AEGiS-15IAC: Gender differences in perinatal HIV acquisition among African infants.

15th International AIDS Conference

Bangkok, Thailand - July 11-16, 2004

Gender differences in perinatal HIV acquisition among African infants.

Int Conf AIDS 2004 Jul 11-16; 15:(abstract no. ThOrC1420)

Taha TE, Nour S, Kumwenda NI, Broadhead RL, Fiscus SA, Kafulafula G, Nkhoma C, Chen S, Hoover DR
Johns Hopkins University, Baltimore, MD, United States

BACKGROUND: Several studies have reported on rates of mother-to-child transmission (MTCT) of HIV and risk factors associated with transmission. However, if gender of the offspring increases susceptibility to infection is not known. We investigated gender-specific rates of MTCT of HIV among babies born to HIV infected mothers.

METHODS: We prospectively followed babies enrolled in two randomized, phase III clinical trials of perinatal HIV transmission concurrently conducted between 2000 and 2003 in Blantyre, Malawi, Africa. All babies born to HIV positive women who enrolled in these clinical trials were eligible. Babies were enrolled at birth, seen at age 6-8 weeks and followed through 3 to 24 months. The HIV status of all babies was assessed at birth and in about 90% at age 6-8 weeks. MTCT of HIV among boys and girls at birth and 6-8 weeks, and HIV transmission rates among babies not HIV infected at birth were estimated.

RESULTS: Overall 966 boys and 998 girls were included in this study. At birth, significantly more girls (12.6%) were HIV infected than boys (6.3%) (p<0.0001). This association remained significant after controlling for maternal viral load and other factors (p<0.0001). Similarly, among breastfed babies uninfected at birth, more girls acquired HIV by 6-8 weeks (10.0%) compared to boys (7.4%); (p=0.07). Mortality rates at two years of age were also modestly higher among girls (28.2%) compared to boys (22.8%) (p=0.05). Conclusion Female babies may be more susceptible to HIV infection antepartum and continuing postpartum. Alternatively, in utero mortality of HIV infected males may be disproportionately higher than females and therefore more HIV infected female babies are born. Since approximately 30% of childbearing women are HIV infected in parts of Africa, the magnitude of the gender transmission differences observed in this study could have major treatment, prevention, vaccine and demographic implications.

Keywords: AEGIS, Acquired Immunodeficiency Syndrome, HIV Seropositivity, HIV Infections, Viral Load, Risk Factors, Malawi, Breast Feeding, Sex Characteristics, Mothers, Africa, Infant, Infant, Newborn, Humans, Female, Male, Child, transmission

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ThOrC1420