Optimal Treatment Strategies in the Context of ‘Treatment for Prevention’ against HIV-1 in Resource-Poor Settings
Fig 4
Disease progression for the diagnostic-guided strategy (individual trajectory, panel A) and pro-active strategy (probabilistic measure, panel B).
The white region denotes application of treatment a1 and the gray region denotes the application of treatment a2. We assumed that the initial HIV virologic status is represented by a treatment-naive patient with high copy number of wild type virus [nC(WT) = h,nC(R1) = 0,nC(R2) = 0,nC(HR) = 0]. In panel A, the blue line represents a stochastic realization of HIV dynamics in a single individual treated with the diagnostic-guided strategy and black dots indicate diagnostic assessments. In the y-axis, all states belonging to the set of viral states ℋ, ℳ and are indicated.
denotes an undetectable total viral load, i.e. this is the set of states for which condition nC(M) ≤ ℓ for all possible virus mutants M holds (). Likewise, ℋ denotes a high total viral load, i.e. refers to all states for which for at least one viral strain M, nC(M) > m. The remaining viral states belong to ℳ. Only the initial part of the trajectory is presented (day 0–800 after treatment initiation) and details of transitions to each state are labeled for clarity. In panel B, the black, red, magenta and blue lines represent the probabilities of states ✠ (patient death), ℋ, ℳ and
after application of the pro-active strategy. Note, that for the pro-active strategy, the x-axis is logarithmically scaled.