Coexistence and non-coexistence of Markovian viruses and their hosts
  The possibility of coexistence of two competing populations is a classical question which dates back to the earliest `predator-prey' models. In this paper we study this question in the context of a model for the spread of a virus infection in a population of healthy cells. The infected cells may be seen as a population of `predators' and the healthy cells as a population of `prey'. We show that, depending on the parameters defining the model, there may or may not be coexistence of the two populations, and we give precise criteria for this. 
Jakob E. Bj\"ornberg, Erik I. Broman
math.PR