Microbiome influence on host community dynamics: Conceptual integration of microbiome feedback with classical host–microbe theory

Purpose The purpose of this paper is to introduce this special issue about the “Impact of the Global Refugee Crisis on the Career Ecosystem” and summarise the key contributions of the included practitioner and scholarly papers which examine refugee business and labour market experiences. The paper also examines the impact of media reports to provide a broader understanding of the context within which the current refugee crisis is evolving. Design/methodology/approach The authors begin with a delineation of the concept of a career ecosystem in the context of refugee crises. The authors then employ this framing as a backdrop to engage in a basic analysis of business media coverage of the most recent Syrian refugee crisis, and a summary of the practitioner and scholarly papers. Findings The findings of the media analysis suggest major coverage differences between different groups of countries in the number of documents identified, the proposed aim of business engagement with refugees, and substance of the extracted statements generally. Research limitations/implications The analysis of business media coverage is rudimentary and intended only as a prompt for further conversations about how contemporary media commentary impacts on career opportunities for refugees and relevant stakeholder practices. Practical implications This paper demonstrates the importance of including broader considerations of refugee careers that explore the interaction and intersection with transnational and local ecosystem of labour markets while paying attention to the sociocultural and political refugee-host community dynamics. Originality/value This paper presents a more systems-oriented perspective and provides both practice and scholarly perspectives on the composite and dynamic nature of the refugee crisis on career ecosystems more broadly.

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Links between mouse and vole social networks and their gut microbiomes support predictions from metacommunity theory

10.1101/2020.08.18.256370 ◽

2020 ◽

Author(s):

Joël W. Jameson ◽

Steven W. Kembel ◽

Denis Réale

Keyword(s):

Social Networks ◽

Host Species ◽

Community Dynamics ◽

Peromyscus Maniculatus ◽

Interspecific Interactions ◽

Host Community ◽

Social Proximity ◽

Strongly Connected ◽

Bacterial Transmission

ABSTRACTMetacommunity theory predicts that strongly connected individuals will harbour similar gut microbiomes (GMs) and affiliating with more individuals should increase GM diversity. Additionally, cross-species bacterial transmission may play a role in how interspecific interactions affect host community dynamics. We tracked sympatric mice (Peromyscus maniculatus) and voles (Myodes gapperi) and constructed social networks for each species and both species together. We tested whether: 1) similarity in GM composition between individuals correlates with their social proximity within and across species; 2) GM diversity correlates with a host’s number of conspecific or heterospecific neighbours. We could not differentiate associations between GM composition and mouse social proximity or habitat. In voles, social proximity explained part of the GM composition. GM composition associated with interspecific social proximity, and mouse GM diversity correlated with number of vole neighbours. Contributions of host-host bacterial transmission to the GM partly follow metacommunity theory but depend on host species.

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Integrating Spatiotemporal Epidemiology, Eco-Phylogenetics, and Distributional Ecology to Assess West Nile Disease Risk in Horses

Viruses ◽

10.3390/v13091811 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1811

Author(s):

John M. Humphreys ◽

Angela M. Pelzel-McCluskey ◽

Lee W. Cohnstaedt ◽

Bethany L. McGregor ◽

Kathryn A. Hanley ◽

...

Keyword(s):

Community Dynamics ◽

Disease Risk ◽

Bird Species ◽

Integrated Approach ◽

The United States ◽

Host Community ◽

Avian Host ◽

West Nile ◽

Phylogenetic Structure ◽

Vaccination Programs

Mosquito-borne West Nile virus (WNV) is the causative agent of West Nile disease in humans, horses, and some bird species. Since the initial introduction of WNV to the United States (US), approximately 30,000 horses have been impacted by West Nile neurologic disease and hundreds of additional horses are infected each year. Research describing the drivers of West Nile disease in horses is greatly needed to better anticipate the spatial and temporal extent of disease risk, improve disease surveillance, and alleviate future economic impacts to the equine industry and private horse owners. To help meet this need, we integrated techniques from spatiotemporal epidemiology, eco-phylogenetics, and distributional ecology to assess West Nile disease risk in horses throughout the contiguous US. Our integrated approach considered horse abundance and virus exposure, vector and host distributions, and a variety of extrinsic climatic, socio-economic, and environmental risk factors. Birds are WNV reservoir hosts, and therefore we quantified avian host community dynamics across the continental US to show intra-annual variability in host phylogenetic structure and demonstrate host phylodiversity as a mechanism for virus amplification in time and virus dilution in space. We identified drought as a potential amplifier of virus transmission and demonstrated the importance of accounting for spatial non-stationarity when quantifying interaction between disease risk and meteorological influences such as temperature and precipitation. Our results delineated the timing and location of several areas at high risk of West Nile disease and can be used to prioritize vaccination programs and optimize virus surveillance and monitoring.

