Methods: For this purpose, levels of 13 cytokines, namely GM-CSF, IFNγ, IL-1α, IL-1β, IL-1ra, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IL-18, and TNF-α, were measured in porcine saliva from 29 male weaning piglets (6 to 9 weeks old) with meningitis and S. suis infection (S. suis group, n = 15) and healthy controls (healthy group, n = 14). This evidence concerns the gene IL18 and infectious meningitis.