CRISPR-based herd immunity can limit phage epidemics in bacterial populations
- University of Liverpool, United Kingdom
- Technion - Israel Institute of Technology, Israel
- Institute of Science and Technology Austria, Austria
Abstract
Herd immunity, a process in which resistant individuals limit the spread of a pathogen among susceptible hosts has been extensively studied in eukaryotes. Even though bacteria have evolved multiple immune systems against their phage pathogens, herd immunity in bacteria remains unexplored. Here we experimentally demonstrate that herd immunity arises during phage epidemics in structured and unstructured Escherichia coli populations consisting of differing frequencies of susceptible and resistant cells harboring CRISPR immunity. In addition, we develop a mathematical model that quantifies how herd immunity is affected by spatial population structure, bacterial growth rate, and phage replication rate. Using our model we infer a general epidemiological rule describing the relative speed of an epidemic in partially resistant spatially structured populations. Our experimental and theoretical findings indicate that herd immunity may be important in bacterial communities, allowing for stable coexistence of bacteria and their phages and the maintenance of polymorphism in bacterial immunity.
Data availability
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Data from: CRISPR-based herd immunity limits phage epidemics in bacterial populationsAvailable at Dryad Digital Repository under a CC0 Public Domain Dedication.
Article and author information
Author details
Jonathan P Bollback
Funding
H2020 European Research Council (EVOLHGT No. 648440)
- Jonathan P Bollback
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Payne et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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CRISPR-based herd immunity can limit phage epidemics in bacterial populations
eLife 7:e32035.
https://doi.org/10.7554/eLife.32035
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