An HBV/HCV model with intracellular delay and cell proliferation is analyzed.
Pontryagin’s method is employed to derive sharp conditions ensuring stability of the infection persistent equilibrium.
An alternative geometric stability switch criterion is proposed, which is used to show that the intracellular delay can induce stability switches.
Numerical simulations reveal that the intracellular delay can induce chaos and interesting structure of bifurcation diagram exhibiting persistence bubbles.