Solid fuel use and low birth weight: a systematic review and meta-analysis.

Solid fuel use is increasingly linked to low birth weight (LBW), but conclusions were inconsistent. We aimed to summarize the association between solid fuel use and LBW. Twenty-one studies that met the inclusion criteria were identified through PubMed, Qvid Medline, and Web of Science databases. The final search occurred on March 20, 2024. Summary relative effect and 95 % confidence intervals were estimated with a random-effects model. Subgroup analyses and sensitivity analyses were performed to investigate possible sources of heterogeneity and to test the stability of the results. Nineteen studies evaluated the association between solid fuel use in pregnant woman and LBW (1.188 for solid fuels: 1.055 to 1.322). No significant heterogeneity was identified among the included studies (p=0.010, Tau2=0.02, I2=48.1 %). Subgroup analysis found positive correlations for Asia, data years prior to 2014, and rural studies (1.245 for Asia: 1.077 to 1.412; Tau2=0.03, I2=56.0 %; 1.243 for data years prior to 2014: 1.062 to 1.424; Tau2=0.04, I2=60.98 %; 1.514 for rural: 1.258 to 1.771; Tau2=0.00, I2=0.0 %). Our meta-analysis showed that solid fuel use in pregnant women had an impact on LBW. Measures and policies are also needed to promote energy conversion and to limit and reduce the use of solid fuels.

Seafarers' attitudes and chances to improve the nutrition on merchant ships from the crews' and cooks' perspective.

BACKGROUND: Seafarers' diets are often high in fat, sugar and calories, thus contributing to an increased risk of obesity, metabolic syndrome and cardiovascular disease. The multitude of obstacles to healthy eating in the on-board environment on merchant ships makes it essential to find new approaches for health promotion. This study explored seafarers' attitudes, the status quo of support measures and chances to improve nutrition on merchant ships from the perspective of crews and cooks. METHODS: In the course of the EU-funded project "e-healthy ship", European and Southeast Asian seafarers (N = 810) and ship cooks (N = 62) were examined by using two questionnaires on 68 ships of two German shipping companies. RESULTS: Almost all seafarers (98.8%) considered a healthy diet important for their well-being and the majority of seafarers reported being open-minded about changing their eating habits (88.4%). However, European seafarers were less likely to respond that they are willing to eat less meat [OR 0.11; 95%CI (0.07-0.17); p < .001], more vegetables [OR 0.10; 95%CI (0.02-0.49); p = .005] and more fruits [OR 0.11; 95%CI (0.02-0.61); p = .011] than their Southeast Asian colleagues. On the one hand, 82.3% of the ship cooks reported having taken part in at least one cooking course organized by their employer (1: 33.9%, 2: 25.8%, 3: 14.5%, 4 or more: 8.1%), on the other hand, slightly above half stated that the last of these courses had taken place more than 2 years ago. Furthermore, the ship cooks showed a positive attitude towards the use of a tablet-based digital platform that supports the ship cooks in daily and complex tasks (> 85% agreement). CONCLUSIONS: To improve nutrition on board merchant ships, various parameters need to be adjusted, such as ensuring a demand-oriented food supply on board or supporting seafarers' healthy food choices through target group-specific nutrition education. Ship cooks would be able to play a crucial role if they receive support. The development of a tablet-based digital platform that supports the ship cooks in their daily tasks, offers training and empowers them to implement health-promoting measures themselves seems to be an accepted and promising approach.

Mental well-being and sleep quality among vocational college students in Sichuan, China during standardized COVID-19 management measures.

Purpose: This research investigated the impact of the COVID-19 pandemic on the mental well-being and sleep quality of students in higher vocational colleges in Sichuan, China, identifying key factors influencing their psychological health during this period. Methods: Between January and February 2022, a comprehensive survey was conducted among students from several higher vocational colleges in Sichuan, utilizing a randomized selection approach to involve 3,300 participants. Data were collected through direct interviews executed by skilled interviewers. Results: Out of 3,049 valid responses, a significant number reported experiencing symptoms of poor mental health, anxiety, depression, and insomnia, with prevalence rates of 21.2%, 9.7%, 14.1%, and 81.9%, respectively. Factors contributing positively to mental health and sleep included a higher family economic status, reduced stress from the pandemic, and decreased online activity. Conversely, lack of physical activity post-pandemic, disruptions to education and employment, and deteriorating relationships emerged as negative influencers. Interestingly, a lack of pre-pandemic mental health knowledge acted as a protective factor against insomnia. Conclusion: The ongoing management of COVID-19 has notably influenced the psychological and sleep health of vocational college students, driven by economic, emotional, lifestyle, and educational factors. The findings underscore the necessity for targeted interventions to address these challenges effectively.

