Open AccessIndividual risk-aversion responses tune epidemics to critical transmissibility ( R = 1)
Author(s) -
Susanna C. Manrubia,
Zanette Dh
Publication year - 2022
Publication title -
royal society open science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.84
H-Index - 51
ISSN - 2054-5703
DOI - 10.1098/rsos.211667
Subject(s) - transmissibility (structural dynamics) , mechanism (biology) , population , econometrics , risk aversion (psychology) , economics , demography , expected utility hypothesis , mathematical economics , physics , sociology , vibration isolation , quantum mechanics , vibration
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 valueR = 1. In successive waves, individuals with gradually lower risk propensity are infected. The overall mechanism shapes well-defined 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 aroundR = 1 observed worldwide after the first few waves of COVID-19.