COVID-19 is a disease with high mortality rates with various clinical severity (mild, severe, and critical) during three different immunogenomic phase (initial, propagating and complicating) based on one of the clinicogenomic mechanism, renin angiotensin aldosterone system. Patients with pre-existing comorbidity was reported with higher susceptibility, prevalency, and worsening outcomes such as acute respiratory distress syndrome. Individual immune system factors could contribute to susception, duration, severity and reinfection of the disease, hence why probing the comorbidities associated with COVID-19 is a comprehensive approach to reveal the biological phenomenone cuasing varying disease severity levels across COVID-19 patients. The desired goal of this literature review was to describe the correlation of comorbidity with severity of COVID-19 patient based on the three immunogenomic phases.