Travel distance and human movement predict paths of emergence and spatial spread of chikungunya in Thailand

AbstractHuman movement contributes to the probability that pathogens will be introduced to new geographic locations. Here we investigate the impact of human movement on the spatial spread of Chikungunya virus (CHIKV) in Southern Thailand during a recent re-emergence. We hypothesised that human movement, population density, the presence of habitat conducive to vectors, rainfall and temperature affect the transmission of CHIKV and the spatiotemporal pattern of cases seen during the emergence. We fit metapopulation transmission models to CHIKV incidence data. The dates at which incidence in each of 151 districts in Southern Thailand exceeded specified thresholds were the target of model fits. We confronted multiple alternative models to determine which factors were most influential in the spatial spread. We considered multiple measures of spatial distance between districts and adjacency networks and also looked for evidence of long-distance translocation (LDT) events. The best fit model included driving-distance between districts, human movement, rubber plantation area and three LDT events. This work has important implications for predicting the spatial spread and targeting resources for control in future CHIKV emergences. Our modelling framework could also be adapted to other disease systems where population mobility may drive the spatial advance of outbreaks.

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Variation in human mobility and its impact on the risk of future COVID-19 outbreaks in Taiwan

BMC Public Health ◽

10.1186/s12889-021-10260-7 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Meng-Chun Chang ◽

Rebecca Kahn ◽

Yu-An Li ◽

Cheng-Sheng Lee ◽

Caroline O. Buckee ◽

...

Keyword(s):

Disease Surveillance ◽

Initial Conditions ◽

Human Mobility ◽

Human Movement ◽

Disease Spread ◽

Spatial Spread ◽

Movement Data ◽

Intercity Travel ◽

Travel Restrictions ◽

The Impact

Abstract Background As COVID-19 continues to spread around the world, understanding how patterns of human mobility and connectivity affect outbreak dynamics, especially before outbreaks establish locally, is critical for informing response efforts. In Taiwan, most cases to date were imported or linked to imported cases. Methods In collaboration with Facebook Data for Good, we characterized changes in movement patterns in Taiwan since February 2020, and built metapopulation models that incorporate human movement data to identify the high risk areas of disease spread and assess the potential effects of local travel restrictions in Taiwan. Results We found that mobility changed with the number of local cases in Taiwan in the past few months. For each city, we identified the most highly connected areas that may serve as sources of importation during an outbreak. We showed that the risk of an outbreak in Taiwan is enhanced if initial infections occur around holidays. Intracity travel reductions have a higher impact on the risk of an outbreak than intercity travel reductions, while intercity travel reductions can narrow the scope of the outbreak and help target resources. The timing, duration, and level of travel reduction together determine the impact of travel reductions on the number of infections, and multiple combinations of these can result in similar impact. Conclusions To prepare for the potential spread within Taiwan, we utilized Facebook’s aggregated and anonymized movement and colocation data to identify cities with higher risk of infection and regional importation. We developed an interactive application that allows users to vary inputs and assumptions and shows the spatial spread of the disease and the impact of intercity and intracity travel reduction under different initial conditions. Our results can be used readily if local transmission occurs in Taiwan after relaxation of border control, providing important insights into future disease surveillance and policies for travel restrictions.

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Incubation periods impact the spatial predictability of cholera and Ebola outbreaks in Sierra Leone

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1913052117 ◽

2020 ◽

Vol 117 (9) ◽

pp. 5067-5073 ◽

Cited By ~ 3

Author(s):

Rebecca Kahn ◽

Corey M. Peak ◽

Juan Fernández-Gracia ◽

Alexandra Hill ◽

Amara Jambai ◽

...

Keyword(s):

Sierra Leone ◽

Incubation Period ◽

Population Connectivity ◽

Disease Spread ◽

Long Distance ◽

Spatial Spread ◽

Transmission Parameters ◽

Incubation Periods ◽

Using Data ◽

The Impact

Forecasting the spatiotemporal spread of infectious diseases during an outbreak is an important component of epidemic response. However, it remains challenging both methodologically and with respect to data requirements, as disease spread is influenced by numerous factors, including the pathogen’s underlying transmission parameters and epidemiological dynamics, social networks and population connectivity, and environmental conditions. Here, using data from Sierra Leone, we analyze the spatiotemporal dynamics of recent cholera and Ebola outbreaks and compare and contrast the spread of these two pathogens in the same population. We develop a simulation model of the spatial spread of an epidemic in order to examine the impact of a pathogen’s incubation period on the dynamics of spread and the predictability of outbreaks. We find that differences in the incubation period alone can determine the limits of predictability for diseases with different natural history, both empirically and in our simulations. Our results show that diseases with longer incubation periods, such as Ebola, where infected individuals can travel farther before becoming infectious, result in more long-distance sparking events and less predictable disease trajectories, as compared to the more predictable wave-like spread of diseases with shorter incubation periods, such as cholera.

