The probability of epidemic burnout in the stochastic SIR model with vital dynamics

We present an approach to computing the probability of epidemic "burnout," i.e., the probability that a newly emergent pathogen will go extinct after a major epidemic. Our analysis is based on the standard stochastic formulation of the Susceptible-Infectious-Removed (SIR) epidemic model including host demography (births and deaths) and corresponds to the standard SIR ordinary differential equations (ODEs) in the infinite population limit. Exploiting a boundary layer approximation to the ODEs and a birth-death process approximation to the stochastic dynamics within the boundary layer, we derive convenient, fully analytical approximations for the burnout probability. We demonstrate-by comparing with computationally demanding individual-based stochastic simulations and with semi-analytical approximations derived previously-that our fully analytical approximations are highly accurate for biologically plausible parameters. We show that the probability of burnout always decreases with increased mean infectious period. However, for typical biological parameters, there is a relevant local minimum in the probability of persistence as a function of the basic reproduction number [Formula: see text]. For the shortest infectious periods, persistence is least likely if [Formula: see text]; for longer infectious periods, the minimum point decreases to [Formula: see text]. For typical acute immunizing infections in human populations of realistic size, our analysis of the SIR model shows that burnout is almost certain in a well-mixed population, implying that susceptible recruitment through births is insufficient on its own to explain disease persistence.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:121

Enthalten in:

Proceedings of the National Academy of Sciences of the United States of America - 121(2024), 5 vom: 30. Jan., Seite e2313708120

Sprache:

Englisch

Beteiligte Personen:

Parsons, Todd L [VerfasserIn]
Bolker, Benjamin M [VerfasserIn]
Dushoff, Jonathan [VerfasserIn]
Earn, David J D [VerfasserIn]

Links:

Volltext

Themen:

Epidemics
Extinction
Journal Article
SIR model
Stochastic processes

Anmerkungen:

Date Completed 29.01.2024

Date Revised 04.02.2024

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1073/pnas.2313708120

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM367678489