Quantifying proximity, confinement, and interventions in disease outbreaks: a decision support framework for air-transported pathogens

The inability to communicate how infectious diseases are transmitted in human environments has triggered avoidance of interactions during the COVID-19 pandemic. We define a metric, Effective ReBreathed Volume (ERBV), that encapsulates how infectious pathogens transport in air. This measure distinguishes environmental transport from other factors in the chain of infection, thus allowing quantitative comparisons of the riskiness of different situations for any pathogens transported in air, including SARS-CoV-2. Particle size is a key factor in transport, removal onto surfaces, and elimination by mitigation measures, so ERBV is presented for a range of exhaled particle diameters: 1 μm, 10 μm, and 100 μm. Pathogen transport is enhanced by two separate but interacting effects: proximity and confinement. Confinement in enclosed spaces overwhelms proximity after 10-15 minutes for all but the largest particles. Therefore, we review plausible strategies to reduce the confinement effect. Changes in standard ventilation and filtration can reduce person-to-person transport of 1-μm particles (ERBV1) by 13-85% in residential and commercial situations. Deposition to surfaces competes with intentional removal for 10-μm and 100-μm particles, so the same interventions reduce ERBV10 by only 3-50%, and ERBV100 is unaffected. Determining transmission modes is critical to identify intervention effectiveness, and would be accelerated with prior knowledge of ERBV. When judiciously selected, the interventions examined can provide substantial reduction in risk, and the conditions for selection are identified. The framework of size-dependent ERBV supports analysis and mitigation decisions in an emerging situation, even before other infectious parameters are well known.

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Quantifying Proximity, Confinement, and Interventions in Disease Outbreaks: A Decision Support Framework for Air-Transported Pathogens

Environmental Science & Technology ◽

10.1021/acs.est.0c07721 ◽

2021 ◽

Vol 55 (5) ◽

pp. 2890-2898 ◽

Cited By ~ 1

Author(s):

Tami C. Bond ◽

Angela Bosco-Lauth ◽

Delphine K. Farmer ◽

Paul W. Francisco ◽

Jeffrey R. Pierce ◽

...

Keyword(s):

Decision Support ◽

Disease Outbreaks ◽

Decision Support Framework

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Dynamics of host populations affected by the emerging fungal pathogen Batrachochytrium salamandrivorans

Royal Society Open Science ◽

10.1098/rsos.160801 ◽

2017 ◽

Vol 4 (3) ◽

pp. 160801 ◽

Cited By ~ 16

Author(s):

Benedikt R. Schmidt ◽

Claudio Bozzuto ◽

Stefan Lötters ◽

Sebastian Steinfartz

Keyword(s):

Emerging Infectious Diseases ◽

Disease Outbreaks ◽

Host Population ◽

Mitigation Measures ◽

Disease Emergence ◽

Batrachochytrium Salamandrivorans ◽

In The Wild ◽

Successful Control ◽

Using Data ◽

Local Extirpation

Emerging infectious diseases cause extirpation of wildlife populations. We use an epidemiological model to explore the effects of a recently emerged disease caused by the salamander-killing chytrid fungus Batrachochytrium salamandrivorans ( Bsal ) on host populations, and to evaluate which mitigation measures are most likely to succeed. As individuals do not recover from Bsal , we used a model with the states susceptible, latent and infectious, and parametrized the model using data on host and pathogen taken from the literature and expert opinion. The model suggested that disease outbreaks can occur at very low host densities (one female per hectare). This density is far lower than host densities in the wild. Therefore, all naturally occurring populations are at risk. Bsal can lead to the local extirpation of the host population within a few months. Disease outbreaks are likely to fade out quickly. A spatial variant of the model showed that the pathogen could potentially spread rapidly. As disease mitigation during outbreaks is unlikely to be successful, control efforts should focus on preventing disease emergence and transmission between populations. Thus, this emerging wildlife disease is best controlled through prevention rather than subsequent actions.

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Social distancing in America: Understanding long-term adherence to COVID-19 mitigation recommendations

PLoS ONE ◽

10.1371/journal.pone.0257945 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0257945

Author(s):

Christopher P. Reinders Folmer ◽

Megan A. Brownlee ◽

Adam D. Fine ◽

Emmeke B. Kooistra ◽

Malouke E. Kuiper ◽

...

