Abstract
HIV/AIDS has become one of the major global health burdens and threat to public health. By the end of 2021, 38.4 million people globally were living with HIV and over 1.4 million people live with HIV in Kenya. The ''HIV care cascade'' serves as an individual-level tool for evaluating HIV care and treatment results and a population-level paradigm for estimating the percentage of HIV-positive individuals in a given region who are participating in each subsequent phase. Several factors have been highlighted to influence the HIV care cascade and among this is depression which influences the improvements in ART service provision; diagnosis of people living with HIV and AIDS (PLWHA), linkages to care, continued engagement in HIV care and retention in HIV care which are crucial in attaining the 95% on ART target in the sub-Saharan region. Thus, This study employed mathematical compartmental modeling to investigate the impact of depression treatment on the HIV care cascade dynamics in Kenya. A deterministic compartmental model of the depression and HIV care cascade was developed from a system of Ordinary Differential Equations (ODEs). The basic reproduction number was evaluated using the next generation matrix. The numerical results showed that improving depression treatment can positively influence the HIV care cascade, leading to improved outcomes, such as higher rates of testing, linkage, adherence, retention, and viral suppression. The study highlights the importance of integrating depression treatment into HIV care services and provides valuable insights for policymakers and healthcare providers on how to improve the HIV care cascade dynamics in Kenya.