A model based on a high-resolution flux matrix explains the spread of diseases in a spatial network and the effect of mitigation strategies

Propagation of an epidemic across a spatial network of communities is described by a variant of the SIR model accompanied by an intercommunity infectivity matrix. This matrix is estimated from fluxes between communities, obtained from cell-phone tracking data recorded in the USA between March 2020 and February 2021. We have applied this model to the 2020 dynamics of the SARS-CoV-2 pandemic. We find that the numbers of susceptible and infected individuals predicted by the model agree with the reported cases in each community by fitting just one global parameter representing the frequency of interaction between individuals. The effect of "shelter-in-place" policies introduced across the USA at the onset of the pandemic is clearly seen in our results. We then consider the effect that alternative policies would have had, namely restricting long-range travel. We find that this policy is successful in decreasing the epidemic size and slowing down the spread, at the expense of a substantial restriction on mobility as a function of distance. When long-distance mobility is suppressed, this policy results in a traveling wave of infections, which we characterize analytically. In particular, we show the dependence of the wave velocity and profile on the transmission parameters. Finally, we discuss a policy of selectively constraining travel based on an edge-betweenness criterion.

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Making Connections: The Long-Distance Bus Industry in the USA. ByMargaret Walsh, xvii + 245 pp. Aldershot, U.K.: Ashgate, 2000. Index, notes, bibliography, illustrations, tables. Cloth, $74.95. ISBN 0–754–60207–9.

The Business History Review ◽

10.2307/4127723 ◽

2002 ◽

Vol 76 (4) ◽

pp. 876-878

Author(s):

Owen D. Gutfreund

Keyword(s):

Long Distance ◽

The Usa

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COVID-TRACK: world and USA SARS-COV-2 testing and COVID-19 tracking

BioData Mining ◽

10.1186/s13040-021-00233-2 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Ye Emma Zohner ◽

Jeffrey S. Morris

Keyword(s):

Web Application ◽

The United States ◽

Mitigation Strategies ◽

Time Lags ◽

Policy Makers ◽

Major Health ◽

Dynamic Representation ◽

Graphical Displays ◽

The Usa ◽

User Friendly

Abstract Background The COVID-19 pandemic has caused major health and socio-economic disruptions worldwide. Accurate investigation of emerging data is crucial to inform policy makers as they construct viral mitigation strategies. Complications such as variable testing rates and time lags in counting cases, hospitalizations and deaths make it challenging to accurately track and identify true infectious surges from available data, and requires a multi-modal approach that simultaneously considers testing, incidence, hospitalizations, and deaths. Although many websites and applications report a subset of these data, none of them provide graphical displays capable of comparing different states or countries on all these measures as well as various useful quantities derived from them. Here we introduce a freely available dynamic representation tool, COVID-TRACK, that allows the user to simultaneously assess time trends in these measures and compare various states or countries, equipping them with a tool to investigate the potential effects of the different mitigation strategies and timelines used by various jurisdictions. Findings COVID-TRACK is a Python based web-application that provides a platform for tracking testing, incidence, hospitalizations, and deaths related to COVID-19 along with various derived quantities. Our application makes the comparison across states in the USA and countries in the world easy to explore, with useful transformation options including per capita, log scale, and/or moving averages. We illustrate its use by assessing various viral trends in the USA and Europe. Conclusion The COVID-TRACK web-application is a user-friendly analytical tool to compare data and trends related to the COVID-19 pandemic across areas in the United States and worldwide. Our tracking tool provides a unique platform where trends can be monitored across geographical areas in the coming months to watch how the pandemic waxes and wanes over time at different locations around the USA and the globe.

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Drought spatiotemporal propagation via land feedbacks

10.5194/egusphere-egu21-1505 ◽

2021 ◽

Author(s):

Diego G. Miralles ◽

Dominik L. Schumacher ◽

Jessica Keune ◽

Paul A. Dirmeyer

Keyword(s):