Keyword(s):

Social Norms ◽

Disease Outbreaks ◽

The United States ◽

Mitigation Measures ◽

Personal Factors ◽

Cross Sectional ◽

Social Distancing ◽

Infectious Disease Outbreaks ◽

Practical Capacity ◽

Major Factors

A crucial question in the governance of infectious disease outbreaks is how to ensure that people continue to adhere to mitigation measures for the longer duration. The present paper examines this question by means of a set of cross-sectional studies conducted in the United States during the COVID-19 pandemic, in May, June, and July of 2020. Using stratified samples that mimic the demographic characteristics of the U.S. population, it seeks to understand to what extent Americans continued to adhere to social distancing measures in the period after the first lockdown ended. Moreover, it seeks to uncover which variables sustained (or undermined) adherence across this period. For this purpose, we examined a broad range of factors, relating to people’s (1) knowledge and understanding of the mitigation measures, (2) perceptions of their costs and benefits, (3) perceptions of legitimacy and procedural justice, (4) personal factors, (5) social environment, and (6) practical circumstances. Our findings reveal that adherence was chiefly shaped by three major factors: respondents adhered more when they (a) had greater practical capacity to adhere, (b) morally agreed more with the measures, and (c) perceived the virus as a more severe health threat. Adherence was shaped to a lesser extent by impulsivity, knowledge of social distancing measures, opportunities for violating, personal costs, and descriptive social norms. The results also reveal, however, that adherence declined across this period, which was partly explained by changes in people’s moral alignment, threat perceptions, knowledge, and perceived social norms. These findings show that adherence originates from a broad range of factors that develop dynamically across time. Practically these insights help to improve pandemic governance, as well as contributing theoretically to the study of compliance and the way that rules come to shape behavior.

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ENER-BI: Integrating Energy and Spatial Data for Cities’ Decarbonisation Planning

Sustainability ◽

10.3390/su13010383 ◽

2021 ◽

Vol 13 (1) ◽

pp. 383

Author(s):

Koldo Urrutia-Azcona ◽

Elena Usobiaga-Ferrer ◽

Pablo De Agustín-Camacho ◽

Patricia Molina-Costa ◽

Mauricia Benedito-Bordonau ◽

...

Keyword(s):

Spatial Data ◽

Local Level ◽

Spatial Dimension ◽

Urban Environments ◽

Mitigation Measures ◽

City Managers ◽

Whole Process ◽

Digital Era ◽

Key Factor ◽

Urban Energy

Given the current climate emergency, our planet is suffering. Mitigation measures must be urgently deployed in urban environments, which are responsible for more than 70% of global CO2 emissions. In this sense, a deeper integration between energy and urban planning disciplines is a key factor for effective decarbonisation in urban environments. This is addressed in the Cities4ZERO decarbonisation methodology. This method specifically points out the need for technology-based solutions able to support that integration among both disciplines at a local level, enriching decision-making in urban decarbonisation policy-making, diagnosis, planning, and follow-up tasks, incorporating the spatial dimension to the whole process (GIS-based), as well as the possibilities of the digital era. Accordingly, this paper explores the demands of both integrated urban energy planning and European/Basque energy directives, to set the main requisites and functionalities that Decision Support Systems (DSSs) must fulfil to effectively support city managers and the urban decarbonisation process.

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Impact of COVID-19 Mitigation Measures on Mosquito-Borne Diseases in 2020 in Queensland, Australia

Viruses ◽

10.3390/v13061150 ◽

2021 ◽

Vol 13 (6) ◽

pp. 1150

Author(s):

Cassie C. Jansen ◽

Jonathan M. Darbro ◽

Frances A. Birrell ◽

Martin A. Shivas ◽

Andrew F. van den Hurk

Keyword(s):

Substantial Reduction ◽

Human Movement ◽

Mitigation Measures ◽

Protective Measures ◽

Disease Epidemiology ◽

Increased Risk ◽

Risk Of Exposure ◽

Precipitous Decline ◽

And Control ◽

The Impact

We describe the impact of COVID-19 mitigation measures on mosquito-borne diseases in Queensland, Australia, during the first half of 2020. Implementation of restrictions coincided with an atypical late season outbreak of Ross River virus (RRV) characterized by a peak in notifications in April (1173) and May (955) which were greater than 3-fold the mean observed for the previous four years. We propose that limitations on human movement likely resulted in the majority of RRV infections being acquired at or near the place of residence, and that an increase in outdoor activities, such as gardening and bushwalking in the local household vicinity, increased risk of exposure to RRV-infected mosquitoes. In contrast, the precipitous decline in international passenger flights led to a reduction in the number of imported dengue and malaria cases of over 70% and 60%, respectively, compared with the previous five years. This substantial reduction in flights also reduced a risk pathway for importation of exotic mosquitoes, but the risk posed by importation via sea cargo was not affected. Overall, the emergence of COVID-19 has had a varied impact on mosquito-borne disease epidemiology in Queensland, but the need for mosquito surveillance and control, together with encouragement of personal protective measures, remains unchanged.

