The antiretroviral treatment (ART) against HIV has the clinical goal of achieving the so-called viral suppression, namely the reduction of plasma viral load under the threshold of detectability. Following the introduction of Highly Active ART in the clinical practice, a state of viral suppression (i.e. complete response to ART) can actually be reached by the majority of patients. However, a substantial fraction of subjects under treatment still shows only a partial control of viraemia. Besides being a threat for the patient, a not completely controlled viral load could have an impact on the whole epidemic evolution. Indeed, treated subjects without viral suppression maintain some infectivity, in contrast to virally suppressed subjects whose infectivity can reasonably be thought negligible. Since treated subjects are the dominant fraction among infected in Italy, the overall infectivity of this subpopulation may be comparatively important. To investigate the implications of the partial response to ART, starting from the model proposed in [1], we developed an ODE model that better describes the population of treated individuals. To represent the intra-host disease progression, the infected naive population is subdivided in a cascade of 4 compartments according to the CD4 counts, with the last compartment representing individuals in the AIDS state. Two different compartments account for treated patients who achieve viral suppression and, respectively, for treated patients with only partial viral control. The (time-varying) exchange rates between these compartments have been calibrated using data on the prevalence of viral suppression in the period 2003--2015 stored in the Italian database ARCA (Antiviral Response Cohort Analysis). Predictions on the evolution of the epidemic have then been made under different scenarios. [1] F. Papa, F. Binda, G. Felici, M. Franzetti, A. Gandolfi, C. Sinisgalli, C. Balotta, A simple model of HIV epidemic in Italy: the role of the antiretroviral treatment, Mathematical Biosciences and Engineering, published online, Vol. 15, 181-207, 2018. doi:10.3934/mbe.2018008
Partial vs. complete response to antiretroviral treatments in a model of the HIV epidemic in Italy, presented at MOBI 2017, 2017
Federico Papa;Giovanni Felici;Alberto Gandolfi;Carmela Sinisgalli
2017
Abstract
The antiretroviral treatment (ART) against HIV has the clinical goal of achieving the so-called viral suppression, namely the reduction of plasma viral load under the threshold of detectability. Following the introduction of Highly Active ART in the clinical practice, a state of viral suppression (i.e. complete response to ART) can actually be reached by the majority of patients. However, a substantial fraction of subjects under treatment still shows only a partial control of viraemia. Besides being a threat for the patient, a not completely controlled viral load could have an impact on the whole epidemic evolution. Indeed, treated subjects without viral suppression maintain some infectivity, in contrast to virally suppressed subjects whose infectivity can reasonably be thought negligible. Since treated subjects are the dominant fraction among infected in Italy, the overall infectivity of this subpopulation may be comparatively important. To investigate the implications of the partial response to ART, starting from the model proposed in [1], we developed an ODE model that better describes the population of treated individuals. To represent the intra-host disease progression, the infected naive population is subdivided in a cascade of 4 compartments according to the CD4 counts, with the last compartment representing individuals in the AIDS state. Two different compartments account for treated patients who achieve viral suppression and, respectively, for treated patients with only partial viral control. The (time-varying) exchange rates between these compartments have been calibrated using data on the prevalence of viral suppression in the period 2003--2015 stored in the Italian database ARCA (Antiviral Response Cohort Analysis). Predictions on the evolution of the epidemic have then been made under different scenarios. [1] F. Papa, F. Binda, G. Felici, M. Franzetti, A. Gandolfi, C. Sinisgalli, C. Balotta, A simple model of HIV epidemic in Italy: the role of the antiretroviral treatment, Mathematical Biosciences and Engineering, published online, Vol. 15, 181-207, 2018. doi:10.3934/mbe.2018008I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
