Transmission Of Contagious Diseases Research Articles

Exploring Hopf-bifurcations and endemic bubbles in a tuberculosis model with behavioral changes and treatment saturation.

To manage risks and minimize the transmission of contagious diseases, individuals may reduce their contact with each other and take other precautions as much as possible in their daily lives and workplaces. As a result, the transmission of the infection reduces due to the behavioral changes. These behavioral changes are incorporated into models by introducing saturation in disease incidence. In this article, we propose and analyze a tuberculosis model that incorporates saturated exogenous reinfection and treatment. The stability analysis of the model's steady states is rigorously examined. We observe that the disease-free equilibrium point and the endemic equilibrium point (EEP) are globally asymptotically stable if the basic reproduction number (R0) is less than 1 and greater than 1, respectively, only when exogenous reinfection is not present (p=0) and when treatment is available for all (ω=0). However, even when R0 is less than 1, tuberculosis may persist at a specific level in the presence of exogenous reinfection and treatment saturation, leading to a backward bifurcation in the system. The existence and direction of Hopf-bifurcations are also discussed. Furthermore, we numerically validate our analytical results using different parameter sets. In the numerical examples, we study Hopf-bifurcations for parameters such as β, p, α, and ω. In one example, we observe that increasing β leads to the loss of stability of the unique EEP through a forward Hopf-bifurcation. If β is further increased, the unique EEP restores its stability, and the bifurcation diagram exhibits an interesting structure known as an endemic bubble. The existence of an endemic bubble for the saturation constant ω is also observed.

The impact of social media advertisements and treatments on the dynamics of infectious diseases with optimal control strategies

The dissemination of public health information through television and social media posts is essential for informing the public about the transmission of contagious diseases, which is crucial in preventing the spread of various infectious diseases. In this paper, we propose a non-linear mathematical model to assess the effect of advertisements through social media in creating awareness and limiting treatment on spreading infectious diseases. These initiatives may alter population behaviour and divide the susceptible population into subgroups. In addition, to comprehend these dynamics better, we use half-saturation constant rates for media coverage and treatment. The model’s well-posedness and feasibility are evaluated. The possible biological equilibrium points are calculated. Local and global stability are carried out. The objective of our study is to produce the model’s bifurcation. Transcritical, Saddle–node, Hopf bifurcation of codimension 1 and Cusp, Generalized-Hopf (Bautin), and Bogdanov–Takens (BT) bifurcation of codimension 2 are studied for this purpose. Due to the limited medical resources and supply efficiency, the model exhibits backward bifurcation, resulting in bistability. Moreover, the occurrence condition for stability and direction of Hopf bifurcation is discussed. This model study demonstrates that the system is significantly influenced by the pace with which awareness programmes are implemented and that raising this value above a threshold may result in continuous oscillation. Sensitivity analysis employs the normalized forward sensitivity index of the basic reproduction number to provide a comprehensive understanding of the effect of various parameters on accelerating and limiting disease spread. Further, the minimum possible cost is determined by formulating an optimal control system based on sensitivity analysis and applying Pontryagin’s maximum principle. Methods of cost-effectiveness, such as ACER and ICER, are used to determine the most cost-effective control intervention strategy among all the strategies. Numerical simulations have been done to support all theoretical findings.

Assessing the Knowledge and Adherence of Dental Students to Cross-Infection Control Measures

Background: Cross-infection control is extremely pivotal to halt the propagation of contiguous diseases amongst people as they pose a tremendously increasing disease burden on our health care system. Therefore, this study aimed to assess the knowledge and adherence to cross-infection control measures among dental students in public and private institutions in Karachi. Methods: This descriptive study was performed among dental students of public and private sector dental colleges in Karachi from January 2020 – February 2020. The questionnaire assessed the knowledge and adherence of dental students toward cross-infection control protocols during their clinical rotations. The chi-square test was used to analyze the relationship between students’ knowledge and practice of cross-infection control measures. Results: A total of 202 students participated in this study. The students demonstrated adequate knowledge of cross-infection control measures. However, the practice of wearing gloves was positive (98%) in contrast to the use of masks (79%), gowns (46%), and eyewear (13%). A statistically significant relation was seen in their knowledge and attitude toward hand hygiene. The immunization status of students from both government (72%) and private (88%) sectors raised concerns. Although students demonstrated good practice of measures to avoid transmission of contagious diseases (p=<0.001) apart from the use of environmental barrier (36%) (p=0.047) and disinfection (37%) of the working surface. Conclusion: The overall knowledge of cross-infection control was satisfactory among dental students. Efforts are needed to improve the degree of compliance with recognized policies for improving the attitude of students regarding cross-infection measures.

