Mathematical Modelling of Natural Phenomena

Research Article

On the Dynamics of a Two-Strain Influenza Model with Isolation

F. Chamchoda1a2 c1 and N.F. Brittona2

a1 Department of Mathematics, University of Miami, Coral Gables, Miami, FL 33124-4250, USA

a2 Centre for Mathematical Biology, Department of Mathematical Sciences, University of Bath, Bath BA2 7AY, UK


Influenza has been responsible for human suffering and economic burden worldwide. Isolation is one of the most effective means to control the disease spread. In this work, we incorporate isolation into a two-strain model of influenza. We find that whether strains of influenza die out or coexist, or only one of them persists, it depends on the basic reproductive number of each influenza strain, cross-immunity between strains, and isolation rate. We propose criteria that may be useful for controlling influenza. Furthermore, we investigate how effective isolation is by considering the host’s mean age at infection and the invasion rate of a novel strain. Our results suggest that isolation may help to extend the host’s mean age at infection and reduce the invasion rate of a new strain. When there is a delay in isolation, we show that it may lead to more serious outbreaks as compared to no delay.

(Online publication June 06 2012)

Key Words:

  • isolation;
  • influenza;
  • strain dynamics

Mathematics Subject Classification:

  • 92B05


c1 Corresponding author. E-mail: