Epidemic Control Research Articles

Difference in Rumor Dissemination and Debunking Before and After the Relaxation of COVID-19 Prevention and Control Measures in China: Infodemiology Study.

The information epidemic emerged along with the COVID-19 pandemic. While controlling the spread of COVID-19, the secondary harm of epidemic rumors to social order cannot be ignored. The objective of this paper was to understand the characteristics of rumor dissemination before and after the pandemic and the corresponding rumor management and debunking mechanisms. This study aimed to provide a theoretical basis and effective methods for relevant departments to establish a sound mechanism for managing network rumors related to public health emergencies such as COVID-19. This study collected data sets of epidemic rumors before and after the relaxation of the epidemic prevention and control measures, focusing on large-scale network rumors. Starting from 3 dimensions of rumor content construction, rumor propagation, and rumor-refuting response, the epidemic rumors were subdivided into 7 categories, namely, involved subjects, communication content, emotional expression, communication channels, communication forms, rumor-refuting subjects, and verification sources. Based on this framework, content coding and statistical analysis of epidemic rumors were carried out. The study found that the rumor information was primarily directed at a clear target audience. The main themes of rumor dissemination were related to the public's immediate interests in the COVID-19 field, with significant differences in emotional expression and mostly negative emotions. Rumors mostly spread through social media interactions, community dissemination, and circle dissemination, with text content as the main form, but they lack factual evidence. The preferences of debunking subjects showed differences, and the frequent occurrence of rumors reflected the unsmooth channels of debunking. The χ2 test of data before and after the pandemic showed that the P value was less than .05, indicating that the difference in rumor content before and after the pandemic had statistical significance. This study's results showed that the themes of rumors during the pandemic are closely related to the immediate interests of the public, and the emotions of the public accelerate the spread of these rumors, which are mostly disseminated through social networks. Therefore, to more effectively prevent and control the spread of rumors during the pandemic and to enhance the capability to respond to public health crises, relevant authorities should strengthen communication with the public, conduct emotional risk assessments, and establish a joint mechanism for debunking rumors.

Optimization of N fertilizer and synergistic intercropping to enhance the productivity advantage of faba bean and effective control of chocolate spot epidemics.

Intercropping of wheat/faba bean is a common practice within the legume-cereal family. However, the benefits of nitrogen (N) fertilizer optimized synergistic intercropping in improving faba bean productivity while controlling the prevalence of chocolate spot disease have not been established. This study conducted continuous field experiments spanning two planting seasons to investigate two key findings. (1) Optimizing N fertilizer application can enhance the productivity of intercropped faba bean. (2) The percentage severity index (PSI) during the period of maximum prevalence rate (Rmax) of faba bean chocolate spot disease, poses a substantial challenge to faba bean yield. The results indicated that the land equivalent ratio and transgressive overyielding index for each intercropping treatment increased with higher N fertilizer application, exceeding a value of 1, and the land saving proportion also exceeded 0. Intercropping primarily enhances productivity, as measured by the harvest index (HI), by amplifying the complementary effect rather than the selection effect, thus improving the net benefit of intercropping. The HI of single and intercropped faba bean increased with the N1 and N2 treatments in both planting seasons. However, the HI of single and intercropped faba bean at the N3 level decreased significantly, ranging from 17.85% to 29.62%. Furthermore, a notable negative correlation was established between the PSI during critical epidemic (initial epidemic, maximum epidemic rate, and late epidemic) periods and observed and expected faba bean yields. As PSI increased, faba bean yields decreased and PSI of intercropping at different periods were lower than those observed in the single cropping. Additionally, intercropping with the optimized N fertilizer treatment (N2 treatment) exhibited an enhanced relative control effect on chocolate spot disease in faba bean, ranging from 35.21% to 52.36%. This finding confirmed the productivity advantage of intercropping faba bean. In conclusion, this study suggested that optimizing N fertilizer application can enhance the productivity of intercropped faba bean. Wheat/faba bean intercropping effectively controlled the PSI during the period of Rmax, which would otherwise threaten faba bean yield. Consequently, this practice ensured sustained advantages of wheat/faba bean intercropping.