Soil Moisture ◽

Water Vapor ◽

Mitigation Strategies ◽

Soil Drought ◽

The Usa ◽

Forecast Models ◽

Atmospheric Feedbacks ◽

Dry Out ◽

Water And Food Security ◽

The Impact

The predicted increase in drought occurrence and intensity will pose serious threats to global future water and food security. This was hinted by several historically unprecedented droughts over the last two decades, taking place in Europe, Australia, Amazonia or the USA. It has been hypothesised that the strength of these events responded to self-reinforcement processes related to land&#8211;atmospheric feedbacks: as rainfall deficits dry out soil and vegetation, the evaporation of land water is reduced, then the local air becomes too dry to yield rainfall, which further enhances drought conditions. Despite the 'local' nature of these feedbacks, their consequences can be remote, as downwind regions may rely on evaporated water transported by winds from drought-affected locations. Following this rationale, droughts may not only self-reinforce locally, due to land atmospheric feedbacks, but self-propagate in the downwind direction, always conditioned on atmospheric circulation. This propagation is not only meteorological but relies on soil moisture drought, and may lead to a downwind cascading of impacts on water resources. However, a global capacity to observe these processes is lacking, and thus our knowledge of how droughts start and evolve, and how this may change as climate changes, remains limited. Furthermore, climate and forecast models are still immature when it comes to representing the influences of land on rainfall.Here, the largest global drought events are studied to unravel the role of land&#8211;atmosphere feedbacks during the spatiotemporal propagation of these events. We based our study on satellite and reanalysis records of soil moisture, evaporation, air humidity, winds and precipitation, in combination with a Lagrangian framework that can map water vapor trajectories and explore multi-dimensional feedbacks. We estimate the reduction in precipitation in the direction of drought propagation that is caused by the upwind soil moisture drought, and isolate this effect from the influence of potential evaporation and circulation changes. By doing so, the downwind lack of precipitation caused by upwind soil drought via water vapor deficits, and hence the impact of drought self-propagation, is determined. We show that droughts occurring in dryland regions are particularly prone to self-propagate, as evaporation there tends to respond strongly to enhanced soil stress and precipitation is frequently convective. This kind of knowledge may be used to improve climate and forecast models and can be exploited to develop geo-engineering mitigation strategies to help prevent drought events from aggravating during their early stages.

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Tomato yellow leaf curl virus (leaf curl).

10.1079/cpc.55402.20210104831 ◽

2021 ◽

Author(s):

Henryk Czosnek

Keyword(s):

Middle Eastern ◽

Long Distance ◽

Tomato Production ◽

Tomato Seedlings ◽

Caribbean Islands ◽

The Usa ◽

History Of ◽

Leaf Curl Virus ◽

Whitefly Vector ◽

Leaf Curl

Abstract The wide global distribution of tomato crops and the dramatic outbreaks of the populations of the TYLCV vector, the whitefly Bemisia tabaci, led to a pandemic of this devastating disease. The virus probably arose in the Middle East between the 1930s and 1950s. Its global invasion began in the 1980s after the emergence of two strains: TYLCV-IL and TYLCV-Mld. The long-distance transportation of viruliferous whiteflies contaminating commercial shipments of tomato seedlings and ornamentals is probably the major reason for the virus pandemic (Caciagli, 2007). Sequence analyses allowed Lefeuvre et al. (2010) to trace the history of TYLCV spread. For instance, TYLCV-IL has invaded the Americas at least twice, once from the Mediterranean basin in 1992-1994 and once from Asia (a descendant of imported Middle Eastern TYLCV) in 1999-2003. As a result the estimated losses caused by TYLCV reached about 20% of tomato production in the USA, and 30-100% in the Caribbean Islands, Mexico, Central America and Venezuela. Therefore several countries (Australia, EU) have established severe quarantine measures to control the whitefly vector.

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Modelling Excess Mortality in Covid-19-Like Epidemics

Entropy ◽

10.3390/e22111236 ◽

2020 ◽

Vol 22 (11) ◽

pp. 1236

Author(s):

Zdzislaw Burda

Keyword(s):

Disease Transmission ◽

Mitigation Strategies ◽

System Capacity ◽

Infectious Period ◽

Cumulative Number ◽

Epidemic Spreading ◽

Social Contacts ◽

Local Modes ◽

Hybrid Strategy ◽

The Usa

We develop an agent-based model to assess the cumulative number of deaths during hypothetical Covid-19-like epidemics for various non-pharmaceutical intervention strategies. The model simulates three interrelated stochastic processes: epidemic spreading, availability of respiratory ventilators and changes in death statistics. We consider local and non-local modes of disease transmission. The first simulates transmission through social contacts in the vicinity of the place of residence while the second through social contacts in public places: schools, hospitals, airports, etc., where many people meet, who live in remote geographic locations. Epidemic spreading is modelled as a discrete-time stochastic process on random geometric networks. We use the Monte–Carlo method in the simulations. The following assumptions are made. The basic reproduction number is R0=2.5 and the infectious period lasts approximately ten days. Infections lead to severe acute respiratory syndrome in about one percent of cases, which are likely to lead to respiratory default and death, unless the patient receives an appropriate medical treatment. The healthcare system capacity is simulated by the availability of respiratory ventilators or intensive care beds. Some parameters of the model, like mortality rates or the number of respiratory ventilators per 100,000 inhabitants, are chosen to simulate the real values for the USA and Poland. In the simulations we compare ‘do-nothing’ strategy with mitigation strategies based on social distancing and reducing social mixing. We study epidemics in the pre-vacine era, where immunity is obtained only by infection. The model applies only to epidemics for which reinfections are rare and can be neglected. The results of the simulations show that strategies that slow the development of an epidemic too much in the early stages do not significantly reduce the overall number of deaths in the long term, but increase the duration of the epidemic. In particular, a hybrid strategy where lockdown is held for some time and is then completely released, is inefficient.

