The ratio of IFN-γ/IL-10 response in the CHR and HI groups is related to the immunoregulatory effect as a mixed Th1/Th2 profile since these individuals have no impairment of lymphocytes and IFN-γ, which is a key cytokine for the control of infection (Neyer et al., 1997; Kumar et al., 1998). This evidence concerns the gene IL10 and infection.