Stochastic dynamics of Francisella tularensis infection and replication
Fig 2
A birth-and-death process with catastrophe representing division, death and rupture.
The state n represents a macrophage with n cytosolic bacteria. There are three types of events: transition to state n + 1 (division of a bacterium, rate βn), transition to state n-1 (death of a bacterium, rate μn), and transition to state H (rupture of the macrophage with release of n bacteria, rate δn). In this work we assume that βn = βn, μn = μn and δn = δn. The states 0 and H are absorbing. The infected macrophage survives for as long as it does not reach the state H.