Modelling the Impact of Stages of HIV Progression on Estimates

Angelina Mageni Lutambi

Ifakara Health Institute, Dar es Salaam, Tanzania.

DOI: 10.4236/aid.2015.53012                

Abstract

HIV/AIDS is a public health problem especially in sub-Saharan Africa where majority of infections and deaths occur. Despite the large number of studies and efforts made in covering the data gap using mathematical models, little is known on how model estimates are confounded by the transmission variabilities that exist in stages of HIV progression. This work investigates the impact of including stages of HIV transmission in HIV/AIDS models. A deterministic HIV/AIDS model is developed and extended to include stages of HIV progression of infected individuals. Theoretical investigation of the models and numerical analyses indicate that the two models produce different estimates, with the model without stages producing lower estimates than the staged model. These results call for a careful consideration in evaluating the efficiency of HIV/AIDS models that are used to estimate and project the burden of HIV/AIDS disease.

Keywords

HIV Stages, Transmission, Mathematical Model, Population Dynamics, Model Estimates

Conflicts of Interest

The authors declare no conflicts of interest.

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