Optimal Control for an Epidemic Model of COVID-19 with Time-Varying Parameters

The coronavirus disease 2019 (COVID-19) pandemic disrupted public health and economies worldwide. In this paper, we investigate an optimal control problem to simultaneously minimize the epidemic size and control costs associated with intervention strategies based on official data. Considering people with undetected infections, we establish a control system of COVID-19 with time-varying parameters. To estimate these parameters, a parameter identification scheme is adopted and a mixed algorithm is constructed. Moreover, we present an optimal control problem with two objectives that involve the newly increased number of infected individuals and the control costs. A numerical scheme is conducted, simulating the epidemic data pertaining to Shanghai during the period of 2022, caused by the Omicron variant. Coefficient combinations of the objectives are obtained, and the optimal control measures for different infection peaks are indicated. The numerical results suggest that the identification variables obtained by using the constructed mixed algorithm to solve the parameter identification problem are feasible. Optimal control measures for different epidemic peaks can serve as references for decision-makers.

Construction and reflections on the disease prevention and control system of aquatic organisms based on management perspective

Construction and reflections on the disease prevention and control system of aquatic organisms based on management perspective

Viral invasion, incubation, and outbreak under the normalized operation of urban systems: a spatial cognition-driven transmission model of infectious diseases

ABSTRACT Large-scale epidemics, such as COVID-19, pose significant threats to human health and social stability due to their rapid and covert transmission, emerging as one of the main challenges to maintaining a well-functioning urban system. During the pandemic, the spatial transmission mechanisms and their influencing factors of infectious diseases have received as a central topic. Scholars concentrated on researching the phase of extensive dissemination and mandatory intervention, utilizing multiple datasets. However, there remains a notable gap in the investigation of virus spatial transmission mechanisms under normalized urban operations due to limitations in detection timeliness and data collection issues. Moreover, compared to various intervention strategies, the influence of human behavioral dynamics and spatial cognition remains understudied. The paper simulates invasion, incubation, and outbreak of the Omicron variant in Zhuhai City in 2022, validating the results against real-world epidemic data. By comparing spatial diffusion patterns under three levels of spatial cognition, it sheds light on the delayed impact of human spatial cognitive abilities on urban pandemic outbreaks and their influence on virus invasion orders. The simulation model and revealed diffusion mechanisms will provide important guidance for the proactive prevention and control of unpredictable large-scale epidemics in future urban systems.

A multilevel analysis of the determinants of HIV testing among men in Sub-Saharan Africa: Evidence from Demographic and Health Surveys across 10 African countries.

Sub-Saharan Africa, the epicenter of the HIV epidemic, has seen significant reductions in new infections over the last decade. Although most new infections have been reported among women, particularly adolescent girls, men are still disadvantaged in accessing HIV testing, care, and treatment services. Globally, men have relatively poorer HIV testing, care, and treatment indices when compared with women. Gender norms and the associated concept of masculinity, strength, and stereotypes have been highlighted as hindering men's acceptance of HIV counseling and testing. Therefore, men's suboptimal uptake of HIV testing services will continue limiting efforts to achieve HIV epidemic control. Thus, this study aimed to identify individual, neighborhood, and country-level determinants of sub-optimal HIV testing among men in Sub-Saharan African countries. We analyzed demographic and health datasets from surveys conducted between 2016 and 2020 in Sub-Saharan African Countries. We conducted multivariable multilevel regression analysis on 52,641 men aged 15-49 years resident in 4,587 clusters across 10 countries. The primary outcome variable was ever tested for HIV. HIV testing services uptake among men in these ten Sub-Saharan African countries was 35.1%, with a high of 65.5% in Rwanda to a low of 10.2% in Guinea. HIV testing services uptake was more likely in men with increasing age, some form of formal education, in employment, ever married, and residents in relatively wealthier households. We also found that men who possessed health insurance, had some form of weekly media exposure, and had accessed the internet were more likely to have ever received an HIV test. Unlike those noted to be less likely to have ever received an HIV test if they had discriminatory attitudes towards HIV, comprehensive HIV knowledge, recent sexual activity, and risky sexual behavior were positive predictors of HIV testing services uptake among men. Furthermore, men in communities with high rurality and illiteracy were less likely to receive an HIV test. Individual and community-level factors influence the uptake of HIV testing among Sub-Saharan African men. There was evidence of geographical clustering in HIV testing uptake among men at the community level, with about two-thirds of the variability attributable to community-level factors. Therefore, HIV testing programs will need to design interventions that ensure equal access to HIV testing services informed by neighborhood socioeconomic conditions, peculiarities, and contexts.

