Optimal intervention strategies of staged progression HIV infections through an age-structured model with probabilities of ART drop out

TL;DR

This paper develops an age-structured HIV transmission model with intervention strategies, analyzing disease dynamics and optimizing treatment interventions considering ART dropout probabilities.

Contribution

It introduces a novel age-structured model with HIV progression stages and analyzes optimal intervention strategies including ART dropout effects.

Findings

Disease-free equilibrium is stable when R0 ≤ 1.

Endemic equilibrium persists when R0 > 1.

Optimal intervention strategies can minimize AIDS cases.

Abstract

In this paper, we construct a model to describe the transmission of HIV in a homogeneous host population. By considering the specific mechanism of HIV, we derive a model structured in three successive stages: (i) primary infection, (ii) long phase of latency without symptoms and (iii) AIDS. Each HIV stage is stratified by the duration for which individuals have been in the stage, leading to a continuous age-structure model. In the first part of the paper, we provide a global analysis of the model depending upon the basic reproduction number R 0. When R 0 $\le$ 1, then the disease-free equilibrium is globally asymptotically stable and the infection is cleared in the host population. On the contrary, if R 0 > 1, we prove the epidemic's persistence with the asymptotic stability of the endemic equilibrium. By performing the sensitivity analysis, we then determine the impact 1 of control-related parameters of the outbreak severity. For the second part, the initial model is extended with intervention methods. By taking into account ART interventions and the probability of treatment drop out, we discuss optimal interventions methods which minimize the number of AIDS cases.