In this study, the serum levels of IL‐4 and TNF‐α were not detectable in patients, whereas IL‐12 and IFN‐γ were higher in patients with brucellosis compared to healthy subjects, suggesting the induction of Th1 cytokines in human brucellosis.(16) In addition, Galanakis et al(17) compared the level of IL‐4 in children with brucellosis and healthy controls in Greece; the results indicated the increased level of IL‐4 in both acute and chronic phases of the disease. This evidence concerns the gene TNF and brucellosis.