Knowledge, Attitude, and Self-reported Practices on Prevention of Respiratory Infections among Two Groups of Islamic Pilgrims, Thailand, 2021

Religious mass gatherings can foster contagious disease transmission in the home countries of pilgrims. Thailand has two major Muslim pilgrims: the Hajj and the Dawah. This study aimed to compare their knowledge (K), attitude (A), and self-reported practice (P), and qualitatively evaluate their perceptions regarding the prevention of respiratory infections. A cross-sectional mixed methods study was conducted. Multistage sampling was conducted in Hajj participants, while convenience sampling was used with the Dawah participants at two gathering places. Pearson’s chi-square test was used to compare KAP scores between the two groups. We conducted qualitative interviews with 13 purposively chosen participants. There were 111 Hajj and 228 Dawah participants. Most Hajj respondents were in the age group of ≥50 years, while most Dawah respondents were between 30–49 years. Overall, the Hajj group had a significantly higher proportion of good knowledge scores than the Dawah group, with 76.6 and 56.1, as well as the positive attitude score of 97.3 and 87.7. The Hajj group was more receptive to receive health education about respiratory infections before their pilgrimage. Preparatory education classes should be initiated for Dawah Muslims before they attend a foreign gathering event.

The role of the California tier system in controlling population mobility during the COVID-19 pandemic

BackgroundPolicies to restrict population mobility are a commonly used strategy to limit the transmission of contagious diseases. Among measures implemented during the COVID-19 pandemic were dynamic stay-at-home orders informed by real-time, regional-level data. California was the first state in the U.S. to implement this novel approach; however, the effectiveness of California’s four-tier system on population mobility has not been quantified.MethodsUtilizing data from mobile devices and county-level demographic data, we evaluated the impact of policy changes on population mobility and explored whether demographic characteristics explained variability in responsiveness to policy changes. For each California county, we calculated the proportion of people staying home and the average number of daily trips taken per 100 persons, across different trip distances and compared this to pre-COVID-19 levels.ResultsWe found that overall mobility decreased when counties moved to a more restrictive tier and increased when moving to a less restrictive tier, as the policy intended. When placed in a more restrictive tier, the greatest decrease in mobility was observed for shorter and medium-range trips, while there was an unexpected increase in the longer trips. The mobility response varied by geographic region, as well as county-level median income, gross domestic product, economic, social, and educational contexts, the prevalence of farms, and recent election results.ConclusionsThis analysis provides evidence of the effectiveness of the tier-based system in decreasing overall population mobility to ultimately reduce COVID-19 transmission. Results demonstrate that socio-political demographic indicators drive important variability in such patterns across counties.

Human Amniotic Membrane Usage from Bench to Bedside in Congenital Defects and Wounds in Paediatric Surgery: A Systematic Review