A dynamics model of the emergency medical supply chain in epidemic considering deprivation cost

Emergency medical supplies are the basic resources for epidemic prevention and reducing disaster losses. If the supplies cannot be provided in time, the victims will suffer psychological or physical pain. This paper uses the deprivation cost (DC) to measure the victims’ suffering in COVID-19 cases. After analyzing the dynamic relationship between epidemic control and supplies providing, a system dynamics (SD) model of emergency medical supply chain considering the deprivation cost is proposed. Furthermore, based on the case of epidemic prevention in Wuhan, China, in early 2020, we explore the influence of the strength of the mobilization policy (SMP), concerns about data reliability (CDR), and public confidence in emergency response (PCER) on the operation of the supply chain, by which the effective strategies can be found to improve the efficiency of emergency supplies support. The results show that: at the late stage of epidemic control, concerns about data reliability will inhibit the growth of the demand fulfillment rate (DFR), while enhancing the strength of the mobilization policy can appropriately improve the demand fulfillment rate. Restoring public confidence in emergency response can delay personnel panic and contribute to epidemic control, but it has no significant effect on demand fulfillment rate and deprivation cost.

The Impact of Coping Styles on the Mental Health of Outstanding Physical Education Students in Shanghai During the Normalization Epidemic: The Chain Mediation Role of Meaning in Life and Prosocial Behavior.

The continuous spread of the epidemic has inflicted serious harm upon individual's mental well-being, and effective coping mechanisms are associated with positive mental health outcomes. Prosocial behavior and a sense of meaning in life can enhance individuals' subjective well-being, which can subsequently positively impact their mental health. Thus, in the context of epidemic prevention and control, this study investigates the relationship between the meaning in life, prosocial behavior, and coping styles of outstanding physical education students and the impact on their mental health. The study involved a questionnaire survey on 498 outstanding physical education students, consisting of 297 boys (mean age = 13.16) and 201 girls (mean age = 12.87 years). Subsequently, the data was analyzed using the mediating effect and Bootstrap tests. The coping style positively predicted the meaning in life (β=0.294) and prosocial behavior (β=0.293). Conversely, mental health was predicted in a negative direction (β=-0.494). Mental health negatively predicted prosocial behavior (β=-0.810), although prosocial behavior positively predicted meaning in life (β=0.644). Finally, prosocial behavior negatively predicted mental health (β=-0.513). Additionally, the interplay between prosocial behavior and meaning in life is established in terms of both the individual and chain mediating roles. This study demonstrates that coping styles during a normalized epidemic prevention and control situation directly impact the mental health of Shanghai's outstanding physical education students. Additionally, these coping styles indirectly influence mental health through the mediating effects of meaning in life and prosocial behaviors. Furthermore, meaning in life and prosocial behaviors act as chain mediators in this relationship.

What we learned from the COVID-19 infection control and what we need in the future, a quantitative and qualitative study on hospital infection prevention and control practitioners (HIPCPs) in Tianjin, China

BackgroundIn December 2022, the epidemic prevention and control policy was upgraded and China came to a different stage of epidemic control. There have been no studies from the perspective of infection prevention and control practitioners (HIPCP) about the historic surge. ObjectiveTo understand the needs of the healthcare system during the epidemic and to identify implications for better healthcare supply and infection control in the future. MethodsA longitudinal quantitative and qualitative study was performed based on two comprehensive questionnaire surveys among 497 HIPCPs before and during the epidemic peak in Tianjin, China. ResultsThe workload (8.2 hours vs 10.14 hours, P = 0) and self-reported mental health problems (23.5% vs. 61.8%, P < 0.05) among the HIPCPs increased significantly in the peak period. Ward reconstruction and resource coordination were the most needed jobs in hospital infection control, and rapidly increased medical waste during the epidemic needs to be considered in advance. Community support for healthcare personnel and their families, maintaining full PPE to reduce simultaneous infection of medical staff, and clinical training of infectious diseases for medical staff, especially doctors in advance are the most important things we learned. ConclusionAlthough it has been four years since the first outbreak of COVID-19, more improvements should be made to prepare for the next wave of COVID-19 or other diseases.

