By contrast, genes with functions indicative of an innate immune response, such as pro-inflammatory cytokines [e.g., IL-18 (37)], interferon-stimulated genes [e.g., GBP1 (38), GBP4 (38), GBP5 (38), PARP14 (39)], and regulators of the innate immune system [e.g., CLIC4 (40), LRRK2 (41)], were significantly decreased in expression during late season infections. Here, IL18 is linked to infection.