Background: The restricted donor area in paediatric patients demands the use of Human Amniotic membrane (hAM) in the management of difficult-to-manage wounds. It can be used directly over wounds or used to grow stem cells by different culture methods. The hAM can be used “fresh” i.e., +4O glycerol preserved or “cryopreserved”. Methods: In this literature review, we searched ‘PubMed’, ’Web of Science’ and ’SCOPUS’ for experimental models, RCT, Observational studies, case series, and case reports involving the usage of hAM in the treatment of neonatal and paediatric (​<14 yrs.) patients, published in from 1993 to April 2022. The search included the keywords, “amnion”, “biomaterials”, “biological dressing”, “clinical study”, “congenital defects”, “human amniotic membrane”, “paediatric wound”, “neonatal wounds”, and “regenerative medicine”. The Search was extended by snowballing the reference list of all included studies. Results: The final analysis included one experimental RCT, three review articles, and twelve case reports. The experimental studies were in rat, pup, and porcine models. The paediatric second-and third-degree thermal burn followed by paediatric ocular diseases viz corneal epithelial ulcers, conjunctiva reconstruction following Steven Johnson Syndrome, and scarring after surgery of strabismus were the most common indications for the usage of AM. Five cases of meningomyelocele repair (intradural & extradural placement of AM) and 2 cases of gastroschisis repair (as an antiadhesive layer) were reported. Freeze-dried hAM is most frequently used in clinical practice. Autologous hAM was used in antenatally detected birth defects. In the adults, the fresh hAM was found equally effective as freeze-dried AM, but with the risk of transmission of contagious diseases. The literature on Fresh amnion is deficient in paediatric patients. Conclusion: hAM as a skin substitute in paediatric wounds/defects has shown an enhanced rate of healing. However, further studies, regarding the utility of hAM in the management of paediatric wounds, congenital anatomical defects, and diseases along with analysis of outcome and economic constraints in developing countries are needed.

Evaluation of feasibility and user acceptance of lateral-flow self-testing for viral illness in a residential treatment rehabilitation facility

BackgroundThe role of rapid testing has proven vital in reducing infection incidence in communities through swift identification and isolation of infected individuals. The COVID-19 pandemic has been particularly catastrophic for residential carceral and rehabilitation facilities that are high-risk settings for transmission of contagious diseases. Centralized provider-based viral testing employing conventional diagnostic techniques is labor-intensive and time-consuming. There is a marked unmet need for quick, inexpensive, and simple viral testing strategies. We hypothesized that rehabilitation residents could successfully test themselves employing inexpensive, disposable, antigen-based influenza lateral-flow tests and would be willing to self-isolate and self-report to health authorities if positive.MethodsWe evaluated self-testing among 50 rehabilitation residents ages 18 and older in Pomona, California, where participants self-administered influenza lateral-flow diagnostic test (without specimen collection) with the goal of appropriately observing a control line and completed two brief written surveys on self-testing and COVID-19, one before self-administering the lateral-flow test and one after, to determine the overall feasibility of viral self-testing and to characterize attitudes comparing self-testing and provider-based testing.FindingsA total of 50 rehabilitation residents were enrolled in this study and all 50 conducted a lateral-flow test and answered the provided surveys. Among the participants, 96% (48 of 50) achieved a positive-control line from their lateral-flow test. Most participants, 83% (34 of 41) indicated that they would prefer to perform their own rapid test instead of having a health care provider administer the test. Notably, 98% (49 of 50) indicated that they would self-isolate if the lateral-flow test returned a positive indicator suggesting the presence of a viral infection and 96% (48 of 50) would report positive results to their corresponding public health department.InterpretationResidents in a residential rehabilitation center were widely able to successfully self-administer standard lateral-flow antigen-based rapid diagnostic kits. Self-testing was strongly preferred over tests administered by a healthcare provider. Reassuringly, almost every resident indicated that they would report any positive test result to the health department and self-isolate accordingly. Self-testing offers a promising adjunct to centralized testing, potentially better enabling swift and effective management of life-threatening infectious outbreaks among those living in high-risk congregate living settings.

Influence of Gender, Age and Field of Study on Hand Hygiene in Young Adults: A Cross-Sectional Study in the COVID-19 Pandemic Context.

