DOI: 10.5061/dryad.42n44
title: Data from: CRISPR-based herd immunity limits phage epidemics in bacterial populations

description: 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.
description: 10%susceptibleTime-lapse images of spread of T7 phage epidemics in Escherichia coli spatially structured populations over 48 hours. Archive contains images of the following treatment: 10% susceptible, 90% resistant cells.20%susceptibleTime-lapse images of spread of T7 phage epidemics in Escherichia coli spatially structured populations over 48 hours. Archive contains images of the following treatment: 20% susceptible, 80% resistant cells.30%susceptibleTime-lapse images of spread of T7 phage epidemics in Escherichia coli spatially structured populations over 48 hours. Archive contains images of the following treatment: 30% susceptible, 70% resistant cells.40%susceptibleTime-lapse images of spread of T7 phage epidemics in Escherichia coli spatially structured populations over 48 hours. Archive contains images of the following treatment: 40% susceptible, 60% resistant cells.50%susceptibleTime-lapse images of spread of T7 phage epidemics in Escherichia coli spatially structured populations over 48 hours. Archive contains images of the following treatment: 50% susceptible, 50% resistant cells.60%susceptibleTime-lapse images of spread of T7 phage epidemics in Escherichia coli spatially structured populations over 48 hours. Archive contains images of the following treatment: 60% susceptible, 40% resistant cells.70%susceptibleTime-lapse images of spread of T7 phage epidemics in Escherichia coli spatially structured populations over 48 hours. Archive contains images of the following treatment: 70% susceptible, 30% resistant cells.80%susceptibleTime-lapse images of spread of T7 phage epidemics in Escherichia coli spatially structured populations over 48 hours. Archive contains images of the following treatment: 80% susceptible, 20% resistant cells.90%susceptibleTime-lapse images of spread of T7 phage epidemics in Escherichia coli spatially structured populations over 48 hours. Archive contains images of the following treatment: 90% susceptible, 10% resistant cells.100%susceptible_control_run1Time-lapse images of spread of T7 phage epidemics in Escherichia coli spatially structured populations over 48 hours. Archive contains images of the following treatment: all 100% susceptible controls of run 1.100%susceptible_control_run2Time-lapse images of spread of T7 phage epidemics in Escherichia coli spatially structured populations over 48 hours. Archive contains images of the following treatment: all 100% susceptible controls of run 2.100%susceptible_control_run3Time-lapse images of spread of T7 phage epidemics in Escherichia coli spatially structured populations over 48 hours. Archive contains images of the following treatment: all 100% susceptible controls of run 3.