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Title: Punctuated virus-driven succession generates dynamical alternations in CRISPR-mediated microbe-virus coevolution
The coevolutionary dynamics of lytic viruses and microbes with CRISPR-Cas immunity exhibit alternations between sustained host control of viral proliferation and major viral epidemics in previous computational models. Thesealternatingdynamics have yet to be observed in other host–pathogen systems. Here, we address the breakdown of control and transition to large outbreaks with a stochastic eco-evolutionary model. We establish the role of host density-dependent competition in punctuated virus-driven succession and associated diversity trends that concentrate escape pathways during control phases. Using infection and escape networks, we derive the viral emergence probability whose fluctuations of increasing size and frequency characterize the approach to large outbreaks. We explore alternation probabilities as a function of non-dimensional parameters related to the probability of viral escape and host competition. Our results demonstrate how emergent feedbacks between host competition and viral diversification render the host immune structure fragile, potentiating a dynamical transition to large epidemics.  more » « less
Award ID(s):
2022049
PAR ID:
10628780
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Royal Society
Date Published:
Journal Name:
Journal of The Royal Society Interface
Volume:
21
Issue:
217
ISSN:
1742-5689
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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