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Incubation periods impact the spatial predictability of outbreaks: analysis of cholera and Ebola outbreaks in Sierra Leone

10.1101/19003525 ◽

2019 ◽

Author(s):

Rebecca Kahn ◽

Corey M. Peak ◽

Juan Fernández-Gracia ◽

Alexandra Hill ◽

Amara Jambai ◽

...

Keyword(s):

Infectious Diseases ◽

Sierra Leone ◽

Incubation Period ◽

Population Connectivity ◽

Disease Spread ◽

Long Distance ◽

Spatial Spread ◽

Transmission Parameters ◽

Incubation Periods ◽

The Impact

AbstractForecasting the spatiotemporal spread of infectious diseases during an outbreak is an important component of epidemic response. However, it remains challenging both methodologically and with respect to data requirements as disease spread is influenced by numerous factors, including the pathogen’s underlying transmission parameters and epidemiological dynamics, social networks and population connectivity, and environmental conditions. Here, using data from Sierra Leone we analyze the spatiotemporal dynamics of recent cholera and Ebola outbreaks and compare and contrast the spread of these two pathogens in the same population. We develop a simulation model of the spatial spread of an epidemic in order to examine the impact of a pathogen’s incubation period on the dynamics of spread and the predictability of outbreaks. We find that differences in the incubation period alone can determine the limits of predictability for diseases with different natural history, both empirically and in our simulations. Our results show that diseases with longer incubation periods, such as Ebola, where infected individuals can travel further before becoming infectious, result in more long-distance sparking events and less predictable disease trajectories, as compared to the more predictable wave-like spread of diseases with shorter incubation periods, such as cholera.Significance statementUnderstanding how infectious diseases spread is critical for preventing and containing outbreaks. While advances have been made in forecasting epidemics, much is still unknown. Here we show that the incubation period – the time between exposure to a pathogen and onset of symptoms – is an important factor in predicting spatiotemporal spread of disease and provides one explanation for the different trajectories of the recent Ebola and cholera outbreaks in Sierra Leone. We find that outbreaks of pathogens with longer incubation periods, such as Ebola, tend to have less predictable spread, whereas pathogens with shorter incubation periods, such as cholera, spread in a more predictable, wavelike pattern. These findings have implications for the scale and timing of reactive interventions, such as vaccination campaigns.

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Elementary spatial structures and dispersion of COVID-19: health geography directing responses to public health emergency in São Paulo State, Brazil

10.1101/2020.04.26.20080895 ◽

2020 ◽

Author(s):

Carlos Magno Castelo Branco Fortaleza ◽

Raul Borges Guimarães ◽

Rafael de Castro Catão ◽

Cláudia Pio Ferreira ◽

Gabriel Berg de Almeida ◽

...

Keyword(s):

Public Health ◽

Metropolitan Area ◽

Sao Paulo ◽

São Paulo ◽

Population Mobility ◽

Long Distance ◽

Public Health Policies ◽

Social Distancing ◽

Public Health Strategies ◽

The Impact

AbstractPublic health policies to contain the spread of COVID-19 rely mainly on non-pharmacological measures. Those measures, especially social distancing, are a challenge for developing countries, such as Brazil. In São Paulo, the most populous state in Brazil (45 million inhabitants), most COVID-19 cases up to April 18th were reported in the Capital and metropolitan area. However, the inner municipalities, where 20 million people live, are also at risk. As governmental authorities discuss the loosening of measures for restricting population mobility, it is urgent to analyze the routes of dispersion of COVID-19 in those municipalities. In this ecological study, we use geographical models of population mobility as patterns for spread of SARS-Cov-2 infection. Based on surveillance data, we identify two patterns: one by contiguous diffusion from the capital metropolitan area and other that is hierarchical, with long-distance spread through major highways to cities of regional relevance. We also modelled the impact of social distancing strategies in the most relevant cities, and estimated a beneficial effect in each and every setting studied. This acknowledgement can provide real-time responses to support public health strategies.

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Detecting behavioural changes in human movement to inform the spatial scale of interventions against COVID-19

PLoS Computational Biology ◽

10.1371/journal.pcbi.1009162 ◽

2021 ◽

Vol 17 (7) ◽

pp. e1009162

Author(s):

Hamish Gibbs ◽

Emily Nightingale ◽

Yang Liu ◽

James Cheshire ◽

Leon Danon ◽

...

Keyword(s):

Community Structure ◽

Spatial Scale ◽

Human Movement ◽

Human Interaction ◽

Long Distance ◽

Targeted Interventions ◽

Detection Techniques ◽

Mobility Data ◽

The Uk ◽

The Impact

On March 23 2020, the UK enacted an intensive, nationwide lockdown to mitigate transmission of COVID-19. As restrictions began to ease, more localized interventions were used to target resurgences in transmission. Understanding the spatial scale of networks of human interaction, and how these networks change over time, is critical to targeting interventions at the most at-risk areas without unnecessarily restricting areas at low risk of resurgence. We use detailed human mobility data aggregated from Facebook users to determine how the spatially-explicit network of movements changed before and during the lockdown period, in response to the easing of restrictions, and to the introduction of locally-targeted interventions. We also apply community detection techniques to the weighted, directed network of movements to identify geographically-explicit movement communities and measure the evolution of these community structures through time. We found that the mobility network became more sparse and the number of mobility communities decreased under the national lockdown, a change that disproportionately affected long distance connections central to the mobility network. We also found that the community structure of areas in which locally-targeted interventions were implemented following epidemic resurgence did not show reorganization of community structure but did show small decreases in indicators of travel outside of local areas. We propose that communities detected using Facebook or other mobility data be used to assess the impact of spatially-targeted restrictions and may inform policymakers about the spatial extent of human movement patterns in the UK. These data are available in near real-time, allowing quantification of changes in the distribution of the population across the UK, as well as changes in travel patterns to inform our understanding of the impact of geographically-targeted interventions.

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Population Mobility Trends, Deprivation Index and the Spatio-Temporal Spread of Coronavirus Disease 2019 in Ireland

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18126285 ◽

2021 ◽

Vol 18 (12) ◽

pp. 6285

Author(s):

Jamie M. Madden ◽

Simon More ◽

Conor Teljeur ◽

Justin Gleeson ◽

Cathal Walsh ◽

...

Keyword(s):

Population Density ◽

Substantial Reduction ◽

Temporal Correlation ◽

Human Movement ◽

Deprivation Index ◽

Population Mobility ◽

Increased Risk ◽

Spatio Temporal ◽

Low Incidence ◽

The Impact

Like most countries worldwide, the coronavirus disease (COVID-19) has adversely affected Ireland. The aim of this study was to (i) investigate the spatio-temporal trend of COVID-19 incidence; (ii) describe mobility trends as measured by aggregated mobile phone records; and (iii) investigate the association between deprivation index, population density and COVID-19 cases while accounting for spatial and temporal correlation. Standardised incidence ratios of cases were calculated and mapped at a high spatial resolution (electoral division level) over time. Trends in the percentage change in mobility compared to a pre-COVID-19 period were plotted to investigate the impact of lockdown restrictions. We implemented a hierarchical Bayesian spatio-temporal model (Besag, York and Mollié (BYM)), commonly used for disease mapping, to investigate the association between covariates and the number of cases. There have been three distinct “waves” of COVID-19 cases in Ireland to date. Lockdown restrictions led to a substantial reduction in human movement, particularly during the 1st and 3rd wave. Despite adjustment for population density (incidence ratio (IR) = 1.985 (1.915–2.058)) and the average number of persons per room (IR = 10.411 (5.264–22.533)), we found an association between deprivation index and COVID-19 incidence (IR = 1.210 (CI: 1.077–1.357) for the most deprived quintile compared to the least deprived). There is a large range of spatial heterogeneity in COVID-19 cases in Ireland. The methods presented can be used to explore locally intensive surveillance with the possibility of localised lockdown measures to curb the transmission of infection, while keeping other, low-incidence areas open. Our results suggest that prioritising densely populated deprived areas (that are at increased risk of comorbidities) during vaccination rollout may capture people that are at risk of infection and, potentially, also those at increased risk of hospitalisation.

