Perinatal transmission of human immunodeficiency virus-1 infection and maternal immunization strategies for prevention.

Abstract

To review the current understanding of the epidemiologic and pathogenetic features of human immunodeficiency virus-1 (HIV-1) infection in pregnancy and perinatal HIV infection, and to explore immunization strategies for preventing maternal-infant transmission of HIV. MEDLINE data base and reference lists of articles were used to identify relevant papers. Reports from conferences were noted if the data had not yet been published. We reviewed all English-language papers pertaining to maternal or fetal infection with HIV, immunology of HIV infection, immunization of pregnant women, or immunization against HIV. Human immunodeficiency virus infection of women is increasing, and vertical transmission of HIV to children is a growing problem. There is evidence for intrauterine, intrapartum, and immediate postpartum transmission, but it is thought that the majority of transmissions occur peripartum by a minor subset of the maternal HIV-1 strains. Diagnostic advances include measurement of HIV-specific immunoglobulin A (IgA) and improved systems for polymerase chain reaction and virus isolation from potentially infected infants. Clinical and immunologic correlates of transmission remain uncertain. The epidemiology of transmission must be determined in more diverse populations. The timing and pathogenesis of HIV transmission from infected mother to fetus require better description, and improved diagnostic tools are needed. Immunologic and mechanical determinants that prevent transmission in the majority of cases need to be identified more precisely. Clinical trials to evaluate active immunization of HIV-infected pregnant women with candidate AIDS vaccines will potentially help answer many of these questions.