The effectiveness of hand hygiene (HH) on reducing the transmission of contagious diseases is widely known, although its use has been commonly associated with the area of healthcare. During the COVID-19 pandemic, HH was one of the main measures established to contain the transmission of this virus. The identification of the main barriers and facilitators of HH in young adults (aged 18–29 years old) will contribute to the better planning of HH training and its posterior success. A total of 716 young adults participated in the study by completing the ad hoc online questionnaire (#YesWeHand), which analyzed, among other aspects, the age range, gender and field of study that they belonged to. From the total participants, 81.3% indicated knowing how to perform HH correctly, while 49.4% affirmed having received training. The main reason for performing HH was concern for their own safety and that of others (75.8%), while forgetfulness (36.5%) was the main reason for not performing HH. In the group of young adults, being female, aged between 22 and 25 years old, and having studied in the area of Health Sciences, had a positive influence on correct HH. It is deemed necessary to maintain HH beyond the primary education stages, and to adapt it to different fields of education, ages, and genders, in order to maximize its success. Given the overrepresentation of participants from the healthcare field, it would be desirable to conduct more studies to ensure a better representation of the different educational levels and fields of study of the participants, in order to identify, in a more reliable way, the variables that influence HH.

Preclinical evaluation of noncontact vital signs monitoring using real-time IR-UWB radar and factors affecting its accuracy

Recently, noncontact vital sign monitors have attracted attention because of issues related to the transmission of contagious diseases. We developed a real-time vital sign monitor using impulse-radio ultrawideband (IR-UWB) radar with embedded processors and software; we then evaluated its accuracy in measuring heart rate (HR) and respiratory rate (RR) and investigated the factors affecting the accuracy of the radar-based measurements. In 50 patients visiting a cardiology clinic, HR and RR were measured using IR-UWB radar simultaneously with electrocardiography and capnometry. All patients underwent HR and RR measurements in 2 postures—supine and sitting—for 2 min each. There was a high agreement between the RR measured using radar and capnometry (concordance correlation coefficient [CCC] 0.925 [0.919–0.926]; upper and lower limits of agreement [LOA], − 2.21 and 3.90 breaths/min). The HR measured using radar was also in close agreement with the value measured using electrocardiography (CCC 0.749 [0.738–0.760]; upper and lower LOA, − 12.78 and 15.04 beats/min). Linear mixed effect models showed that the sitting position and an HR < 70 bpm were associated with an increase in the absolute biases of the HR, whereas the sitting position and an RR < 18 breaths/min were associated with an increase in the absolute biases of the RR. The IR-UWB radar sensor with embedded processors and software can measure the RR and HR in real time with high precision. The sitting position and a low RR or HR were associated with the accuracy of RR and HR measurement, respectively, using IR-UWB radar.

Detection of Brucella abortus during in vitro bovine embryo production

The in vitro embryo production (IVP) technology has emerged as a potential biotechnological approach to multiply genetically high yielding dairy cows. Its commercial application is increasing in many developed and developing countries over the years. Bangladesh livestock Research Institute (BLRI) adopted in vitro embryo production protocol from bovine ovaries of slaughterhouse. However, the risks of transmission of contagious diseases like Brucella abortus with embryos are not evaluated so far. Considering these facts, the present experiments were conducted to evaluate the efficiency of in vitro embryo production protocol with slaughterhouse ovaries as well as risk of contamination of produced embryos with Brucella abortus. To identify sources of contamination of embryos with Brucella abortus (if any), the laboratory water, different media used in the IVP process, semen, and follicular fluids were evaluated for confirmation of the organisms. In addition, vaginal swabs were collected from 2 buffaloes aborted due to suspected Brucella abortus infection. Molecular test were used to detect Brucella abortus contamination. Brucella abortus specific PCR product was not detected on agarose gel electrophoresis. The efficiency of IVP measured by cleavage and blastocyst development rates were 75.5±2.7% and 16.6±3.9%, respectively. The present study inferred that the in vitro produce embryos are free from Brucella abortus infection. Bang. J. Livs. Res. Vol. 27 (1&amp;2), 2020: P. 105-112

Triple contagion: a two-fears epidemic model.