Analysis of a large SARS-CoV-2 (Alpha) outbreak in a Catalan prison using conventional and genomic epidemiology.

Enforcing strict protocols that prevent transmission of airborne infections in prisons is challenging. We examine a large SARS-CoV-2 outbreak in a Catalan penitentiary center from February-March 2021, prior to vaccination deployment. The aim was to describe the evolution of the outbreak using classical and genomic epidemiology and the containment strategy applied. The outbreak was initially detected in one module but spread to four, infecting 7 staff members and 140 incarcerated individuals, 6 of whom were hospitalized (4.4%). Genomic analysis confirmed a single origin (B.1.1.7). Contact tracing identified transmission vectors between modules and prevented further viral spread. In future similar scenarios, the control strategy described here may help limiting transmission of airborne infections in correctional settings.

Evaluation of intervention measures in reducing the driver's exposure to respiratory particles in a taxi with infected passengers.

In the fifth wave of the COVID-19 epidemic in Hong Kong in early 2022, the large number of infected persons caused a shortage of ambulances and transportation vehicles operated by the government. To solve the problem, taxi drivers were recruited to transport infected persons to hospitals in their taxis. However, many of the drivers were infected after they began to participate in the plan. To tackle this issue, the present study numerically evaluated the effectiveness of several intervention measures in reducing the infection risk for taxi drivers. First, experiments were conducted inside a car to validate the large-eddy simulation (LES)-Lagrangian model for simulation of particle transport in a car. The validated model was then applied to calculate the particle dispersion and deposition in a Hong Kong taxi with intervention measures that included opening windows, installing partitions, and using a far-UVC lamp. The results show that opening the windows can significantly reduce the driver's total exposure by 97.4 %. Installing partitions and using a far-UVC lamp can further reduce the infection risk of driver by 55.9 % and 32.1 %, respectively. The results of this study can be used to support the implementation of effective intervention measures to protect taxi drivers from infection.

Do government intervention measures promote e-waste recycling in China?

To improve the low e-waste recycling rate, the Chinese government has introduced a series of intervention measures. However, the effectiveness of government intervention measures is controversial. This paper constructs a system dynamics model to study the impact of Chinese government intervention measures on e-waste recycling from a holistic perspective. Our results demonstrate that the current Chinese government intervention measures do not promote e-waste recycling. By studying the adjustment strategies of government intervention measures, it can be found that the most effective adjustment strategy is to increase government policy support while increasing the punishments for recyclers. If the government only adjusts a kind of intervention measures, it is better to increase punishments than to increase incentives. And increasing the punishment for recyclers is more effective than increasing the punishment for collectors. If the government chooses to increase incentives, then the government should only increase policy support. This is because increasing the subsidy support is ineffective.

The city-wide full-scale interactive application of sewage surveillance programme for assisting real-time COVID-19 pandemic control - A case study in Hong Kong.

The paper discusses the implementation of Hong Kong's tailor-made sewage surveillance programme led by the Government, which has demonstrated how an efficient and well-organized sewage surveillance system can complement conventional epidemiological surveillance to facilitate the planning of intervention strategies and actions for combating COVID-19 pandemic in real-time. This included the setting up of a comprehensive sewerage network-based SARS-CoV-2 virus surveillance programme with 154 stationary sites covering 6 million people (or 80 % of the total population), and employing an intensive monitoring programme to take samples from each stationary site every 2 days. From 1 January to 22 May 2022, the daily confirmed case count started with 17 cases per day on 1 January to a maximum of 76,991 cases on 3 March and dropped to 237 cases on 22 May. During this period, a total of 270 "Restriction-Testing Declaration" (RTD) operations at high-risk residential areas were conducted based on the sewage virus testing results, where over 26,500 confirmed cases were detected with a majority being asymptomatic. In addition, Compulsory Testing Notices (CTN) were issued to residents, and the distribution of Rapid Antigen Test kits was adopted as alternatives to RTD operations in areas of moderate risk. These measures formulated a tiered and cost-effective approach to combat the disease in the local setting. Some ongoing and future enhancement efforts to improve efficacy are discussed from the perspective of wastewater-based epidemiology. Forecast models on case counts based on sewage virus testing results were also developed with R2 of 0.9669-0.9775, which estimated that up to 22 May 2022, around 2,000,000 people (~67 % higher than the total number of 1,200,000 reported to the health authority, due to various constraints or limitations) had potentially contracted the disease, which is believed to be reflecting the real situation occurring in a highly urbanized metropolis like Hong Kong.

