IL6 and COVID-19: Reviewing the literature, the biomarkers involved in COVID-19 disease progression include lymphocytes, white blood cells, C-reactive protein, pro-inflammatory cytokines, interleukins (IL)-6, IL-1β, procalcitonin, lactate dehydrogenase, Krebs von den Lungen-6, and ferritin.[33,44] No clear report in the literature links the granulocyte percentage of myeloid white cells to COVID-19 progression or prognosis.