Individual risk-aversion responses tune epidemics to critical transmissibility (R = 1)

Changes in human behaviour are a major determinant of epidemic dynamics. Collective activity can be modified through imposed control measures, but spontaneous changes can also arise as a result of uncoordinated individual responses to the perceived risk of contagion. Here, we introduce a stochastic...

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Bibliographic Details
Authors: Manrubia, S., Zanette, Damian Horacio
Format: article
Status:Published version
Publication Date:2022
Country:Argentina
Institution:Consejo Nacional de Investigaciones Científicas y Técnicas
Repository:CONICET Digital (CONICET)
Language:English
OAI Identifier:oai:ri.conicet.gov.ar:11336/217051
Online Access:http://hdl.handle.net/11336/217051
Access Level:Open access
Keyword:EFFECTIVE REPRODUCTION NUMBER
INFECTION WAVES
POPULATION DYNAMICS
RISK-TAKING PROPENSITY
SIR EPIDEMICS
UNCOORDINATED INDIVIDUAL RESPONSES
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Description
Summary:Changes in human behaviour are a major determinant of epidemic dynamics. Collective activity can be modified through imposed control measures, but spontaneous changes can also arise as a result of uncoordinated individual responses to the perceived risk of contagion. Here, we introduce a stochastic epidemic model implementing population responses driven by individual time-varying risk aversion. The model reveals an emergent mechanism for the generation of multiple infection waves of decreasing amplitude that progressively tune the effective reproduction number to its critical value R=1. In successive waves, individuals with gradually lower risk propensity are infected. The overall mechanism shapes welldefined risk-aversion profiles over the whole population as the epidemic progresses. We conclude that uncoordinated changes in human behaviour can by themselves explain major qualitative and quantitative features of the epidemic process, like the emergence of multiple waves and the tendency to remain around R = 1 observed worldwide after the first few waves of COVID-19.