Assessing epidemic risk, both the probability that pathogen introductions lead to major outbreaks and the trajectory of ongoing circulation, often relies on population-level indicators derived from compartmental models. These frameworks typically assume homogeneous mixing within epidemiological compartments, yet real populations are structured by space, behavior, and heterogeneous exposure....
We consider a stochastic epidemic model with sideward contact tracing. Infection is assumed to occur through mixing events, that is, gatherings of two or more individuals \cite{ball2022epidemic}. When an infective is diagnosed, each person infected at the same event is traced with a given probability. Instead of tracing who infected a diagnosed person or whom they later infected, sideward...
Host heterogeneity is a key driver of epidemic dynamics, yet most epidemic models assume homogeneous hosts and represent transmission and recovery using constant rates. In many infections, however, variation in within-host pathogen dynamics generates substantial differences in infectiousness, disease progression, and infection outcomes across individuals. Understanding when such heterogeneity...
We analyse an infection-age structured epidemic model where both infectivity and immunity loss depend on time since infection \cite{Scarabel2026}. The model can be formulated as a nonlinear renewal equation for the incidence or as a PDE for the infected population. Using ODE approximations and numerical bifurcation analysis, we study gamma-distributed infection durations and show that...
In recent years, there has been renewed interest in the modeling, analysis and control of epidemics. The classic SIR model presents limitations due to its assumption of fully mixed and homogeneous population. It is essential to consider network effects to account for heterogeneity in susceptibility, infectivity and interactions. In addition, different behavioral changes of the individuals may...
We present a model for a mosquito-borne epidemic outbreak in which human hosts may adopt protective behaviour against mosquito bites according to the information they receive about disease prevalence. In line with the information index approach \cite{donofrio_information-related_2009}, we assume that individuals react to this information according to a memory kernel that is continuously...
Population heterogeneity strongly shapes epidemic dynamics, beyond age, space, or contact patterns.
We focus on host susceptibility differences within the SEIR framework, using the renewal equation approach of Diekmann and Inaba. Analytical results of SEIR models with heterogeneous susceptibility show that greater susceptibility variation reduces final epidemic size.
Understanding infectious disease dynamics increasingly requires models that can capture forms of heterogeneity which are invisible to standard population-level compartmental frameworks. Real-world data reveal substantial variation across individuals and groups (e.g., in terms of spatial distribution, age structure, viral-load trajectories, contact patterns, risk exposure, and behavioural...