Investigating the trend of road traffic fatalities in Malawi using Mann-Kendall statistic.

Fatalities due to road accidents remain a major challenge worldwide. In the recent years, Malawi, one of the developing African countries with a total population of about 19 million has also been witnessing a very high fatality rate [of about 31 crash deaths per 100,000 population in 2016] compared to most of its neighbours in the region. This seems to be continuously increasing even with several intervention measures, such as, speed and alcohol impairment laws, and laws for mandatory seatbelt and helmet use. In view of this, the study attempted to investigate the trend of road fatalities in Malawi, such that effectiveness of the existing measures can be established. For this, archived crash data of road fatalities between years 2000-2021 were used to undertake intervention and trend analyses. The method of Cumulative Summation was used to identify intervention points in the series, followed by the Mann-Kendall statistic (τ) to determine the trend during the intervened period using the non-parametric Rank-Sum test to support the findings. The results showed that the trend has been decreasing in the early years of legislating policy measures [2000-2012] and, thereafter [2013-2021], increased significantly [τ = 0.8333]. This suggests that there was acceptance of the measures by the motorists/public in the early years of implementation [2000-2012], which might have been overshadowed by vehicle population growth and weak enforcement mechanism that have seen the trend increasing lately. The study therefore suggests that there is still a scope to review the intervention measures in their effective implementation as well as regular monitoring.

Achieving Carbon Neutrality through Urban Planning and Design.

Much of the research on climate change has focused on carbon reduction in cities or countries. However, more attention needs to be paid to how to achieve carbon neutrality in the urban design and planning stage, and the lack of quantitative analysis of carbon related to urban space makes it difficult to locate urban space and provide direct guidance for urban planning and design. This study proposed three optimization paths to achieve carbon neutrality in multi-scale urban building clusters. Firstly, we reconstructed the quantitative calculation system of urban building communities with the goal of carbon neutrality; secondly, we screened the carbon source reduction and carbon sink interventions that are suitable for multi-scale urban building communities; finally, we constructed a carbon emission and carbon sink calculation system of planning and design schemes based on the layout of relevant elements of planning and design schemes with a grid cell of 100 × 100 m. In practice, there was a gap of about 115,000 tons of CO2 from the carbon-neutral target and 26% of carbon emission was distributed in the Xiajiabian Station TOD. In this study, nine types of carbon reduction measures were adopted to achieve carbon neutrality in the region, among which the highest carbon reduction was achieved by biomass energy measures, accounting for 29% of the total carbon reduction of 33,745.27 T. The objective of this study is to accurately and quantitatively assess the carbon targets of urban spaces at different scales and adopt effective measures to achieve carbon neutrality.

Improved indoor air quality during desert dust storms: The impact of the MEDEA exposure-reduction strategies.

Desert dust storms (DDS) are natural events that impact not only populations close to the emission sources but also populations many kilometers away. Countries located across the main dust sources, including countries in the Eastern Mediterranean, are highly affected by DDS. In addition, climate change is expanding arid areas exacerbating DDS events. Currently, there are no intervention measures with proven, quantified exposure reduction to desert dust particles. As part of the wider "MEDEA" project, co-funded by LIFE 2016 Programme, we examined the effectiveness of an indoor exposure-reduction intervention (i.e., decrease home ventilation during DDS events and continuous use of air purifier during DDS and non-DDS days) across homes and/or classrooms of schoolchildren with asthma and adults with atrial fibrillation in Cyprus and Crete-Greece. Participants were randomized to a control or intervention groups, including an indoor intervention group with exposure reduction measures and the use of air purifiers. Particle sampling, PM10 and PM2.5, was conducted in participants' homes and/or classrooms, between 2019 and 2022, during DDS-free weeks and during DDS days for as long as the event lasted. In indoor and outdoor PM10 and PM2.5 samples, mass and content in main and trace elements was determined. Indoor PM2.5 and PM10 mass concentrations, adjusting for premise type and dust conditions, were significantly lower in the indoor intervention group compared to the control group (PM2.5-intervention/PM2.5-control = 0.57, 95% CI: 0.47, 0.70; PM10-intervention/PM10-control = 0.59, 95% CI: 0.49, 0.71). In addition, the PM2.5 and PM10 particles of outdoor origin were significantly lower in the intervention vs. the control group (PM2.5 infiltration intervention-to-control ratio: 0.49, 95% CI: 0.42, 0.58; PM10 infiltration intervention-to-control ratio: 0.68, 95% CI: 0.52, 0.89). Our findings suggest that the use of air purifiers alongside decreased ventilation measures is an effective protective measure that reduces significantly indoor exposure to particles during DDS and non-DDS in high-risk population groups.