Contagion dynamics in time-varying metapopulation networks with node's activity and attractiveness.

The metapopulation network model is a mathematical framework used to study the spatial spread of epidemics with individuals' mobility. In this paper, we develop a time-varying network model in which the activity of a population is correlated with its attractiveness in mobility. By studying the spreading dynamics of the SIR (susceptible-infectious-recovered)-type disease in different correlated networks based on the proposed model, we theoretically derive the mobility threshold and numerically observe that increasing the correction between activity and attractiveness results in a reduced mobility threshold but suppresses the fraction of infected subpopulations. It also introduces greater heterogeneity in the spatial distribution of infected individuals. Additionally, we investigate the impact of nonpharmaceutical interventions on the spread of epidemics in different correlation networks. Our results show that the simultaneous implementation of self-isolation and self-protection is more effective in negatively correlated networks than that in positively correlated or non-correlated networks. Both self-isolation and self-protection strategies enhance the mobility threshold and, thus, slow down the spread of the epidemic. However, the effectiveness of each strategy in reducing the fraction of infected subpopulations varies in different correlated networks. Self-protection is more effective in positively correlated networks, whereas self-isolation is more effective in negatively correlated networks. Our study will provide insights into epidemic prevention and control in large-scale time-varying metapopulation networks.

IMVis: Visual analytics for influence maximization algorithm evaluation in hypergraphs

Influence maximization (IM) algorithms play a significant role in hypergraph analysis tasks, such as epidemic control analysis, viral marketing, and social influence analysis, and various IM algorithms have been proposed. The main challenge lies in IM algorithm evaluation, due to the complexity and diversity of spreading processes of different IM algorithms in different hypergraphs. Existing evaluation methods mainly leverage statistical metrics, such as influence spread, to quantify overall performance, but do not fully unravel spreading characteristics and patterns. In this paper, we propose an exploratory visual analytics system, IMVis, to assist users in exploring and evaluating IM algorithms at the overview, pattern, and node levels. A spreading pattern mining method is first proposed to characterize spreading processes and extract important spreading patterns to facilitate efficient analysis and comparison of IM algorithms. Novel visualization glyphs are designed to comprehensively reveal both temporal and structural features of IM algorithms’ spreading processes in hypergraphs at multiple levels. The effectiveness and usefulness of IMVis are demonstrated through two case studies and expert interviews.

Study on the regulatory alienation effect of China's Environmental Protection Tax Law during the strict epidemic control period: based on a sample test of 1000 tax personnel

The enactment of the Environmental Protection Tax Law was a major event in the process of China's economic and social development. This law has achieved certain results in the first two years since enactment, but there have also been many problems. During the three-year strict pandemic control period, the normal process of Environmental Protection Tax Law implementation was impacted, causing alienation and reducing the quality of implementation. This study empirically reveals the alienation mechanism in the implementation of the Environmental Protection Tax Law by taking 1000 Chinese tax professionals, and randomly divides the sample equally into two parts, utilizing 500 samples for the initial test and another 500 samples for the robustness test. This research shows that pollutant emission monitoring (correlation coefficient is 0.07), preferential tax policies (correlation coefficient is 0.03) and the quality of tax personnel (correlation coefficient is 0.06) are not conducive to realizing the crowding-out effect of the Environmental Protection Tax Law, while preferential tax policies (correlation coefficient is 0.05), information-sharing platforms (correlation coefficient is 0.06) and the quality of tax personnel (correlation coefficient is 0.05) hinder the incentive effect, and the remaining elements passed the correlation coefficient test within certain confidence intervals. Therefore, the implementation of China's Environmental Protection Tax Law should be improved in the following ways: the accuracy of the environmental protection departments' supervision of pollutant emissions as well as the scientificity and rationality of preferential tax policies should be improved, the construction of environmental protection tax information-sharing platforms should be strengthened, and compound tax collection and management talent should be created.

New Challenges in Mathematical Modelling and Control of COVID-19 Epidemics: Analysis of Non-Pharmaceutical Actions and Vaccination Strategies

Since its official appearance in China in December 2019, COVID-19 (SARS-CoV-2)immediately reached pandemic proportions on six continents and in over 195 countries [...]