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The methodological approach for the determination of the pressure of artificial raindrops as a question of the theory of splash soil erosion

Melioration and Water Management ◽

10.32962/0235-2524-2019-1-24-28 ◽

2020 ◽

pp. 24-28

Author(s):

Mihail Zver'kov

Keyword(s):

Block Diagram ◽

Methodological Approach ◽

Control Measures ◽

Soil Conditions ◽

Effective Pressure ◽

Long Distance ◽

Splash Erosion ◽

Rain Drops ◽

Artificial Rain ◽

The Impact

To the article the results of the theoretical and experimental researches are given on questions of estimates of the dynamic rate effect of raindrop impact on soil. The aim of this work was to analyze the current methods to determine the rate of artificial rain pressure on the soil for the assessment of splash erosion. There are the developed author’s method for calculation the pressure of artificial rain on the soil and the assessment of splash erosion. The study aims to the justification of evaluation methods and the obtaining of quantitative characteristics, prevention and elimination of accelerated (anthropogenic) erosion, the creation and the realization of the required erosion control measures. The paper considers the question of determining the pressure of artificial rain on the soil. At the moment of raindrops impact, there is the tension in the soil, which is called vertical effective pressure. It is noted that the impact of rain drops in the soil there are stresses called vertical effective pressure. The equation for calculation of vertical effective pressure is proposed in this study using the known spectrum of raindrops. Effective pressure was 1.4 Pa for the artificial rain by sprinkler machine «Fregat» and 5.9 Pa for long distance sprinkler DD-30. The article deals with a block diagram of the sequence for determining the effective pressure of rain drops on the soil. This diagram was created by the author’s method of calculation of the effective pressure of rain drops on the soil. The need for an integrated approach to the description of the artificial rain impact on the soil is noted. Various parameters characterizing drop erosion are considered. There are data about the mass of splashed soil in the irrigation of various irrigation machinery and installations. For example, the rate (mass) of splashed soil was 0.28…0.78 t/ha under irrigation sprinkler apparatus RACO 4260–55/701C in the conditions of the Ryazan region. The method allows examining the environmental impact of sprinkler techniques for analyzes of the pressure, caused by raindrops, on the soil. It can also be useful in determining the irrigation rate before the runoff for different types of sprinkler equipment and soil conditions.

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DISCRESSION OF THE SAMPLE RESORTS POLICE IN THE IMPLEMENTATION OF ADMINISTRATIVE LAW PERSPECTIVE INVESTIGATION

Legal Standing Jurnal Ilmu Hukum ◽

10.24269/ls.v4i2.3065 ◽

2020 ◽

Vol 4 (2) ◽

pp. 147

Author(s):

Tamrin Muchsin ◽

Sri Sudono Saliro ◽

Nahot Tua Parlindungan Sihaloho ◽

Sardjana Orba Manullang

Keyword(s):

Empirical Research ◽

Qualitative Method ◽

Government Regulation ◽

Sampling Technique ◽

Administrative Law ◽

Criminal Investigation ◽

Accurate Data ◽

Long Distance ◽

The Impact ◽

Depth Interviews

It is still found that investigating officers do not have an S1 degree or equivalent in thejurisdiction of the Sambass Resort Police as mandated in PP No. 58 of 2010 concerningAmendments to Government Regulation Number 27 of 1983 concerning theImplementation of KUHAP article 2A paragraph (1) letter a. If the requirements ofinvestigators are not fulfilled, there will automatically be limits of authority, includingthe inability to issue investigation orders, detention warrants and other administrativeletters. This study used a qualitative method with juridical empirical research. Toobtain accurate data, purposive sampling technique was used, and primary datacollection by conducting in-depth interviews. The research results found, among others:first, discretion regarding the administration of investigations in the jurisdiction of theSambas Resort Police for the Sambas District Police who do not have investigatingofficers who meet the requirements, is then taken over by the Head of the CriminalInvestigation Unit as the supervisor of the integrated criminal investigation function.Second, the impact of an integrated investigation administration causes the time tocarry out investigations to be slow due to the long distance between the Sector Policeand the Resort Police.

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45. Education at distance: Broadcasting ECG rounds to Southeastern Ontario (BESO Project). An innovative approach for teaching electrocardiography

Clinical & Investigative Medicine ◽

10.25011/cim.v30i4.2805 ◽

2007 ◽

Vol 30 (4) ◽

pp. 51 ◽

Cited By ~ 2

Author(s):

A. Baranchuk ◽

G. Dagnone ◽

P. Fowler ◽

M. N. Harrison ◽

L. Lisnevskaia ◽

...

