aimed to evaluate varicella antibody levels. We measured varicella antibody concentrations using an enzyme-linked immunosorbent assay. A total of 3300 people were enrolled in the study. The mean varicella antibody level was 171.2 mIU/mL (95% CI: 158.9, 184.4), with an overall positivity rate of 67.00% (95% CI: 65.37, 68.60). The mean level of those positive subjective was 581.2 mIU/mL (95% CI: 552.3, 611.5). Varicella antibody levels were found to be influenced by age, vaccination dosage, and history of varicella infection. Antibody level increased with age and the number of vaccinations. The antibody induced by the varicella vaccine remained at protective levels for at least 6 years post-vaccination. We recommend two doses of the varicella vaccine for both children and adults and the integration of the varicella vaccine into the national routine immunization program.

Background Infectious diarrhea remains a major public health problem worldwide. This study used stacking ensemble to developed a predictive model for the incidence of infectious diarrhea, aiming to achieve better prediction performance. Methods Based on the surveillance data of infectious diarrhea cases, relevant symptoms and meteorological factors of Guangzhou from 2016 to 2021, we developed four base prediction models using artificial neural networks (ANN), Long Short-Term Memory networks (LSTM), support vector regression (SVR) and extreme gradient boosting regression trees (XGBoost), which were then ensembled using stacking to obtain the final prediction model. All the models were evaluated with three metrics: mean absolute percentage error (MAPE), root mean square error (RMSE), and mean absolute error (MAE). Results Base models that incorporated symptom surveillance data and weekly number of infectious diarrhea cases were able to achieve lower RMSEs, MAEs, and MAPEs than models that added meteorological data and weekly number of infectious diarrhea cases. The LSTM had the best prediction performance among the four base models, and its RMSE, MAE, and MAPE were: 84.85, 57.50 and 15.92%, respectively. The stacking ensembled model outperformed the four base models, whose RMSE, MAE, and MAPE were 75.82, 55.93, and 15.70%, respectively. Conclusions The incorporation of symptom surveillance data could improve the predictive accuracy of infectious diarrhea prediction models, and symptom surveillance data was more effective than meteorological data in enhancing model performance. Using stacking to combine multiple prediction models were able to alleviate the difficulty in selecting the optimal model, and could obtain a model with better performance than base models.

A seroepidemiological study was conducted in 2018 to assess diphtheria and tetanus antibodies in Guangzhou, China. Diphtheria and tetanus antibody concentrations were measured with an enzyme-linked immunosorbent assay. A total of 715 subjects were enrolled in the study. The overall diphtheria and tetanus toxoid IgG-specific antibody levels were 0.126 IU/mL (95% CI: 0.115, 0.137) and 0.210 IU/mL (95% CI: 0.185, 0.240), respectively; the overall positivity rate was 61.82% (95% CI: 58.14, 65.39) and 71.61% (95% CI: 68.3, 74.92), respectively. The diphtheria and tetanus antibody concentration was decreased by age and increased by doses. The geometric mean concentrations and positivity rate of diphtheria and tetanus antibodies were lowest and below the essential protection level in people over 14 years of age. Compared to children and adolescents, middle-aged people and the aged are at much higher risk of infection with Corynebacterium diphtheriae and Clostridium tetani. The current diphtheria and tetanus immunization schedule does not provide persistent protection after childhood. There is an urgent need to adjust the current immunization schedule.

What is already known about this topic?:The inclusion of meningococcal vaccines in the National Immunization Program (NIP) over several years has significantly reduced the incidence of meningococcal meningitis in China to historic lows. Worldwide, there has been a diversification of meningococcal serogroups, leading to a shift in dominant serogroups in China from serogroup A to serogroups C and B, accompanied by a rise in reports of serogroups Y and W.What is added by this report?:An outbreak of serogroup Y Neisseria meningitidis (Nm) in a secondary vocational school involved a single confirmed severe case and 24 individuals with laboratory-confirmed Nm carriage. Epidemiological investigation revealed that the outbreak was localized to the classroom of the confirmed case. Prolonged close contact within a confined space was identified as a significant risk factor for Nm transmission. The genotype sequence identified was type 1655 (ST-1655), which is categorized under clonal complex 23 (CC-23) and bears resemblance to 8 previously confirmed cases of serogroup Y meningococcal meningitis within Guangdong Province. This suggests that serogroup Y infections continue to sporadically emerge and have become prevalent strains.What are the implications for public health practice?:This outbreak underscores the critical need to enhance surveillance of meningococcal serogroups and population carrier, and advocate for vaccination with MenY-containing vaccines.

