Perinatal human immunodeficiency virus infection: ruminations on mechanisms of transmission and methods of intervention.

Perinatal human immunodeficiency virus (HIV) infection is undoubtedly a multifactorial process. Neither the quantity of viremia nor the level of neutralizing antibody in the infected mother is alone predictive of HIV transmission to her offspring. Additional cofactors may include the ability of maternal immunity to control the host cell range and rate of viral replication. The placenta probably constitutes an effective barrier to viral transmission unless disrupted by processes such as syphilis. Prevention of such breaks in the trophoblast barrier and efforts to stimulate maternal and newborn HIV-specific immunity may further decrease the perinatal transmission rate.