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A Potential Mitigation Measure of the Seismic Distress of the Circuit Wall at the Acropolis of Athens

10.21203/rs.3.rs-486935/v1 ◽

2021 ◽

Author(s):

Manolis Katsirakis ◽

Yiannis Tsompanakis ◽

Prodromos N. Psarropoulos

Keyword(s):

Seismic Vulnerability ◽

Substantial Reduction ◽

Earth Pressure ◽

Element Model ◽

Expanded Polystyrene ◽

Mitigation Measures ◽

Retaining Structures ◽

Mitigation Measure ◽

Entire Height ◽

Before And After

Abstract The seismic design of new retaining structures is usually performed following modern seismic norms. Nonetheless, there are various monumental retaining structures (e.g., fortifications) with high seismic vulnerability, which must be protected against earthquakes, while there are several limitations on the type of mitigation measures that can be applied to such cultural heritage structures. The present study investigates numerically the seismic response and distress of the Circuit Wall of the Athenian Acropolis. The Wall is a monumental masonry retaining structure surrounding the world-class monuments of the archeological hill of the Acropolis. Given the fact that the wider region of Athens is characterized by moderate to high seismicity, it is necessary to protect the Wall from strong ground motions. For this purpose, the geological, seismological, and topographic conditions of the Acropolis hill, as well as the geometry and the mechanical properties of the Wall, are realistically taken into account. A representative finite-element model has been developed for a critical section of the Wall, which has been validated with available records from accelerometers being installed at the Wall. Subsequently, an efficient and suitable -according to international monument restoration guidelines- seismic mitigation measure is proposed. The results of dynamic earth-pressure distribution on the Wall are presented before and after the application of expanded polystyrene (EPS) blocks behind the Wall. Α detailed parametric study illustrates a substantial reduction of dynamic pressures on the Wall when the EPS blocks are applied, either along the entire height or only at the lower part of the Wall.

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Social Distancing in America: Understanding Long-term Adherence to Covid-19 Mitigation Recommendations

10.31234/osf.io/457em ◽

2020 ◽

Author(s):

Christopher Reinders Folmer ◽

Megan Brownlee ◽

Adam Fine ◽

Malouke Esra Kuiper ◽

Elke Olthuis ◽

...

Keyword(s):

Disease Outbreaks ◽

The United States ◽

Mitigation Measures ◽

Cross Sectional ◽

Situational Influences ◽

Social Distancing ◽

Short Period ◽

Practical Capacity ◽

Nationally Representative ◽

Motivational Influences

A crucial question in the governance of infectious disease outbreaks is how to ensure that people continue to adhere to mitigation measures for the longer duration of the pandemic. The present paper examines this question by means of a nationally representative cross-sectional set of studies conducted in the United States in May, June, and July 2020. It seeks to understand to what extent Americans continued to adhere to social distancing measures in the period after the first lockdown ended during the first wave of COVID-19. Moreover, it seeks to uncover which situational and motivational variables sustained (or undermined) adherence. Our findings reveal a mix of situational and motivational variables that contributed to adherence in the period after the first lockdown: individuals’ knowledge of social distancing measures, their practical capacity to adhere to them, their opportunities for not doing so, and their impulsivity (situational influences), as well as their moral alignment with mitigation measures against the virus, perceptions of its health threat, and perceived norms for adherence in their community (motivational influences). The results also reveal, however, that adherence among Americans declined during this period, as did important situational and motivational processes that sustained this. The findings show that adherence does not just originate in motivations and that situational variables play a central role. Moreover, they show that adherence is dynamic, as the core variables that sustain can change over a short period of time. These insights help to advance understanding of pandemic governance, as well as illuminating the interaction between rules and human conduct and compliance more generally. Moreover, they identify important avenues for policy to promote and sustain adherence to mitigation measures during the COVID-19 pandemic and in future outbreaks.

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Novel Erosion Control Technology for Production Debottlenecking

Volume 5: Pipelines, Risers, and Subsea Systems ◽

10.1115/omae2018-78033 ◽

2018 ◽

Author(s):

Prasad Laxman Kane ◽

Dominic Pliszka

Keyword(s):

Substantial Reduction ◽

Erosion Control ◽

Significant Loss ◽

Mitigation Measures ◽

Control Technology ◽

Product Flow ◽

Sand Erosion ◽

Piping Systems ◽

Global And Local ◽

The Impact

Erosion of piping systems is a significant issue for many operators of Hydrocarbon infrastructure. Until now mitigation measures have been limited to detection / measurement and reducing production. For many operators this can be a significant loss in revenue and an increase in IMR costs. A novel Erosion Control Technology (ECT) is being developed that can significantly reduce the impact of erosion on piping infrastructure. This technology has the potential of adding immense value when it is used to debottleneck and optimize flow rates. The patented ECT has been designed to control sand erosion in real-time by deflecting and redistributing sand in the product flow stream. Preliminary laboratory testing of the ECT has been very successful. The ECT inserts designed for the ambient test conditions have shown substantial reduction in erosion (both global and local). Computational Fluid Dynamics (CFD) has been the key enabling factor allowing the critical breakthrough in this technology. Experimental results have shown very good correlation with the CFD sand erosion model results. A roadmap in line with industry practices and standards has been developed for project implementation of the ECT solution in the near future.