We present a differential equations model in which contagious disease transmission is affected by contagious fear of the disease and contagious fear of the control, in this case vaccine. The three contagions are coupled. The two fears evolve and interact in ways that shape distancing behaviour, vaccine uptake, and their relaxation. These behavioural dynamics in turn can amplify or suppress disease transmission, which feeds back to affect behaviour. The model reveals several coupled contagion mechanisms for multiple epidemic waves. Methodologically, the paper advances infectious disease modelling by including human behavioural adaptation, drawing on the neuroscience of fear learning, extinction and transmission.

Scalable Estimation of Epidemic Thresholds via Node Sampling.

Infectious or contagious diseases can be transmitted from one person to another through social contact networks. In today’s interconnected global society, such contagion processes can cause global public health hazards, as exemplified by the ongoing Covid-19 pandemic. It is therefore of great practical relevance to investigate the network transmission of contagious diseases from the perspective of statistical inference. An important and widely studied boundary condition for contagion processes over networks is the so-called epidemic threshold. The epidemic threshold plays a key role in determining whether a pathogen introduced into a social contact network will cause an epidemic or die out. In this paper, we investigate epidemic thresholds from the perspective of statistical network inference. We identify two major challenges that are caused by high computational and sampling complexity of the epidemic threshold. We develop two statistically accurate and computationally efficient approximation techniques to address these issues under the Chung-Lu modeling framework. The second approximation, which is based on random walk sampling, further enjoys the advantage of requiring data on a vanishingly small fraction of nodes. We establish theoretical guarantees for both methods and demonstrate their empirical superiority.

An innovative protocol for the artificial speech-directed, contactless administration of laboratory-based comprehensive cognitive assessments: PAAD-2 trial management during the COVID-19 pandemic

The COVID-19 pandemic resulted in suspending in-person human subject research across most institutions in the US. Our extensive cognitive assessment for a phase-2 clinical trial, Physical Activity and Alzheimer's Disease–2 (PAAD-2), was also paused in March 2020. It was important to identify strategies to mitigate the risk of COVID-19 transmission during our testing, which initially required substantial human speech and close person-to-person contact for test directions and instant feedback on paper/pencil tests. Given current understanding of the COVID-19 transmission, we dramatically adjusted the testing protocol to minimize the production of speech droplets and allow social distancing while maintaining the integrity of testing. We adopted state-of-the-art speech synthesis and computerization techniques to create an avatar to speak on behalf of the experimenter for all verbal instructions/feedback, used a document camera to observe the paper/pencil tests from the required distances, and automated the testing sequence and timing. This paper aims 1) to describe an innovative laboratory-based cognitive testing protocol for a completely contact-free, computer-speaking, and semi-automated administration; and 2) to evaluate the integrity of the modified protocol (n = 37) compared with the original protocol (n = 32). We have successfully operated the modified protocol since July 2020 with no evidence of COVID-19 transmission during testing, and data support that the modified protocol is robust and captures data identical to the original protocol. This transition of data collection methods has been critical during the pandemic and will be useful in future studies to mitigate the risk of contagious disease transmission and standardize laboratory-based psychological tests.Trial registration: ClinicalTrials.gov NCT03876314. Registered March 15, 2019

Towards human distance estimation using a thermal sensor array

Human distance estimation is essential in many vital applications, specifically, in human localisation-based systems, such as independent living for older adults applications, and making places safe through preventing the transmission of contagious diseases through social distancing alert systems. Previous approaches to estimate the distance between a reference sensing device and human subject relied on visual or high-resolution thermal cameras. However, regular visual cameras have serious concerns about people’s privacy in indoor environments, and high-resolution thermal cameras are costly. This paper proposes a novel approach to estimate the distance for indoor human-centred applications using a low-resolution thermal sensor array. The proposed system presents a discrete and adaptive sensor placement continuous distance estimators using classification techniques and artificial neural network, respectively. It also proposes a real-time distance-based field of view classification through a novel image-based feature. Besides, the paper proposes a transfer application to the proposed continuous distance estimator to measure human height. The proposed approach is evaluated in different indoor environments, sensor placements with different participants. This paper shows a median overall error of pm 0.2 m in continuous-based estimation and 96.8% achieved-accuracy in discrete distance estimation.

