Improving The Realism Of Deterministic Multi-Strain Models: Implications For Modelling Influenza A

Understanding the interaction between epidemiological and evolutionary dynamics for antigenically-variable pathogens remains a challenge.


Here we develop a set of relatively simple deterministic models of the transmission dynamics of multi-strain pathogens which give increased biological realism compared with past work. We allow the intensity of cross-immunity generated against one strain given exposure to a different strain to depend on the extent of genetic difference between the strains.


The dynamics of this model are determined by the interplay of parameters defining the cross-immune response function and can include fully symmetric equilibria, self-organized strain structures, periodic and chaotic regimes. We then extend the model by incorporating transient strain-transcending immunity which acts as a density-dependent mechanism to lower overall infection prevalence and thus pathogen diversity.


We conclude that while some aspects of the evolution of influenza can be captured by deterministic models, overall, the description obtainable using a purely deterministic framework is unsatisfactory, implying that stochasticity of strain generation (via mutation) and extinction needs to be captured to appropriately capture influenza dynamics


Journal of the Royal Society Interface


Journal of the Royal Society Interface is the Society's cross-disciplinary publication promoting research at the interface between the physical and life sciences. It offers rapidity, visibility and high-quality peer review and is ranked fifth in JCR's multidisciplinary category. The journal also incorporates Interface Focus, a peer-reviewed, themed supplement, each issue of which concentrates on a specific cross-disciplinary subject


Journal of the Royal Society Interface