Extreme Competence: Keystone Hosts of Infections

Authors: Lynn B. Martin, BriAnne Addison, Andrew G.D. Bean, Katherine L. Buchanan, Ondi L. Crino, Justin R. Eastwood, Andrew S. Flies, Rodrigo Hamede, Geoffrey E. Hill, Marcel Klaassen, Rebecca E. Koch, Johanne M. Martens, Constanza Napolitano, Edward J. Narayan, Lee Peacock, Alison J. Peel, Anne Peters, Nynke Raven, Alice Risely, Michael J. Roast, Lee A. Rollins, Manuel Ruiz-Aravena, Dan Selechnik, Helena S. Stokes, Beata Ujvari, Laura F. Grogan

Source: Trends in Ecology & Evolution, VOLUME 34, ISSUE 4, P303-314, APRIL 01, 2019

Brief summary of the paper: A few members of host populations, so-called superspreaders, have disproportionate impacts on the risk of infectious disease emergence and spread.
Several other forms of EC exist; some of which might be exceptionally protective.
To discover and understand forms of EC, it is imperative to describe the distribution of, and covariation among, traits of individual hosts that mediate the many stages of host–parasite interactions.

Here, we provide a framework to do so, emphasizing how interplay among host traits related to parasite exposure behavior, susceptibility, replicability of parasites on/in hosts, and transmissibility, comprise host competence.

We hope this framework helps reveal new forms of EC and informs and improves management of disease risk.

Individual hosts differ extensively in their competence for parasites, but traditional research has discounted this variation, partly because modeling such heterogeneity is difficult. This discounting has diminished as tools have improved and recognition has grown that some hosts, the extremely competent, can have exceptional impacts on disease dynamics. Most prominent among these hosts are the superspreaders, but other forms of extreme competence (EC) exist and others await discovery; each with potentially strong but distinct implications for disease emergence and spread. Here, we propose a framework for the study and discovery of EC, suitable for different host–parasite systems, which we hope enhances our understanding of how parasites circulate and evolve in host communities.

International Research Collaboration – What does it mean to us?

What do you reckon will be the outcome if you mix one book about the ecology and evolution of cancer, lots of  shared papers, one Dr Beata Ujvary, one Professor Fredric Thomas and a bit of funding from both the Australian Research Council and the French National Research Council ?

Well, the answer is simple – a very successful and productive international research collaboration that hopefully will allow us to better understand the mechanism of cancer.  This collaboration success was recognized earlier this year as Beata Ujvary and the team received the 2018 Vice Chancellor’s Award for International Research Collaboration.

Below: Beata and Fredric shed some light on their collaboration

How is the evolution of tumour resistance at organ-scale impacted by the importance of the organ for fitness?

Authors: Cindy Gidoin, Beata Ujvari, Frédéric Thomas and Benjamin Roche

Source: BMC Evolutionary Biology, 2018, 18:185

Brief summary of the paper:

Background

A strong variability in cancer incidence is observed between human organs. Recently, it has been suggested that the relative contribution of organs to organism fitness (reproduction or survival) could explain at least a part of the observed variation.

The objective of this study is to investigate theoretically the main factors driving the evolution of tumour resistance mechanisms of organs when their relative contribution to organism fitness is considered. We use a population-scale model where individuals can develop a tumour in a key organ (i.e. in which even a small tumour can negatively impact organism fitness), an auxiliary organ (i.e. in which only a large tumour has a relatively significant impact) or both organs because of metastasis.

Results

Our simulations show that natural selection acts in two different ways to prevent cancer in a key and an auxiliary organs. In the key organ, the strategy mostly selected is the highest resistance and only a high cost of resistance mitigates this behavior.

Inversely, we observe that a low resistance strategy can be selected in the auxiliary organ when the development of the tumour is slow and the effect of a large tumour on the mortality of the organism is relatively weak. Nevertheless, if the tumour can spread to a key organ, higher resistance strategies are selected in the auxiliary organ.