A comparative cost assessment of coalescing epidemic control strategies in heterogeneous social-contact networks

The outcome of an epidemic is contingent upon the mitigating control strategies deployed by policymakers. The deployment of control strategies is constrained by the cost of economic, social, and technological factors, which often depend on regional conditions. Our model facilitates a comparative assessment of costs between two interconnected subpopulations within a heterogeneous social-contact network, which may deploy either aligned or divergent control strategies, as is frequently the case for neighboring countries. Depending on their respective asymmetric resources, each subpopulation can deploy a contact confinement strategy, a vaccination strategy, or a hybrid of both. The multi-objective goal of minimizing both the epidemic burden and the economic cost from policy implementation and productivity losses is compounded using a scaled scalarization method. Due to the inter-dependence of policy outcomes, the optimal strategy is derived from the Nash equilibrium in a 2-player compounded pay-off matrix of the total cost. Our network-based model implements a probabilistic Susceptible-Exposed-Infectious-Recovered-Dead dynamics. It also includes the effects of ego-network support and waning immunity modulated by re-exposure to viral contaminants (‘SEIRSD’). Robust outcomes of repeated network simulations with COVID-19 parameters are examined. Our method aims to equip policymakers in a negotiation process with a comparative cost matrix for divergent mitigation policies and to identify the optimal Nash-based strategy profile.

Evolution, control and success of combination therapy with Ampicilin-sulbactam/Ceftazidime-Avibactam during a Carbapenem-Resistant Acinetobacter baumannii outbreak in burn Intensive Care Unit.

We present our findings on interpatient transmission, epidemic control measures, and the outcomes of a series of ten critically ill burn patients who were either colonized or infected with carbapenem-resistant Acinetobacter baumannii (CRAB). None of the five infected patients achieved clinical cure, and all experienced relapses. Microbiological failure was observed in 40% of the infected patients. The isolated CRAB strains were found to carry blaOXA-23 and armA resistance genes. Despite the lack of clinical cure, all five infected patients survived and were discharged from the Burn Intensive Care Unit.

Investigating the influence of risk perception on females’ public service motivation during public health emergencies

Since the inception of Public Service Motivation (PSM) by Perry and Wise, substantial research has been conducted in this domain. However, there is a dearth of scholarly investigation into the impact of changing public service environments, specifically the perception of workplace risk, on public service motivation. Recent public health crises, such as the COVID-19 pandemic, have necessitated significant changes in frontline public employees’ work environments. As they frequently engage in epidemic prevention and control activities, which entail direct exposure to the virus, their motivation may fluctuate based on their perceived risks. Female employees, in particular, facing the dual pressures of work and family responsibilities, are more prone to being affected. Drawing upon the human behavioral motivation and Stress-Strain-Outcome framework, this study examines the influence mechanism of risk perception on public service motivation among 214 female employees who participated in epidemic control during the 2022 lockdown period in Shanghai. As the findings indicate, risk perception detrimentally affects their public service motivation both directly and indirectly through emotional exhaustion or anxiety-emotional exhaustion dual mediation, whereas anxiety does not mediate such a relationship. The study’s theoretical significance lies in its potential to broaden the scope of antecedent research on public service motivation and address the research gap about the mechanisms through which risk perception influences public service motivation during public health emergencies. Practically, these insights may assist public organizations in mitigating the adverse effects of risk perception, thereby enhancing their employees’ well-being and service effectiveness.

Investigation and Prediction of Outdoor Thermal Comfort under Different Protection and Activity Intensity Conditions in Summer in Wuhan

In the context of normalized epidemic prevention and control, the impact of masks and protective clothing on personal thermal comfort cannot be overlooked. To investigate the thermal comfort of outdoor personnel under various protective conditions, this study took Wuhan as an example and evaluated the outdoor thermal comfort of subjects under different protection and activity conditions through thermal environment monitoring, physiological measurements, and thermal comfort questionnaires. The results show significant differences in the PET thermal comfort baseline under various protective conditions. To address the problem that most areas have not yet established state-specific thermal comfort baselines, a State Outdoor Comfort Index (SOCI) model was developed to correct the insensitivity of PET indicators to clothing thermal resistance and metabolic rate. Finally, the performance of the SOCI model was evaluated through statistical indicators, demonstrating its good predictive capability. This study provides appropriate quantitative indicators to improve the thermal comfort of outdoor personnel.

