NEW LOOK AT HIV TRANSMISSION FROM SEROPOSITIVE MOTHERS TO THEIR INFANTS - THE FACTS BEYOND SEROLOGY

Once the curtain of maternal antibodies is removed (12-18 months) only a fraction of the infants are seropositive. Some babies from whom vir us has been isolated or detected in their cells subsequently become se ronegative. What does the negative serology of these children really t ell us about exposure to HIV? It is suggested that seroconverting is o nly one of the ways to respond to an HIV exposure from an infected mot her, it is not the only or the best way. Some form of tolerance to HIV , emerging after in utero exposure of the fetus, could theoretically l ead to a seronegative state despite infection. Based on monkey studies with simian immunodeficiency virus (SIV), this tolerance could offer protection against pathological outcome of the infection. Seronegative yet infectediexposed children of HIV-positive mothers exist, though t heir number remains unknown. They might hold the key to a protective i mmunity to HIV.