Impact of Heterogeneous Human Activities on Epidemic Spreading

TL;DR

This study investigates how population-level heterogeneity in human activity rates influences epidemic spreading, revealing that such heterogeneity significantly accelerates the spread even when individuals behave uniformly.

Contribution

It demonstrates that population heterogeneity in activity levels impacts epidemic speed more than individual activity patterns, refining understanding of epidemic dynamics.

Findings

Heterogeneity at population level affects spreading speed.

System heterogeneity influences epidemic dynamics more than individual activity patterns.

Model shows increased sensitivity to population heterogeneity.

Abstract

Recent empirical observations suggest a heterogeneous nature of human activities. The heavy-tailed inter-event time distribution at population level is well accepted, while whether the individual acts in a heterogeneous way is still under debate. Motivated by the impact of temporal heterogeneity of human activities on epidemic spreading, this paper studies the susceptible-infected model on a fully mixed population, where each individual acts in a completely homogeneous way but different individuals have different mean activities. Extensive simulations show that the heterogeneity of activities at population level remarkably affects the speed of spreading, even though each individual behaves regularly. Further more, the spreading speed of this model is more sensitive to the change of system heterogeneity compared with the model consisted of individuals acting with heavy-tailed inter-event time distribution. This work refines our understanding of the impact of heterogeneous human activities on epidemic spreading.