Background The strong invasiveness and rapid expansion of dengue virus (DENV) pose a great challenge to global public health. However, dengue epidemic patterns and mechanisms at a genetic scale, particularly in term of cross-border transmissions, remain poorly understood. Importation is considered as the primary driver of dengue outbreaks in China, and since 1990 a frequent occurrence of large outbreaks has been triggered by the imported cases and subsequently spread to the western and northern parts of China. Therefore, this study aims to systematically reveal the invasion and diffusion patterns of DENV-1 in Guangdong, China from 1990 to 2019.Methods These analyses were performed on 179 newly assembled genomes from indigenous dengue cases in Guangdong, China and 5152 E gene complete sequences recorded in Chinese mainland. The genetic population structure and epidemic patterns of DENV-1 circulating in Chinese mainland were characterized by phylogenetics, phylogeography, phylodynamics based on DENV-1 E-gene-based globally unified genotyping framework.Results Multiple serotypes of DENV were co-circulating in Chinese mainland, particularly in Guangdong and Yunnan provinces. A total of 189 transmission clusters in 38 clades belonging to 22 subgenotypes of genotype I, IV and V of DENV-1 were identified, with 7 Clades of Concern (COCs) responsible for the large outbreaks since 1990. The epidemic periodicity was inferred from the data to be approximately 3 years. Dengue transmission events mainly occurred from Great Mekong Subregion-China (GMS-China), Southeast Asia (SEA), South Asia Subcontinent (SASC), and Oceania (OCE) to coastal and land border cities respectively in southeastern and southwestern China. Specially, Guangzhou was found to be the most dominant receipting hub, where DENV-1 diffused to other cities within the province and even other parts of the country. Genome phylogeny combined with epidemiological investigation demonstrated a clear local consecutive transmission process of a 5C1 transmission cluster (5C1-CN4) of DENV-1 in Guangzhou from 2013 to 2015, while the two provinces of Guangdong and Yunnan played key roles in ongoing transition of dengue epidemic patterns. In contextualizing within Invasion Biology theories, we have proposed a derived three-stage model encompassing the stages of invasion, colonization, and dissemination, which is supposed to enhance our understanding of dengue spreading patterns.Conclusions This study demonstrates the invasion and diffusion process of DENV-1 in Chinese mainland within a global genotyping framework, characterizing the genetic diversities of viral populations, multiple sources of importation, and periodic dynamics of the epidemic. These findings highlight the potential ongoing transition trends from epidemic to endemic status offering a valuable insight into early warning, prevention and control of rapid spreading of dengue both in China and worldwide.

Background: In the past 10 years, the number of hand, foot, and mouth disease (HFMD) cases reported in Guangzhou, China,has averaged about 60,000 per year. It is necessary to conduct an in-depth analysis to understand the epidemiological patternand related influencing factors of HFMD in this region. Objective: This study aims to describe the epidemiological characteristics and spatiotemporal distribution of HFMD cases inGuangzhou from 2013 to 2022 and explore the relationship between sociodemographic factors and HFMD incidence. Methods: The data of HFMD cases in Guangzhou come from the Infectious Disease Information Management System of the Guangzhou Center for Disease Control and Prevention. Spatial analysis and space-time scan statistics were used to visualize the spatiotemporal distribution of HFMD cases. Multifactor ordinary minimum regression model, geographically weight ed regression, and geographically and temporally weighted regression were used to analyze the influencing factors, including population, economy, education, and medical care. Results: From 2013 to 2022, a total of 599,353 HFMD cases were reported in Guangzhou, with an average annual incidence rate of 403.62/100,000. Children aged 5 years and younger accounted for 93.64% (561,218/599,353) of all cases. HFMD cases showed obvious bimodal distribution characteristics, with the peak period from May to July and the secondary peakperiod from August to October. HFMDs in Guangzhou exhibited a spatial aggregation trend, with the central urban areashowing a pattern of low-low aggregation and the peripheral urban area demonstrating high-high aggregation. High-risk areasshowed a dynamic trend of shifting from the west to the east of peripheral urban areas, with coverage first increasing and thendecreasing. The geographically and temporally weighted regression model results indicated that population density (beta=-0.016)and average annual income of employees (beta=-0.007) were protective factors for HFMD incidence, while the average numberof students in each primary school (beta=1.416) and kindergarten (beta=0.412) was a risk factor. Conclusions: HFMD cases in Guangzhou were mainly infants and young children, and there were obvious differences in timeand space. HFMD is highly prevalent in summer and autumn, and peripheral urban areas were identified as high-risk areas.Improving the economic level of peripheral urban areas and reducing the number of students in preschool education institutionsare key strategies to controlling HFMD

Hand, foot and mouth disease (HFMD) is a common infectious disease in children, and caregivers’ awareness of the disease is key to reducing its incidence. This study aims to investigate the Knowledge, Attitude, and Practice (KAP) levels of caregivers in Guangzhou regarding HFMD and to analyze the association of their demographic characteristics and family situations. This cross-sectional study used face-to-face interviews with caregivers of infants and toddlers to assess their KAP status regarding HFMD through a structured questionnaire. The dependent variables were the scores for KAP, while independent variables included caregivers’ demographic characteristics, household size, etc. Univariate analysis was performed initially to identify potential predictors, and variables with a P-value ≤ 0.10 were included in the multivariate logistic regression model. Adjusted odds ratios and 95