An environmentally-driven two-strain mutualistic coinfection model with
coupling transmission in vivo and vitro and humoral immunity
Abstract
In this paper, a coupling transmission epidemic model with mutualistic
two-strain of virus in body and vitro of host is proposed, in which
humoral immune response only works for strain 1 due to immunity evasion
of mutation. For the within-host subsystem, the global stability of all
feasible equilibria with and without environmental influence are
discussed. For the between-host subsystem, the basic reproduction number
R 0 is obtained. When R 0 < 1 , the disease-free equilibrium
is local stable, while the endemic equilibrium is local stable and the
disease is uniformly persistent if R 0 > 1 . Meanwhile,
backward bifurcation would occur when there exists immune response
within host. Finally, numerical examples are provided to illustrate
obtained conclusions, by which we find that the mutualism between two
strains during co-infection leads to a more persistent disease than
single strain, even the basic reproduction number is small than 1 in
each single strain.