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arXiv · 1106.3925

Quasi-Neutral theory of epidemic outbreaks

Oscar A. Pinto·Miguel A. Muñoz
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Abstract

Some epidemics have been empirically observed to exhibit outbreaks of all possible sizes, i.e., to be scalefree or scale-invariant. Different explanations for this finding have been put forward; among them there is a model for "accidental pathogens" which leads to power-law distributed outbreaks without apparent need of parameter fine tuning. This model has been claimed to be related to self-organized criticality, and its critical properties have been conjectured to be related to directed percolation. Instead, we show that this is a (quasi) neutral model, analogous to those used in Population Genetics and Ecology, with the same critical behavior as the voter-model, i.e. the theory of accidental pathogens is a (quasi)-neutral theory. This analogy allows us to explain all the system phenomenology, including generic scale invariance and the associated scaling exponents, in a parsimonious and simple way.

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Oscar A. Pinto, Miguel A. Muñoz. 2011-09-04. Quasi-Neutral theory of epidemic outbreaks. https://doi.org/10.1371/journal.pone.0021946

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