[Nursing research progress of stigma for patients with benign prostatic hyperplasia].

Benign prostatic hyperplasia (BPH) commonly occurs in middle-aged and elderly men, affecting their physical health while also triggering varying degrees of stigma. This leads to reduced treatment compliance and a lower quality of life for patients. This article elaborates on the conceptual development of stigma, the current state of stigma in BPH patients, sources and impacts of stigma, tools for investigating stigma, and intervention measures. The aim is to enhance medical professionals' understanding of stigma and provide a basis for effective nursing interventions.

Spatial-temporal clustering of an outbreak of SARS-CoV-2 Delta VOC in Guangzhou, China in 2021.

Background: In May 2021, the SARS-CoV-2 Delta variant led to the first local outbreak in China in Guangzhou City. We explored the epidemiological characteristics and spatial-temporal clustering of this outbreak. Methods: Based on the 153 cases in the SARS-CoV-2 Delta variant outbreak, the Knox test was used to analyze the spatial-temporal clustering of the outbreak. We further explored the spatial-temporal clustering by gender and age groups, as well as compared the changes of clustering strength (S) value between the two outbreaks in Guangzhou. Results: The result of the Knox analysis showed that the areas at short distances and brief periods presented a relatively high risk. The strength of clustering of male-male pairs was higher. Age groups showed that clustering was concentrated in cases aged ≤ 18 years matched to 18-59 years and cases aged 60+ years. The strength of clustering of the outbreak declined after the implementation of public health measures. The change of strength of clustering at time intervals of 1-5 days decreased greater in 2021 (S = 129.19, change rate 38.87%) than that in 2020 (S = 83.81, change rate 30.02%). Conclusions: The outbreak of SARS-CoV-2 Delta VOC in Guangzhou has obvious spatial-temporal clustering. The timely intervention measures are essential role to contain this outbreak of high transmission.

Utility of Scoring System for Screening and Early Warning of Cervical Cancer Based on Big Data Analysis.

Objective: To explore the utility of the scoring system for screening and early warning of cervical cancer based on big data analysis. Methods: A total of 420 women undergoing physical examination in Shenyang from January 2021 to January 2022 were screened by convenient sampling as the study subjects. All females accepted the human papilloma virus (HPV) tests and thin-prep cytology test (TCT), a Rating Questionnaire for Screening and Early Warning of Cervical Cancer was developed, and a warning threshold was derived according to the scores of the questionnaire and the goodness of fit for the results of HPV+TCT tests. The patients were graded according to the threshold, and corresponding intervention strategies for patients of different grades were developed. Results: Among the 420 people undergoing physical examination, 92 (21.90%) obtained scores ≥8 points, and 328 (78.10%) obtained scores < 8 points; in diagnosing cervical cancer, the Rating Questionnaire for Screening and Early Warning of Cervical Cancer had an AUC value of 0.848, specificity of 97.22%, and sensitivity of 86.46%; after scientific intervention, HPV test results showed a significant decrease in both high-risk positive cases and low-risk positive cases (p < 0.05), and TCT results showed that there was a significant difference in the number of patients with CIN I before and after intervention (p < 0.05). Conclusion: The scoring system for screening and early warning of cervical cancer based on big data analysis presents certain clinical value in the clinical screening of cervical cancer, which can further improve the screening coverage, is of great significance for the diagnosis and treatment of disease, and helps physician implement hierarchical diagnosis and treatment quickly and precisely.

China's Fight Against COVID-19: What We Have Done and What We Should Do Next?