Structural modeling and phylogenetic analysis for infectious disease transmission pattern based on maximum likelihood tree approach.

The contagious disease transmission pattern outbreak caused a massive human casualty and became a pandemic, as confirmed by the World Health Organization (WHO). The present research aims to understand the infectious disease transmission pattern outbreak due to molecular epidemiology. Hence, infected patients over time can spread infectious disease. The virus may develop further mutations, and that there might be a more toxic virulent strain, which leads to several environmental risk factors. Therefore, it is essential to monitor and characterize patient profiles, variants, symptoms, geographic locations, and treatment responses to analyze and evaluate infectious disease patterns among humans. This research proposes the Evolutionary tree analysis (ETA) for the molecular evolutionary genetic analysis to reduce medical risk factors. Furthermore, The Maximum likelihood tree method (MLTM) has been used to analyze the selective pressure, which is examined to identify a mutation that may influence the infectious disease transmission pattern’s clinical progress. This study also utilizes ETA with Markov Chain Bayesian Statistics (MCBS) approach to reconstruct transmission trees with sequence information. The experimental shows that the proposed ETA-MCBS method achieves a 97.55% accuracy, prediction of 99.56%, and 98.55% performance compared to other existing methods.

Evaluation of Feasibility and User Acceptance of Lateral-Flow Self Testing for Viral Illness in a Correctional Center Rehabilitation Facility

Background: The role of rapid testing has proven vital in reducing infection incidence in communities through swift identification and isolation of infected individuals. The COVID-19 pandemic has been particularly catastrophic for residential carceral and rehabilitation facilities that are high-risk settings for transmission of contagious diseases. Centralized provider-based viral testing employing conventional diagnostic techniques is labor-intensive and time consuming. There is a marked unmet need for quick, inexpensive, and simple viral testing strategies. We hypothesized that rehabilitation residents could successfully test themselves employing inexpensive, disposable, antigen-based lateral-flow tests and would be willing to self-isolate and self-report to health authorities if positive.Methods: We evaluated self-testing among 50 rehabilitation residents ages 18 and older in Pomona, California, where participants self-administered an influenza lateral-flow diagnostic test (without specimen collection) with the goal of appropriately observing a control line and completed two brief written surveys, one before self-administering the lateral-flow test and one after, to determine the overall feasibility of viral self-testing and to characterize attitudes comparing self-testing and provider-based testing.Findings: A total of 50 rehabilitation residents were enrolled in this study and all 50 conducted a lateral-flow test and answered the provided surveys. Among the participants, 96% (48 of 50) achieved a positive-control line from their lateral-flow test. Most participants, 83% (34 of 41) indicated that they would prefer to perform their own rapid test instead of having a health care provider administer the test. Notably, 98% (49 of 50) indicated that they would self-isolate if the lateral-flow test returned a positive indicator suggesting the presence of a viral infection and 96% (48 of 50) would report positive results to their corresponding public health department.Interpretation: Residents in a residential rehabilitation center were widely able to successfully self-administer standard lateral-flow antigen-based rapid diagnostic kits. Self-testing was strongly preferred over tests administered by a healthcare provider. Reassuringly, almost every resident indicated that they would report any positive test result to the health department and self-isolate accordingly. Self-testing offers a promising adjunct to centralized testing, potentially better enabling swift and effective management of life-threatening infectious outbreaks among those living in high-risk congregate living settings.Funding: This study was funded by a grant awarded to Benjamin Sievers from the Pitzer College Racial Justice Initiative.Declaration of Interest: None to declare. Ethical Approval: This study was approved by both the Institutional Review Board at Pitzer College and HealthRIGHT 360’s IRB committee, project number: 2020-32R1. Pitzer College’s institutional review board’s review was carried out in accordance with the requirements of Part 46, “Protection of Human Subjects” of Title 45 of the Code of Federal Regulations and the “US Department of Health and Human Services (DHHS) Federal-Wide Assurance (FWA) for the Protection of Human Subjects for Domestic (US) Institutions,” Pitzer College Assurance #FWA00001138.

