In this paper it is studied a fractional order model for the three stages of HIV epidemics with drug-resistance. The model includes CD4+ T cells, CTLs, macrophages, and the virus populations. We simulate the model for different values of the fractional derivative a 2 [0.5,1.0]. The fractional order system untangles generous dynamical characteristics, such as faster transients and slower evolutions as time increases. These traits are not seen in integer-order models, since they are customary of memory-preserving systems.
M. A. Pinto, Carla and M. Carvalho, R.
"Fractional Modeling of Typical Stages in HIV Epidemics with Drug-Resistance,"
Progress in Fractional Differentiation & Applications: Vol. 1
, Article 5.
Available at: https://dc.naturalspublishing.com/pfda/vol1/iss2/5