We demonstrated here significantly higher TNF-α serum levels in the SI (AVL) profile than in CG and in the AI profile as compared to III, demonstrating for the first time in Brazil that during early onset of infection with a negative DTH response (III profile) TNF-α serum levels are lower than those seen in resistant asymptomatic infections with positive DTH responses (AI profile) or in susceptible symptomatic infections with negative DTH responses (SI profile [AVL]). This evidence concerns the gene TNF and infection.