Dr Lucy Weinert

Title: Stick or shift: determinants of bacterial host jumps

Abstract:

The emergence of bacterial pathogenicity frequently involves interspecies transmission, categorised as "stick" (evolution in the original host, new host irrelevant for evolution) or "shift" (establishment and evolution in the new host). The distinction between these modes is critical for designing effective interventions: "shift" events necessitate targeting the pathogen in its new host, while "stick" events require focusing on the reservoir host or preventing spillover. Although these dynamics are relatively well-understood in humans, the behaviour of zoonotic bacterial pathogens in their animal reservoirs – specifically whether they exhibit "stick" or "shift" dynamics – remains a significant gap in our knowledge. This talk will investigate these dynamics in two key zoonotic systems, Staphylococcus aureus and Streptococcus suis, emphasising the crucial role of mobile genetic elements in shift events. We argue that a deeper understanding of element dynamics is essential for predicting host shifts and developing effective strategies to prevent novel human bacterial pathogen emergence.

Bio:

Lucy trained as an evolutionary biologist completing her PhD on arthropod endosymbiosis at Edinburgh University in 2009. She then worked as a postdoctoral researcher specialising on phylodynamic analyses of genome sequencing data from HIV, Varicella zoster virus, Yersinia pestis and Staphylococcus aureus in Edinburgh, London, Cambridge and Montpellier, France. She subsequently won two fellowships from the Royal Society and Wellcome Trust to start her research group at the Department of Veterinary Medicine, University of Cambridge in 2015. She is currently an Associate Professor leading a group researching the emergence of pathogenicity and antimicrobial resistance in zoonotic bacteria.

 

First published: 19 August 2025

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