Opoku-Sarkodie, RichmondBartha, Ferenc A.Polner, MónikaRöst, Gergely2024-05-282024-05-282022-07-29Opoku-Sarkodie, R., Bartha, F. A., Polner, M., & Röst, G. (2022). Dynamics of an SIRWS model with waning of immunity and varying immune boosting period. Journal of Biological Dynamics, 16(1), 596-618.https://ir.mug.edu.gh/handle/123456789/233SIRS models capture transmission dynamics of infectious diseases for which immunity is not lifelong. Extending these models by a W compartment for individuals with waning immunity, the boosting of the immune system upon repeated exposure may be incorporated. Previous analyses assumed identical waning rates from R to W and from W to S. This implicitly assumes equal length for the period of fullimmunityandofwanedimmunity.Werelaxthisrestriction,andallowan asymmetric partitioning of the total immune period. Stability switches of the endemic equilibrium are investigated with a combination of analytic and numerical tools. Then, continuation methods are applied to track bifurcations along the equilibrium branch. We find rich dynamics: Hopf bifurcations, endemic double bubbles, and regions of biostability. Our results highlight that the length of the period in which waning immunity can be boosted is a crucial parameter significantly influencing long term epidemiological dynamics.enWaning immunityimmune boostingSIRWS systempartitioning of immunityHopf bifurcationArticle