Drug resistant and wild-type strains interaction: Investigating effects of conversion delays for possible control strategies

Abstract

Drug resistance arises when a drug such as an antimicrobial or an antineoplastic loses its effectiveness in curing a disease or health condition. The increasing threat of drug resistance is compromising medical care worldwide. To provide deeper understanding of possible measures to avoid the endemicity of drug resistant strains, many models have been proposed and analyzed on the dynamics of co-circulating wild-type and drug resistant viruses. We aim to add to these works by considering a model which incorporates the effects of delay in the evolution of resistant strain, as well as the role of the immune response and the target cells availability on the suppression of the peak load of resistant virus. The model is analyzed to discover possible impacts of delays on the system's dynamic behaviour, persistence of the two strains, and the global stability. Oscillatory behaviour and the role of delays as possible control parameters are also investigated.