Managing outbreaks of highly contagious diseases in prisons: a systematic review

BackgroundThere are reports of outbreaks of COVID-19 in prisons in many countries. Responses to date have been highly variable and it is not clear whether public health guidance has been...

Managing Outbreaks of Highly Contagious Diseases in Prisons: A Systematic Review

Background: There are reports of outbreaks of coronavirus disease 2019 (Covid-2019) in prisons in many countries. Responses to date have been highly variable and it is not clear whether public health guidance has been informed by the best available evidence. We conducted a systematic review to synthesise the evidence on outbreaks of highly contagious diseases in prison. Methods: We searched seven electronic databases for peer-reviewed articles and official reports published between 1 January 2000 and 26 March 2020. We excluded studies that did not provide detail on interventions. We synthesized common themes using SWiM guidelines, identified gaps in the literature and critically appraised the effectiveness of various containment approaches. Findings: We identified 27 relevant studies. Investigations were all based in high-income countries and documented outbreaks of tuberculosis, influenza (types A and B), varicella, measles, mumps, and adenovirus. Several themes were common to these reports, including the public health implications of infectious disease outbreaks in prison, and the role of multi-agency collaboration, health communication, screening for contagious diseases, restriction, isolation and quarantine, contact tracing, immunisation programmes, surveillance, and prison-specific guidelines in addressing any outbreaks. Interpretation: Prisons are high-risk settings for the transmission of contagious diseases and there are considerable challenges in managing outbreaks in them. A public health approach to managing Covid-19 in prisons is required.

Health effects of flooding in Canada: A 2015 review and description of gaps in research

Worldwide, floods are the most common natural disaster and produce a broad array of health impacts. In Canada, it is difficult to quantify all of the health impacts associated with flooding. This data gap is salient because of the increasing risks floods are posing to society as a result of climate change. This paper reviews the epidemiological evidence of flood-related health effects, and the Canadian susceptibility to these effects. The health impacts from flooding range from mortality, drowning and other injuries to hypothermia, mental health impacts, deterioration of elderly/patients who required emergency transportation, homelessness and transmission of contagious diseases and others. The Canadian population includes a range of socio-economic levels, demographics and pre-existing illness. Additionally, many Canadians live and work in flood plains or on shorelines where floods are a hazard. There is, therefore, variable susceptibility to flood events in the population. Susceptibility to these health impacts can be buffered by the population’s adaptive capacity and external support. To ensure the safety and health of the Canadian population, government and non-profit organizations can decrease the burden of flooding by increasing adaptive capacity, emergency response and a focus on preventative measures. Vulnerable populations who require extra support to avoid negative health impacts from flooding, such as First Nations populations, need further attention. Recommendations are offered for addressing the health-related effects of flooding.

Modeling Spatial Contacts for Epidemic Prediction in a Large-Scale Artificial City

Spatial contacts among human beings are considered as one of the influential factors during the transmission of contagious diseases, such as influenza and tuberculosis. Therefore, representing and understanding spatial contacts plays an important role in epidemic modeling research. However, most current research only considers regular spatial contacts such as contacts at home/school/office, or they assume static social networks for modeling social contacts and omit travel contacts in their epidemic models. This paper describes a way to model relatively complete spatial contacts in the context of a large-scale artificial city, which combines different data sources to construct an agent-based model of the city Beijing. In this model, agents have regular contacts when executing their daily activity patterns which is similar to other large-scale agent-based epidemic models. Besides, a microscopic public transportation component is included in the artificial city to model public travel contacts. Moreover, social contacts also emerge in this model due to the dynamic generation of social networks. To systematically examine the effect of the relatively complete spatial contacts have for epidemic prediction in the artificial city, a pandemic influenza disease progression model was implemented in this artificial city. The simulation results validated the model. In addition, the way to model spatial contacts in this paper shows potential not only for improving comprehension of disease spread dynamics, but also for use in other social systems, such as public transportation systems and city level evacuation planning.