Epidemics with Multistrain Interactions: The Interplay Between Cross Immunity and Antibody-Dependent Enhancement

TL;DR

This paper analyzes how cross immunity and antibody-dependent enhancement influence multistrain epidemic dynamics, revealing that weak cross immunity stabilizes outbreaks while strong cross immunity can induce chaos.

Contribution

It provides an analytical and numerical study of the combined effects of cross immunity and ADE on epidemic stability and chaos in multistrain diseases.

Findings

Weak cross immunity stabilizes epidemic dynamics.

Strong cross immunity can cause oscillations and chaos.

Higher ADE levels are needed for chaos with weak cross immunity.

Abstract

This paper examines the interplay of the effect of cross immunity and antibody-dependent enhancement (ADE) in mutistrain diseases. Motivated by dengue fever, we study a model for the spreading of epidemics in a population with multistrain interactions mediated by both partial temporary cross immunity and ADE. Although ADE models have previously been observed to cause chaotic outbreaks, we show analytically that weak cross immunity has a stabilizing effect on the system. That is, the onset of disease fluctuations requires a larger value of ADE with small cross immunity than without. However, strong cross immunity is shown numerically to cause oscillations and chaotic outbreaks even for low values of ADE.