MUC1 and COVID-19: While swab tests remain the primary diagnostic method for COVID-19, several biomarkers, including Krebs von den Lungen-6 (KL-6), C-reactive protein (CRP), interleukin-6 (IL-6), and SARS-CoV-2 Nucleocapsid protein (Nag), show potential for early detection, even in asymptomatic or minimally symptomatic individuals [4,5,6].