Optimal Allocation of Treatment & Retention Resources for the Vancouver HIV Continuum of Care

Vancouver’s continuum of HIV care involves testing, clinical assessment, engagement in care, highly active antiretroviral therapy (HAART), treatment support and retention in care. Effective delivery of these services can significantly impact the HIV epidemic, because patients adherent on HAART are essentially non-infectious. This work presents epidemiological modelling and optimization to assess the influence of a pilot project improving HAART access (STOP HIV/AIDS), and to optimize resource allocation among HIV treatment and retention programs for minimizing morbidity, mortality, and new HIV infections. Optimal solutions are obtained for men who have sex with men, injection drug users and female sex workers. The models are systems of ordinary differential equations. Parameters are estimated using data from the British Columbia Centre for Excellence in HIV/AIDS, Vancouver Coastal Health, published sources and expert opinion. The methods developed here are applicable to the optimization of health systems in various contexts and jurisdictions.