Background: Chinese government conducted unprecedented massive public health prevention interventions at the national level, which have effectively contained the spread of Coronavirus Disease 2019 (COVID-19) infections. Specifically, the outbreak in Wuhan has been effectively controlled. Meanwhile, the Chinese efforts to contain the virus have been widely recognized. Even the World Health Organization has praised the efforts of the Chinese government and advised other countries to learn from China's experience in the fight against COVID-19. However, the measures that have been conducted by China to effectively prevent the spread of COVID 19 in the country have not been rigorously analyzed. Therefore, this study aimed to explore the characteristics of China's control and prevention strategies, and identify the elements that changed the epidemiological curve of rapidly rising new confirmed cases of COVID-19. Methods: Public health intervention measures and their effects on the spread of COVID-19 in terms of daily newly confirmed and cumulative cases were collected between January 20, 2020, and March 5. Notices of the Joint Prevention and Control Mechanism for COVID-19 of the State Council on Implementing Measures in Hubei were collected. Information obtained by relevant important documents and announcements was collected from the official website of the Chinese government. Additionally, from other media platforms, news, articles, and reviews were used to explain the intervention measure. Thus, using these data, we performed a retrospective description of the intervention strategies at three stages. Results: The Chinese government adopted non-pharmacological interventions measures (NPIs) timely and efficiently. On February 20, the declining epidemic trend in China indicated that the three strictest disease prevention and control strategies issued by the Hubei Government had contributed to a smooth decline in the spread of the epidemic. Conclusions: The NPIs taken by China play a decisive role to control the spread of novel coronavirus outbreaks. Further research and action are needed to ensure a sufficiently sensitive surveillance system and strong response mechanism, including the establishment of a highly accessible laboratory network, maintenance of awareness of both primary healthcare providers and the public, and regular training and exercise of local Centers for Disease Control and Prevention and general practitioners in the community-level.

Combinational Recommendation of Vaccinations, Mask-Wearing, and Home-Quarantine to Control Influenza in Megacities: An Agent-Based Modeling Study With Large-Scale Trajectory Data.

The outbreak of COVID-19 stimulated a new round of discussion on how to deal with respiratory infectious diseases. Influenza viruses have led to several pandemics worldwide. The spatiotemporal characteristics of influenza transmission in modern cities, especially megacities, are not well-known, which increases the difficulty of influenza prevention and control for populous urban areas. For a long time, influenza prevention and control measures have focused on vaccination of the elderly and children, and school closure. Since the outbreak of COVID-19, the public's awareness of measures such as vaccinations, mask-wearing, and home-quarantine has generally increased in some regions of the world. To control the influenza epidemic and reduce the proportion of infected people with high mortality, the combination of these three measures needs quantitative evaluation based on the spatiotemporal transmission characteristics of influenza in megacities. Given that the agent-based model with both demographic attributes and fine-grained mobility is a key planning tool in deploying intervention strategies, this study proposes a spatially explicit agent-based influenza model for assessing and recommending the combinations of influenza control measures. This study considers Shenzhen city, China as the research area. First, a spatially explicit agent-based influenza transmission model was developed by integrating large-scale individual trajectory data and human response behavior. Then, the model was evaluated across multiple intra-urban spatial scales based on confirmed influenza cases. Finally, the model was used to evaluate the combined effects of the three interventions (V: vaccinations, M: mask-wearing, and Q: home-quarantining) under different compliance rates, and their optimal combinations for given control objectives were recommended. This study reveals that adults were a high-risk population with a low reporting rate, and children formed the lowest infected proportion and had the highest reporting rate in Shenzhen. In addition, this study systematically recommended different combinations of vaccinations, mask-wearing, and home-quarantine with different compliance rates for different control objectives to deal with the influenza epidemic. For example, the "V45%-M60%-Q20%" strategy can maintain the infection percentage below 5%, while the "V20%-M60%-Q20%" strategy can maintain the infection percentage below 15%. The model and policy recommendations from this study provide a tool and intervention reference for influenza epidemic management in the post-COVID-19 era.

Modeling the Impact of Management Changes on the Infection Dynamics of Extended-Spectrum Beta-Lactamase-Producing Escherichia coli in the Broiler Production.

Livestock animals, especially poultry, are a known reservoir for extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (E. coli). They may enter the pen either via positive day-old chicks or via the environment. We developed a mathematical model to illustrate the entry and dissemination of resistant bacteria in a broiler pen during one fattening period in order to investigate the effectiveness of intervention measures on this infection process. Different management measures, such as varying amounts of litter, a slow-growing breed or lower stocking densities, were tested for their effects on broiler colonization. We also calculated the impact of products that may influence the microbiota in the chicks' digestive tract, such as pre- or probiotics, feed supplements or competitive exclusion products. Our model outcomes show that a contaminated pen or positive chicks at the beginning of the fattening period can infect the entire flock. Increasing the amount of litter and decreasing the stocking density were shown to be effective in our model. Differences in the route of entry were found: if the chicks are already positive, the litter quantity must be increased to at least six times the standard of 1000 g/m2, whereas, if the pen is contaminated on the first day, three times the litter quantity is sufficient. A reduced stocking density of 20 kg/m2 had a significant effect on the incidence of infection only in a previously contaminated pen. Combinations of two or three measures were effective in both scenarios; similarly, feed additives may be beneficial in reducing the growth rate of ESBL-producing E. coli. This model is a valuable tool for evaluating interventions to reduce the transmission and spread of resistant bacteria in broiler houses. However, data are still needed to optimize the model, such as growth rates or survival data of ESBL-producing E. coli in different environments.

