ALB and infection: We included the following variables: age, gender, having a breakthrough(BT) infection, virus variant (as determined as the dominant type at the time of having a PCR positive test), race/ethnicity (White, Asian, Black, Hispanic), BMI, COVID-19 symptoms at the time of presentation (fatigue, shortness of breath, fever, and palpitations), the Elixhauser Comorbidity Index (EI) and laboratory studies including white blood cell count (WBC) count, D-Dimer, CRP, platelet count and albumin.