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Temporal variations in COVID-19: an epidemiological discussion with a practical application

Journal of International Medical Research ◽

10.1177/03000605211033208 ◽

2021 ◽

Vol 49 (8) ◽

pp. 030006052110332

Author(s):

Mahnaz Derakhshan ◽

Hamid Reza Ansarian ◽

Mory Ghomshei

Keyword(s):

Time Series ◽

Community Dynamics ◽

Control Strategies ◽

Case Fatality ◽

Temporal Variations ◽

Host Community ◽

Short Term ◽

Weekly Cycles ◽

And Control

Objective We aimed to characterize the temporal variation in coronavirus disease 2019 (COVID-19) infection and mortality as a possible tool to monitor and control the spread of this disease. Methods We analyzed cyclicity and synchronicity in cases of COVID-19 infection and time series of deaths using Fourier transform, its inverse method, and statistical treatments. Epidemiological indices (e.g., case fatality rate) were used to quantify the observations in the time series. The possible causes of short-term variations are reviewed. Results We observed that were both short-term and long-term variations in the COVID-19 time series. The short cycles were 7 days and synchronized among all countries. This periodicity is believed to be caused by weekly cycles in community social factors, combined with diagnostic and reporting cycles. This could also be related to virus–host–community dynamics. Conclusion The observed synchronized weekly cycles could serve as herd defense by providing a form of social distancing in time. The effect of such temporal distancing could be enhanced if combined with spatial distancing. Integrated spatiotemporal distancing is therefore recommended to optimize infection control strategies, taking into account the quiescent and active intervals of COVID-19.

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A mixed model approach for estimating drivers of microbiota community composition and differential taxonomic abundance

10.1101/2020.11.24.395715 ◽

2020 ◽

Author(s):

Amy R Sweeny ◽

Hannah Lemon ◽

Anan Ibrahim ◽

Daniel H Nussey ◽

Andrew Free ◽

...

Keyword(s):

Gut Microbiota ◽

Community Composition ◽

Community Dynamics ◽

Multiple Scales ◽

Host Community ◽

Rapid Expansion ◽

List Type ◽

Microbiota Composition ◽

Sheep Population ◽

Gut Microbiota Composition

AbstractNext-generation sequencing (NGS) is a recent and powerful tool for quantifying complex within-host community dynamics in real time. Metabarcoding approaches quantifying the abundance particularly of members of microbial communities, accompanied by non-invasive faecal sampling, have facilitated a rapid expansion of wild studies of gut microbiota composition.Generalised linear mixed-effects models (GLMMs) are powerful tools commonly applied to ecological and evolutionary data to dissect variance at multiple scales spanning the environment (e.g. season and geography) and host (e.g. age and genetics) levels. Despite being widely used in ecology, these approaches are as yet not well-integrated with tools and methods used to understand variance in metabarcoding data and microbiota data.Here we outline a GLMM approach to quantifying how factors across multiple scales contribute to variation in gut microbiota composition.We apply this framework to two years of data collected from the Soay Sheep population of St. Kilda to validate the approach. Specifically, we investigate the contribution of season and host age to gut microbiota community composition in these datasets. Our approach agreed with traditional approaches in showing a strong effect of age but a weak effect of season, while also a) providing the flexibility to identify fine-scale drivers of these effects and b) estimating specific taxa shifts associated with factors of interest.These results highlight the conceptual benefits of this approach and provide the foundation for extension to more complex model formulations. We suggest that the approach presented here provides a powerful means to answer emerging questions surrounding the ecological and evolutionary roles of within-host communities using metataxonomic data.

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Annual and seasonal dynamics of ectomycorrhizal fungi colonizing white pine (Pinus strobus) seedlings following catastrophic windthrow in northern Georgia, USA

Canadian Journal of Forest Research ◽

10.1139/cjfr-2012-0410 ◽

2013 ◽

Vol 43 (3) ◽

pp. 215-223 ◽

Cited By ~ 7

Author(s):

Charles C. Cowden ◽

Chris J. Peterson

Keyword(s):

Species Composition ◽

Community Dynamics ◽

Pinus Strobus ◽

Molecular Techniques ◽

Host Community ◽

Wind Disturbance ◽

White Pine ◽

Seasonal Differences ◽

Growing Seasons ◽

Undisturbed Forest

The effect of wind disturbance on ectomycorrhizal fungal (EMF) communities in forests remains largely uninvestigated. We monitored EMF colonizing Pinus strobus L. seedlings in an oak–pine forest in northern Georgia, USA, after catastrophic wind disturbance. Over three years, we sampled naturally regenerating P. strobus seedlings across three growing seasons in the windthrow area and an adjacent undisturbed forest, identifying 53 unique EMF taxa using molecular techniques. The diversity of EMF colonizing seedlings in the undisturbed forest was consistently greater than in the windthrow area. Although the EMF compositional similarity between EMF in the gap and in the undisturbed forest was low throughout the study, many EMF taxa colonized seedlings in both the gap and the undisturbed forest. Seasonal differences in EMF composition and diversity were pronounced in the undisturbed forest, with diversity increasing from spring to fall. In contrast, EMF composition and diversity were relatively constant throughout seasons in the windthrow gap. We hypothesize that the extent of host community mortality and the extent of EMF host community regeneration following disturbance drive both EMF species composition and community dynamics. However, this hypothesis warrants further study.

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