Early predictive factors of HIV infection in infants born to HIV infected mothers were carried out to evaluate the roles of immunological parameters for the diagnosis and prognosis of HIV infection. T-lymphocyte subsets and serum immunoglobulins were studied on cord blood in three groups of neonates: 14 infected infants, 29 sero-reverted infants and 31 control neonates. No differences were observed between the three groups. At 3 months, IgG were significantly higher in the infected infants than in sero-reverted infants. After 6 months, CD4 + cell counts, CD4/CD8 ratio were significantly lower in the infected infants and serum IgG, IgA and IgM were significantly higher in the infected group. Antigenemia p24 was detected in 78% of the infected group before 6 months. Total HIV-specific antibody persisted and progressed after 6 months. These data and viral detection appear to be complementary and useful for therapeutic strategies.