CRP and COVID-19: While lymphocyte levels consistently below 1*10^9/L may represent an abnormality in their acquired immune function [18], LDH, CRP, and D-Di offer complementary information about the systemic consequences of viral infections and the immune system's efforts to combat them. Considering this, our study aims to conduct a comprehensive analysis of the protective effect of COVID-19 vaccines in patients with varying immune statuses.