R0 centrality based control of epidemic diseases in metropolitan commute networks

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K22447
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 45:Biology at organismal to population levels and anthropology, and related fields
• Research Institution: The Graduate University for Advanced Studies
• Principal Investigator: Sasaki Akira 総合研究大学院大学, 統合進化科学研究センター, 教授 (90211937)
• Project Period (FY): 2019-06-28 – 2023-03-31
• Keywords: 環境の異質性 / メタ個体群 / 免疫逃避 / 毒性の進化 / 生きた化石 / 種分化のホットスポット / 形質分岐 / 集団構造

Outline of Final Research Achievements

To understand the spread of infectious diseases and evolution of traits in heterogeneous meta-populations, in which local populations with heterogeneous conditions are connected by migration of individuals, we have developed R0 centrality theory and meta-population invasion fitness theory to show that (1) pathogens that repeatedly escape host immunity have a general tendency to become highly virulent, (2) that heterogeneity in migration rates and productivity in meta-populations invariably increases pathogen virulence to be evolved, (3) and that the evolutionary dynamics of a taxa that evolve under productivity gradients from the center to peripheral niche has led to the emergences of speciation hotspot in the central niche and "living fossils" in the peripheral niche.

Free Research Field

数理生物学

Academic Significance and Societal Importance of the Research Achievements

人間社会も野生生物の個体群の異質な環境のもとで複雑なネットワークで繋がっており、このような空間的異質性や結合の異質性が、伝染病の伝播や制圧、形質の進化にもたらす影響を解明することには大きな社会的要請がある。この理論研究により導入されたR0中心性やメタ個体群侵入適応度の概念は、多様で複雑な構造のもとでの流行や進化を解明する上でのブレークスルーとなりうる。この研究ですでに、「宿主個体群の異質性が病原体の毒性を必ず上昇させる」、「宿主集団の免疫力の異質性が病原体の免疫逃避速度を上昇させる」などの一般的で重要な理論的知見が得られている。