IL6 and hemorrhagic fever with renal syndrome: High serum concentrations of tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), IL-8, interferon-gamma (IFN-γ), and C-X-C motif chemokine ligand 10 (CXCL10) are found during the febrile, hypotensive, and oliguric phases in severe HFRS cases [28].