INFANT HIV INFECTION MAY BE CONNECTED TO VITAMIN A By Christine A. Rowett Pregnant women with the HIV virus may have the ability to decrease the chances of transmitting the infection to their unborn children. School of Public Health researchers have found that HIV-infected mothers who are deficient in vitamin A during pregnancy are three to four times more likely to pass the HIV infection to their child. Vitamin A is essential to the immune system. "Our study raises the possibility that improving the mother's nutrition through vitamin supplementation during pregnancy may be a potential strategy to decrease the chance of her having an HIV-infected child," said Richard Semba, lead author of the study. Dr. Semba is an assistant professor with the Center for Human Nutrition, Department of International Health. The researchers' findings were published in the June 25 issue of The Lancet. Dr. Semba said the study of nutrition and infectious diseases should be more closely examined. "The area of nutrition and HIV infection has been somewhat neglected," he said. "It seems that we have ignored some basic things." As part of the four-year study, which was conducted in Malawi, Africa, researchers examined the vitamin A levels of 338 HIV-infected women during their pregnancies. The infants were studied from birth to age 1. The vitamin A-deficient mothers had a significantly higher transmission rate. Thirty-two percent of mothers low in vitamin A transmitted the virus to their children; only 7 percent of babies born to mothers with healthy levels of the vitamin were born with the virus. "Vitamin A deficiency may explain why some HIV-infected mothers have HIV-infected infants and others do not," Dr. Semba said. "This may be due to the important role that vitamin A plays in stimulating the immune system." Currently, about 10 to 40 percent of infants born to HIV-infected mothers are born with the virus worldwide. The figure for infants in the United States is approximately 10 to 15 percent. There are three ways an HIV-infected mother can transmit the virus, Dr. Semba said: during pregnancy, during delivery and through breast-feeding. In developing parts of the world, many HIV-infected mothers are unaware they have the virus, and the benefits of breast-feeding far outweigh the risks of bottle-feeding, he said. "Breast-feeding is how infants get most of their nutrients," Dr. Semba said, "and it would be a disaster to advocate that women stop breast-feeding." Caesarean sections to reduce infant exposure to HIV-infected blood are not a viable option in developing countries. The pregnant women in the study who had deficient vitamin A levels had about one-half the amount of vitamin A as women with sufficient levels, he said. "We found that vitamin A deficiency was common in HIV-infected women, and, the worse the deficiency, the higher the HIV transmission rate," he said. Pregnant mothers can increase their vitamin A levels by increasing their intake of liver, spinach, carrots or prenatal vitamin supplements. Dr. Semba said he has been studying vitamin A for about seven years, initially doing research with School of Public Health Dean Alfred Sommer, who determined that regular vitamin A supplementation could reduce child mortality by about one-third in developing countries. "When we confirmed that vitamin A was also making the immune system stronger, it was quite natural to turn to HIV and AIDS," Dr. Semba said. He stressed, however, that there is no concrete proof that vitamin A will affect the progress of HIV infection or AIDS. "I would caution against people taking mega-doses of vitamins because they think it might help them," he said. "Until studies are done that can establish what is beneficial, it is not a good idea to take too much of any vitamin." There is currently an "urgent search" for prevention methods to avoid HIV-infected newborns, he said. "Worldwide, the number of HIV-infected children is growing into the millions," he said. The research team will further examine their findings through upcoming clinical trials in sub-Saharan Africa as soon as next year, Dr. Semba said. He said he hopes those studies will determine whether a prenatal supplement including vitamin A would increase the chance for healthy births. The vitamin A/HIV study was supported by the National Institutes of Health and the United States Agency for International Development.
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