[NOVA Math] Seminar of Analysis

The Center of Mathematics and Applications (NOVA Math), promote the Seminar of Analysis with the title: “Group centrality in optimal and suboptimal vaccination for epidemic models in contact networks”. Fabio Chalub (NOVA Math, NOVA FCT) is the speaker.

Abstract:  The pursuit of strategies that minimize the number of individuals needing vaccination to control an outbreak is a well-established area of study in mathematical epidemiology. However, when vaccines are in short supply, public policy tends to prioritize immunizing vulnerable individuals over epidemic control. As a result, optimal vaccination strategies may not always be practical for informing real-world public policies. In this work, we focus on a disease that results in long-term immunity and spreads through a heterogeneous population, represented by a contact network. We study four well-known group centrality measures and show that the GED-Walk offers a reliable means of estimating the impact of vaccinating specific groups of individuals, even in suboptimal cases. Additionally, we depart from the search for target individuals to be vaccinated and provide proxies for identifying optimal groups for vaccination. While the GED-Walk is the most useful centrality measure for suboptimal cases, the betweenness (a related, but different centrality measure) stands out when looking for optimal groups. This indicates that optimal vaccination is not concerned with breaking the largest number of transmission routes, but interrupting geodesic ones.

This is a joint work with Jorge O. Cerdeira and Matheus Hansen (NOVA Math, Universidade NOVA de Lisboa, Portugal).

 April 23, 2025, 14:15 – 15:15, Room 112, Building IV.