Epidemic spreading on modular networks: the fear to declare a pandemic

L. A. BRAUNSTEIN; S. HAVLIN; L. D. VALDEZ

PHYSICAL REVIEW E

AMER PHYSICAL SOC

Lugar: New York; Año: 2020 vol. 101

1539-3755

In the last decades, the frequency of pandemics has been increased due to the growth of urbanizationand mobility among countries. Since a disease spreading in one country could becomea pandemic with a potential worldwide humanitarian and economic impact, it is important todevelop models to estimate the probability of a worldwide pandemic. In this paper, we proposea model of disease spreading in a static modular complex network (having communities) andstudy how the number of bridge nodes n that connect communities affects the disease spreading.We find that our model can be described at a global scale as an infectious transmission processbetween communities with global infectious and recovery time distributions that depend on theinternal structure of each community and n. We find that near the critical point as n increases,the disease reaches most of the communities but each community has only a small fraction ofrecovered nodes. In addition, we obtain that in the limit n → ∞, the probability of a pandemicincreases abruptly at the critical point. This scenario could make the decision on whether tolaunch a pandemic alert or not more difficult. Finally, we show that link percolation theory canbe used at a global scale to estimate the probability of a pandemic due to the weak dependenceof the global transmissiblity (between communities) on their global recovery time.