Diagram of viral dynamics model. Uninfected cells (T) can become infected by virus (V) to generate productively infected cells (I), long-lived infected cells (M) or latently infected cells (L). Latent infected cells may divide, sustaining this pool, which leaks to the productively infected class as latent cells are activated into cells producing virus. Dashed arrows indicate removal (death) of uninfected and infected cells, which occur at different rates. Equation (1) in the text considers only the uninfected cells, productively infected cells and virus.