In a broad spectrum of viral infections, proteases remain the first line of host defences, including neutrophil serine proteases (human neutrophil elastase, cathepsin G, proteinase 3, neutrophil serine protease 4/NSP4, and granzymes) that contribute to the formation of neutrophil extracellular traps (NETs) or caspases in cytotoxic lymphocytes that orchestrate programmed cell death [22, 23]. This evidence concerns the gene PRSS57 and viral infectious disease.