Use of bio-information and communication technology shortens time to peak at a lower height of the epidemic curve: An alternative to flattening for countries with early COVID-19 outbreaks.

The traditional approach to epidemic control has been to slow down the rate of infection while building up healthcare capacity, resulting in a flattened epidemic curve. Advancements in bio-information-communication technology (BICT) have enabled the preemptive isolation of infected cases through efficient testing and contact tracing. This study aimed to conceptualize the BICT-enabled epidemic control (BICTEC) and to document its relationships with epidemic curve shaping and epidemic mitigation performance. Daily COVID-19 incidences were collected from outbreak to Aug. 12, 2020, for nine countries reporting the first outbreak on or before Feb. 1, 2020. Key epidemic curve determinants-peak height (PH), time to peak (TTP), and area under the curve (AUC)-were estimated for each country, and their relationships were analyzed to test if epidemic curves peak quickly at a shorter height. CFR (Case Fatality Rate) and CI (Cumulative Incidence) were compared across the countries to identify relationships between epidemic curve shapes and epidemic mitigation performance. China and South Korea had the quickest TTPs (40.70 and 45.37 days since outbreak, respectively) and the shortest PHs (2.95 and 4.65 cases per day, respectively). Sweden, known for its laissez-faire approach, had the longest TTP (120.36) and the highest PH (279.74). Quicker TTPs were correlated with shorter PHs (ρ = 0·896, p = 0·0026) and lower AUCs (0.790, p = 0.0028), indicating that epidemic curves do not follow a flattened trajectory. During the study period, countries with quicker TTPs tended to have lower CIs (ρ = .855, P = .006) and CFRs (ρ = 0.684, P = .061). For example, South Korea, with the second-quickest TTP, reported the second lowest CI and the lowest CFR. Countries that experienced early COVID-19 outbreaks demonstrated the epidemic curves that quickly peak at a shorter height, indicating a departure from the traditional flattened trajectory. South Korea's BICTEC was found to be at least as effective as most lockdowns in reducing CI and CFR.

Geospatial analysis and prevalence of Schistosoma mansoni and soil-transmitted helminth infections in an endemic area in Eastern Brazilian Amazon.

This study evaluated the occurrence of Schistosoma mansoni and soil-transmitted helminths in an endemic area in the Eastern Brazilian Amazon, analysing prevalence and spatial distribution. The study was conducted in four localities of Primavera Municipality, in Pará state. Data was obtained from the Decit 40/2012 project and the participants were divided into five age range categories for evaluation: children, adolescents, young adults, adults and elderly individuals. For the diagnostic tests, Kato-Katz slides were prepared to detect S. mansoni and soil-transmitted helminths eggs. The spatial distribution map and the Kernel Density Estimation were performed to assess the presence and location of infections. Stool samples revealed the presence of hookworms, S. mansoni, Ascaris lumbricoides and Trichuris trichiura eggs. Mono-, bi- and poly-parasitic infections were observed, with a significant prevalence of hookworm monoparasitism. The high frequency of children infected with soil-transmitted helminths confirms their significance as an ongoing public health problem in the poorest municipalities of Brazil. The Geographic Information System plays a crucial role in environmental surveillance and in the control of epidemics and endemic diseases, enabling accurate assessment and informed decision-making for their control.

Investigation on KAP Model of Urban Residents in Prevention and Control of COVID-19

Objective: To investigate the knowledge, attitude and practice of the residents in Changxing community in the prevention and control of novel coronavirus pneumonia, and put forward targeted suggestions for formulating epidemic prevention and control measures. Methods: Convenience sampling method was used to invite residents to fill in the self-designed questionnaire online. Results: Total of 294 valid questionnaires were obtained. Among them, the awareness rates of the infectious source, transmission route, incubation period and epidemic situation of COVID-19 were 84.7%, 94.2%, 90.1% and 83.0% respectively. The proportions of judging that COVID-19 has high infectious characteristics, low mortality and high cure rate were 89.5%, 40.1% and 62.6%. The proportions of mastering the knowledge of preventive behaviors such as wearing masks, avoiding family and friends' gatherings, and washing hands correctly were 98.0%, 96.6% and 90.8%; The level of attitude towards epidemic prevention and control measures and awareness of prevention behavior exceeded 90%. Conclusion: The knowledge, attitude and practice of residents in Changxing community on COVID-19 are good.