A method of assessing an intracellular pathogen infection and/or monitoring an intracellular pathogen infection in an individual comprises determining whether the individual has (a) T-cells that secrete IFN-γ only, (b) T-cells that secrete IL-2 only or (c) T-cells that secrete both IFN-γ and IL-2 in response to an intracellular pathogen antigen and optionally determining any change in this cytokine profile.
