Figure 1

Schematic of the novel exponential model. The variables T(t), I(t) and V(t) denote the number of target and infected cells per ml and the amount of viruses per ml, respectively, at time t. The parameter Δ denotes the loss rate of target cells per day after the flat phase, β the rate constant for viral infection of target cells, and c the clearance rate of virus particles. δ denotes the death rate and p the viral production rate of infected cells. t^* represents the time at which the target cells start declining with slope –∆.