Topological dependence of viral mutation spread in complex host-interaction networks

The increase in the connectivity between hosts in recent times has facilitated the emergence of more aggressive mutant viral strains, making their containment and eradication significantly more challenging compared to the original variants. We focus on the evolution of a new more aggressive mutant strain that appears at specific nodes in the system and competes with a previous version until reaching fixation. The role of host-interaction network topology in the emergence and spatial diffusion of these highly contagious strains is analyzed, as well as how network-based interventions can help mitigate their spread. To address these issues, we present simplified mathematical models that qualitatively describe the occurrence, propagation, and impact of such mutations within host-interaction networks. By incorporating the heterogeneous topology of the host network into the analysis, a more advanced framework is proposed to curb the growth of mutant strains. Extensive numerical simulations of these models offer insights into the mechanisms driving viral evolution, the dynamics of contagion, and the critical topological influence of the initial seed nodes under different kinetic regimes, providing a robust perspective on viral spread and containment strategies.