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Climate change advocacy: exploring links between student empowerment and civic engagement

International Journal of Sustainability in Higher Education ◽

10.1108/ijshe-03-2020-0091 ◽

2020 ◽

Vol 21 (6) ◽

pp. 1209-1231

Author(s):

Alicia B. Wodika ◽

Wendi K. Middleton

Keyword(s):

Climate Change ◽

Service Learning ◽

Data Collection ◽

Civic Engagement ◽

Climate Change Adaptation ◽

Mitigation Strategies ◽

Student Experiences ◽

Content Type ◽

The Usa ◽

Adaptation And Mitigation

Purpose This study identified the attitudes and behaviors of college students regarding their advocacy for climate change adaptation and mitigation. Specifically, perceptions of climate change were assessed and advocacy activities were identified for climate change and/or other topics. Design/methodology/approach Using convenience sampling, students (n = 440) from three universities in the Midwest, the USA, completed surveys assessing their level of agreement with activities related to civic engagement, climate change and policy. Semantic differential scales focused on “learning about climate change,” “advocating for climate change mitigation” and “advocating for climate change adaptation.” Three open-ended questions were used to identify student experiences with civic engagement and/or service-learning, as well as topics in which they advocate and how they advocate. Findings Regarding advocacy in general, over 50% of the sample did not advocate for any topic, with 24.5% of students stating they advocated for the environment/climate change. Students who identified as female, democratic and 1st or 2nd year in school were more likely to be engaged with environmental advocacy. Regarding civic engagement, seniors were more actively engaged with their communities and also more likely to vote in local, state and national elections. Research limitations/implications Time of data collection was a potential limitation with schools conducting data collection at different time periods. Students who identified more progressive politically were also more likely to participate in the study. Originality/value While research exists regarding student civic engagement levels, this research project identified ways in which students engaged in advocacy, identifying potential links with civic engagement and enhanced participation in climate change adaptation and mitigation strategies.

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Challenges of enforcing cell phone use while driving laws among police: a qualitative study

Injury Prevention ◽

10.1136/injuryprev-2018-042931 ◽

2018 ◽

Vol 25 (6) ◽

pp. 494-500 ◽

Cited By ~ 2

Author(s):

Toni Marie Rudisill ◽

Adam D Baus ◽

Traci Jarrett

Keyword(s):

Law Enforcement ◽

Perceived Risk ◽

Cell Phone ◽

Qualitative Content Analysis ◽

Qualitative Interviews ◽

Time Of Day ◽

Cultural Norms ◽

Law Enforcement Agencies ◽

Cell Phone Use ◽

The Usa

BackgroundCell phone use while driving laws do not appear to be heavily enforced in the USA. This study seeks to gain law enforcements’ perspective and learn potential barriers to cell phone law enforcement.MethodsQualitative interviews (ie, focus groups) were conducted with officers (N=19) from five West Virginia law enforcement agencies. The officers who participated were >18 years of age, sworn into their departments and employed in law enforcement for >1 year. Focus group sessions lasted 45–60 min and followed a standardised, pilot-tested script. These sessions were audio recorded and transcribed. Qualitative content analysis was employed among three researchers to determine themes surrounding enforcement.ResultsFour themes emerged including current culture, the legal system, the nature of police work and issues with prevention. Specific barriers to enforcement included cultural norms, lack of perceived support from courts/judges, different laws between states, the need for a general distracted driving law, unclear legislation, officers’ habits and perceived risk, wanting to maintain a positive relationship with the public, not being able to see the driver (impediments of vehicle design, time of day), phones having multiple functions and not knowing what drivers are actually doing, risk of crashing during traffic stops and lack of resources. Prevention activities were debated, and most felt that technological advancements implemented by cell phone manufacturers may deter use.ConclusionsNumerous barriers to cell phone law enforcement exist. Legislation could be amended to facilitate enforcement. Prevention opportunities exist to deter cell phone use while driving.

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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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The Alarm Center in Stockholm County Council

Prehospital and Disaster Medicine ◽

10.1017/s1049023x00044125 ◽

1985 ◽

Vol 1 (S1) ◽

pp. 131-132

Author(s):

Bo Brismar

Keyword(s):

Western Europe ◽

Medical Training ◽

County Council ◽

West Germany ◽

Long Distance ◽

Long Distance Transport ◽

The Usa ◽

Medical Transport ◽

Transportation Vehicle ◽

Distance Transport

During the last ten years, both in Western Europe and in the USA, the attitude towards medical transport activities has radically changed. From being a purely transportation vehicle the ambulance is now increasingly regarded as an extended arm of medical care. At the same time as ambulance crews have received more qualified medical training, the equipment of the ambulances themselves has been improved. In several countries such as the USA, France and West Germany, a differentiated ambulance organization has been built up, with specially equipped emergency ambulances manned by paramedics, and standard ambulances with emergency technicians for planned transports. During this time helicopters have been put into increasing use as a supplement to ambulances for emergency long distance transport to units such as trauma and burn centers.

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