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Suspicious minds: cinematic depiction of distrust during epidemic disease outbreaks

Medical Humanities ◽

10.1136/medhum-2020-011871 ◽

2020 ◽

pp. medhum-2020-011871 ◽

Cited By ~ 1

Author(s):

Qijun Han ◽

Daniel R Curtis

Keyword(s):

Popular Culture ◽

Disease Transmission ◽

Disease Outbreaks ◽

Epidemic Disease ◽

Social Responses ◽

News Reporting ◽

Television Shows ◽

Social Controls ◽

Key Factor ◽

Key Issues

One key factor that appears to be crucial in the rejection of quarantines, isolation and other social controls during epidemic outbreaks is trust—or rather distrust. Much like news reporting and social media, popular culture such as fictional novels, television shows and films can influence people’s trust, especially given that the information provided about an epidemic disease is sometimes seen as grounded in ‘scientific fact’ by societies. As well as providing information on the ‘correct science’ behind disease transmission, spread and illness in films and literature, popular culture can also inform societies about how to feel and how to react during epidemics—that is to say create some expectations about the kinds of societal responses that could potentially occur. In this article we closely analyse three films that centre around epidemic diseases—Contagion (Steven Soderbergh, 2011), Blindness (Fernando Meirelles, 2008) and The Painted Veil (John Curran, 2006)—in order to highlight three categories of distrust that have recently been identified and conceptualised in broader discussions regarding trust and health: institutional, social and interpersonal. These films raise two key issues about trust and social responses during epidemics. First, while certain aspects of trust are badly diminished during epidemic disease outbreaks, epidemics can also interact with pre-existing structural inequalities within society—based on race, gender or wealth—to create mixed outcomes of discord, prejudice and fear that coexist with new forms of cohesion. Second, the breakdown in trust seen at certain levels during epidemics, such as at the institutional level between communities and authorities or elites, might be mediated or negotiated, perhaps even compensated for, by heightened solidity of trust at the social level, within or between communities.

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Size-dependent foraging of larval Atlantic cod (Gadus morhua)

Canadian Journal of Zoology ◽

10.1139/z04-114 ◽

2004 ◽

Vol 82 (8) ◽

pp. 1380-1389 ◽

Cited By ~ 17

Author(s):

Velmurugu Puvanendran ◽

Karine Salies ◽

Benjamin Laurel ◽

Joseph A Brown

Keyword(s):

Marine Fish ◽

Gadus Morhua ◽

Atlantic Cod ◽

Prey Selection ◽

Fish Larvae ◽

Growth And Survival ◽

Size Dependent ◽

Marine Fish Larvae ◽

Key Factor ◽

Foraging Environment

Most marine fish larvae are thought to be gape-limited predators, and the presence of suitably sized prey at the appropriate time in the foraging environment is a key factor for their growth and survival. Two experiments were carried out: in experiment 1, we investigated feeding of Atlantic cod (Gadus morhua L., 1758) larvae from 5 to 35 days post hatch on prey of three different sizes: two different-sized strains of rotifers, small rotifers (SR) and large rotifers (LR), and Artemia Leach, 1819 nauplii (AN), or an equal mixture of the three types of prey (MIX). In experiment 2, cod larvae were fed SR, LR, or a combination of SR and LR (MIX-R) at concentrations of 1500 and 4000 prey·L–1 from 4 to 20 days post hatch. Feeding incidence, number of prey in the gut, mouth gape, and prey selection were measured. In experiment 1, feeding incidence was initially higher in the SR treatment, while larvae failed to start feeding in either the LR or the AN treatment at 5 dph. Larvae in the LR treatment started feeding at 8 dph, and feeding incidence was comparable to that in the SR treatment, but the total number of prey eaten was higher in the SR than in the LR treatment until 20 dph. Larvae did not start feeding on AN until 26 dph, although they attacked them from 5 dph. In the MIX-R treatment in experiment 2, larvae fed selectively on LR at 4000 prey·L–1, whereas no selection was observed at 1500 prey·L–1. Our results suggest that cod larvae are gape-limited predators and the concentration of prey affects prey selection.

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