Conclusion

Finally, our study demonstrates that the relative contribution of organs to the organism fitness and the metastatic propensity of the tumour influence the evolution of tumour resistance at organ scale and should be considered by studies aiming to explain the variability in cancer incidence at organ-scale.

Urban environment and cancer in wildlife available evidence and future research avenues

Authors: Tuul Sepp , Beata Ujvari , Paul W. Ewald , Frédéric Thomas and Mathieu Giraudeau

SourceThe Royal Society, Volume 286, Issue 1894 (Published: 02 January 2019)

Brief summary of the paper: While it is generally known that the risk of several cancers in humans is higher in urban areas compared with rural areas, cancer is often deemed a problem of human societies with modern lifestyles.

At the same time, more and more wild animals are affected by urbanization processes and are faced with the need to adapt or acclimate to urban conditions. These include, among other things, increased exposure to an assortment of pollutants (e.g. chemicals, light and noise), novel types of food and new infections.

According to the abundant literature available for humans, all of these factors are associated with an increased probability of developing cancerous neoplasias; however, the link between the urban environment and cancer in wildlife has not been discussed in the scientific literature.

Here, we describe the available evidence linking environmental changes resulting from urbanization to cancer-related physiological changes in wild animals. We identify the knowledge gaps in this field and suggest future research avenues, with the ultimate aim of understanding how our modern lifestyle affects cancer prevalence in urbanizing wild populations.

In addition, we consider the possibilities of using urban wild animal populations as models to study the association between environmental factors and cancer epidemics in humans, as well as to understand the evolution of cancer and defence mechanisms against it.

Beata Ujvari to receive the Vice-Chancellor’s Award for Outstanding Contributions to Ideas 2018

The Deakin University Vice-Chancellor’s Awards for Outstanding Contributions to Ideas recognise and celebrate outstanding contributions to research made by staff encapsulating and implementing the IDEAS pillar of Deakin’s strategic agenda, LIVE the future, to ‘make a difference through world-class innovation and research.’

2018 V-C Awards @ Deakin Uni

The Vice-Chancellor’s Award for International Research Collaboration recognises the Laboratory without Borders international team which applies evolutionary principleas and ecological approaches to cancer.

Cancer is not only a major cause of mortality worldwide that touches nearly every family, but also a disease which affects all other multicellular organisms. Despite this, oncology and other biological sciences such as ecology and evolution have until very recently developed in relative isolation.

The team’s approach breaks novel ground – both experimentally and theoretically – in the understanding of cancer progression and its work will reshape the conceptual landscape of cancer biology, evolutionary ecology and biology.

Deakin University joins the Nicolas Baudin Internships in France Initiative

Christophe Penot, Ambassador of France to Australia, was welcomed on 20 November at Deakin University (Melbourne)  for a meeting devoted to the development of the university’s relations with France.

Picture by Simon Fox, Deakin University

The meeting highlighted some of the collaborations established between Deakin and France, which will be able to benefit from this program. In particular, research work brought up regarding the prevention and treatment of cancer, carried out in collaboration with the CNRS in the framework of the associated international CANECEV laboratory which was set up during the visit of the President of the Republic to Australia in May 2018.

Read more @ the Embassy of France in Canberra website.

World “One Health” Day 2018 @ Geelong Centre for Emerging Infectious Diseases

Join us on Nov 15 for GCEID’s World” One Health” Day. Hear @Deakin University researchers Dr Beata Ujvari talk about transmissible cancer in wildlife and Dr Daniel Dlugolenski talk about bird flu.

This event will showcase how researchers in Geelong are undertaking collaborative research to protect people, animals and the environment from infectious diseases.

This is an open house event, please feel free to drop in at any point throughout the day (this is a free event).

When: Thursday 15 November 2018 between 10am and 3pm.

Where: St Mary’s Building, 190 Myers Street, Geelong, 3220.

For more details and registration please visit GCEID’s website.