We also compared the immune response in COVID-19 patients to the response following COVID-19 mRNA vaccination and identified biomarkers for immunological outcomes, including CXCL10, MCP-1, and IFN gamma, that are shared between individuals receiving BNT162b2 (Pfizer–BioNTech) vaccine and COVID-19 patients. Here, CXCL10 is linked to COVID-19.