Ecology and evolution of infectious diseases

Colloquium 3. Main activity: Year 2012-2017

Background

Due to their short generation time, bacterial pathogens such as Y. pestis (bubonic plague) and B. anthracis (anthrax) are excellent model organisms to study the effects of ecology on genetic evolution. Because both pathogens can cause large-scale lethal epidemics in their wildlife host populations and can persist within an area for long periods of time (either in the soil or in vector species), they exert a strong selection pressure on host population dynamics, host innate resistance, and/or their own virulence. In addition, anthropogenic factors such as changes to land use and trade routes have affected the global distribution and genetic variation of these pathogens. Finding out exactly how the factors mentioned above have influenced the evolution of plague and anthrax will be a major challenge; the phylogeny of Y. pestis has led to much speculation on the disease’s origin and the role of ecosystem dynamics in its global persistence. Furthermore, the co-evolution between plague and wildlife rodents has resulted in a huge variation in host susceptibility and plague virulence levels (up to a 109th-fold difference in lethal dose), even within the same host rodent species. For B. anthracis, we have a good grasp of its ecology, but there are still many open questions regarding this species; for example, the origin of the plasmids that allow it its unique mode of existence. Projects in Etosha National Park in Namibia are focused on elucidating key question of the pathogen’s eco-epidemiological cycle.

Summary of focus

To explore the molecular evolution, persistence, and distribution of disease pathogens through empirical and theoretical work.

Accomplishments

  • Hosting of ESF Plague Meeting in 2012

Associated Projects

LAND: Partial migration of red deer and tick distribution at the altitudinal colonization border (TickDeer)

TickDeer

PlagueEco2Geno - Reconstructing the imprint of ecology on the genetic phylogeography of the Plague in Central Asia and China

IRFP: Rainfall and herbivory: characterizing the transmission route for anthrax in grazing wildlife (NSF Fellowship)

MedPlag - The medieval plagues: ecology, transmission modalities and routes of the infections. (ERC Advanced Grant, Starts 2013)

Current goals

We will tackle many of the challenges related to plague and anthrax by combining ecological niche modelling tools with historical epidemiological outbreak records, and modern sequencing techniques such as ancient DNA sequencing, and whole-genome sequencing. Together, these sources of information provide a unique view on the evolution of these two highly pathogenic bacteria in the context of their ecology.

Collaborators

Norway:

USA:

China:

Published Nov. 27, 2012 11:06 AM - Last modified Aug. 20, 2014 03:25 PM