Keyword(s):

Health Care ◽

Real Time ◽

Digital Signal ◽

Teaching Methodology ◽

Care Providers ◽

Long Distance ◽

Medicine Clerkship ◽

Time Problem ◽

The Impact ◽

Ecg Interpretation

Electrocardiography (ECG) interpretation is an essential skill for physicians as well as for many other health care professionals. Continuing education is necessary to maintain these skills. The process of teaching and learning ECG interpretation is complex and involves both deductive mechanisms and recognition of patterns for different clinical situations (“pattern recognition”). The successful methodologies of interactive sessions and real time problem based learning have never been evaluated with a long distance education model. To evaluate the efficacy of broadcasting ECG rounds to different hospitals in the Southeastern Ontario region; to perform qualitative research to determine the impact of this methodology in developing and maintaining skills in ECG interpretation. ECG rounds are held weekly at Kingston General Hospital and will be transmitted live to Napanee, Belleville, Oshawa, Peterborough and Brockville. The teaching methodology is based on real ECG cases. The audience is invited to analyze the ECG case and the coordinator will introduce comments to guide the case through the proper algorithm. Final interpretation will be achieved emphasizing the deductive process and the relevance of each case. An evaluation will be filled out by each participant at the end of each session. Videoconferencing works through a vast array of internet LANs, WANs, ISDN phone lines, routers, switches, firewalls and Codecs (Coder/Decoder) and bridges. A videoconference Codec takes the analog audio and video signal codes and compresses it into a digital signal and transmits that digital signal to another Codec where the signal is decompressed and retranslated back into analog video and audio. This compression and decompression allows large amounts of data to be transferred across a network at close to real time (384 kbps with 30 frames of video per second). Videoconferencing communication works on voice activation so whichever site is speaking has the floor and is seen by all the participating sites. A continuous presence mode allows each site to have the same visual and audio involvement as the host site. A bridged multipoint can connect between 8 and 12 sites simultaneously. This innovative methodology for teaching ECG will facilitate access to developing and maintaining skills in ECG interpretation for a large number of health care providers. Bertsch TF, Callas PW, Rubin A. Effectiveness of lectures attended via interactive video conferencing versus in-person in preparing third-year internal medicine clerkship students for clinical practice examinations. Teach Learn Med 2007; 19(1):4-8. Yellowlees PM, Hogarth M, Hilty DM. The importance of distributed broadband networks to academic biomedical research and education programs. Acad Psychaitry 2006;30:451-455

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The Effect of Repeated Whole-Body Cryotherapy on Sirt1 and Sirt3 Concentrations and Oxidative Status in Older and Young Men Performing Different Levels of Physical Activity

Antioxidants ◽

10.3390/antiox10010037 ◽

2020 ◽

Vol 10 (1) ◽

pp. 37

Author(s):

Gabriela Wojciak ◽

Jadwiga Szymura ◽

Zbigniew Szygula ◽

Joanna Gradek ◽

Magdalena Wiecek

Keyword(s):

Physical Activity ◽

Young Men ◽

Oxidative Status ◽

Whole Body ◽

Stress Index ◽

Blood Levels ◽

Long Distance ◽

Antioxidant Defence ◽

Whole Body Cryotherapy ◽

The Impact

Background: The activity of antioxidant enzymes and sirtuins (Sirt) decreases along with age, which is counteracted by aerobic training. Sirtuins increase antioxidant defence. Whole-body cryotherapy (WBC) increases total antioxidant capacity (TAC) in young men. The aim of our study was to assess the impact of 24 WBC treatments on the blood concentration of selected sirtuins and the level of antioxidant defence as well as oxidative stress index of training and non-training men depending on age. Methods: The study involved 40 males. In each group, there were 10 non-training older and young men (60 NTR and 20 NTR), and 10 older and young long-distance runners (60 TR, 20 TR). During an 8-week period, participants underwent 24 WBC treatments (3 min −130 °C), which were performed three times a week (Monday, Wednesday, Friday). The concentrations of Sirt1, Sirt3, TAC, total oxidative status and the activity of superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) in the blood were determined before 1 WBC and after 1 WBC, 12 WBC and 24 WBC. Results: After 1 WBC, the activity of GPx and the concentration of Sirt1 and TAC in 60 TR and TAC in 60 NTR increased. After 12 WBC, the level of Sirt1 in 20 NTR and SOD in 20 TR increased. After 24 WBC, the level of Sirt1 increased in 60 TR and in 20 NTR, Sirt3 in 60 TR and SOD in 20 TR. Conclusions: Cryogenic temperatures increase blood levels of Sirt1 and Sirt3 and systemic antioxidant defence in men, but the effect is dependent on age, level of performed physical activity and the number of applied treatments.

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