Nutrition and immune function II: Maternal factors influencing transmission

The risk of mother-to-child transmission of HIV ranges from 15-35 percent depending on the population under study (Fowler and Rogers 1996, Peckham and Gibb 1995). The recent finding that zidovudine treatment during pregnancy can reduce the risk of mother-to-child transmission of HIV by as much as two-thirds in some populations (CDC 1994, Connor et al. 1994), raises the question of which maternal, fetal, viral, immunologic, and placental factors play the greatest role in vertical transmission. It is clear that not only does the transmission rate vary dramatically by geographical distribution, but both the prevalence of infection and susceptibility of the uninfected may be higher in parts of the developing world. The transmission rate is significantly higher in the developing world presumably due to numerous factors including coinfection with other STD's, very little economic support for prevention, education, health maintenance or improving nutritional contributions to curb the spread of HIV. Furthermore, the strategies to reduce vertical transmission in industrialized countries are often not feasible in the developing world. Providing widescale availability of antivirals may not be feasible in areas where, to date, vitamin deficiencies often still exist. The healthcare budget in many of these developing countries cannot even pay for basic medical or prenatal services. The future directions in reducing the rate of mother-to-infant transmission must focus on strategies applicable to the developing world as well as industrialized countries. The vast majority of HIV in the pediatric age group is the result of vertical transmission of the virus. A number of maternal immunologic factors have been associated with vertical transmission. This paper offers a brief review of the extant knowledge with regard to the role of maternal factors invertical transmission of HIV infection.