[Strategies for the rational use of antibiotics in the outpatient sector-results of a workshop with key stakeholders in the healthcare system]. / Strategien zum rationalen Antibiotikaeinsatz im ambulanten Sektor ­ Ergebnisse eines Workshops mit wichtigen Akteuren des Gesundheitswesens.

In November 2021, the Federal Ministry of Health (BMG) organized the one-day virtual workshop "Rational antibiotic use in the outpatient sector - potential and opportunities for change" with scientific support from the Robert Koch Institute (RKI). The aim was to collect strategies for promoting the appropriate use of antibiotics in the outpatient sector. With 114 participants, important stakeholders of the healthcare system were represented. In the run-up to the event, the invited participants had already been asked to take part in an online survey on perspectives, experiences, and ideas for the rational use of antibiotics in the outpatient sector. The answers were analyzed and presented at the workshop.The workshop was introduced with plenary lectures on the German Antibiotic Resistance Strategy (DART) and the antibiotic resistance situation in Germany. All experts participated in 10 working group discussions; the resulting findings were presented in the concluding plenary session. In this conference report, selected aspects of these discussions are presented. The insights gained are to be incorporated into the "DART 2030" strategy.

COVID-19 public health measures reduce the incidence of respiratory infectious diseases.

BACKGROUND: Children and the elderly are two special subpopulations for coronavirus disease 2019 (COVID-19) and respiratory tract infections (RTIs). The study aimed to evaluate the effect of COVID-19 public health measures on the burden of RTIs in China by performing a two-center investigation. METHODS: The electronic medical records of all inpatients in departments of pediatrics and respiratory medicine of Taizhou Fourth People's Hospital (Taizhou, China) and Shaanxi Provincial People's Hospital (Xi'an, China) during January 1, 2019 to June 30, 2021 were analyzed. A total of 18,084 child inpatients and 14,802 adult inpatients were included. RESULTS: The vast majority (88.3%-90.6%) of the adult inpatients were the elderly, aged over 50 years. The numbers of child and adult (elderly) inpatients, and the proportions of RTI-associated diseases substantially decreased during COVID-19 pandemic (2020-2021) compared to that before the pandemic (2019) in Taizhou and Xi'an. A significantly higher proportion of LRTI-associated diseases was observed in elderly female inpatients (53.4-55.6%) than elderly male inpatients (34.3-41.5%) (p < 0.001) in spite of more male inpatients than female inpatients (1.94-1.95:1). CONCLUSIONS: COVID-19-related interventions provide an additional beneficial effect on reduction of RTI-associated diseases in both children and the elderly.

Risk assessment for precise intervention of COVID-19 epidemic based on available big data and spatio-temporal simulation method: Empirical evidence from different public places in Guangzhou, China.

Risk assessment of the intra-city spatio-temporal spreading of COVID-19 is important for providing location-based precise intervention measures, especially when the epidemic occurred in the densely populated and high mobile public places. The individual-based simulation has been proven to be an effective method for the risk assessment. However, the acquisition of individual-level mobility data is limited. This study used publicly available datasets to approximate dynamic intra-city travel flows by a spatio-temporal gravity model. On this basis, an individual-based epidemic model integrating agent-based model with the susceptible-exposed-infectious-removed (SEIR) model was proposed and the intra-city spatio-temporal spreading process of COVID-19 in eleven public places in Guangzhou China were explored. The results indicated that the accuracy of dynamic intra-city travel flows estimated by available big data and gravity model is acceptable. The spatio-temporal simulation method well presented the process of COVID-19 epidemic. Four kinds of spatial-temporal transmission patterns were identified and the pattern was highly dependent on the urban spatial structure and location. It indicated that location-based precise intervention measures should be implemented according to different regions. The approach of this research can be used by policy-makers to make rapid and accurate risk assessments and to implement intervention measures ahead of epidemic outbreaks.