IL6 and infection: For the 4 other markers with significant effects (CRP, SAA, IL-6, and TNF-α), we observed that CRP was significantly associated with chronic pathology (both CP Ag+ and CP Ag−); SAA and TNF- α were significantly associated with infection status (both CP Ag+ and INF); and IL-6 was associated with both pathology and the infection status (data not shown).