Infant Feeding Choices for HIV Positive Mothers
IBCLC, Harare Zimbabwe
Ted Greiner, PhD, Uppsala University, Sweden
from Breastfeeding Abstracts,
May 2000, Volume 19, Number 4, pp.
Ever since the human immunodeficiency virus (HIV) was first identified in the breast milk of three healthy virus carriers1 and postpartum transmission of the virus to the breastfed baby was reported,2 policy-makers have grappled with the need to develop appropriate and feasible guidelines to help HIV-positive mothers decide if they should breastfeed their babies. Mothers are faced with a dilemma of competing risks:
1. the risk of mother-to-child transmission of HIV through breastfeeding, or
2. the risk of infant morbidity/mortality from other causes if breastfeeding is withheld.
The latter possibility becomes particularly meaningful in two contexts: first, in resource-poor settings where infant morbidity/mortality rates are high, and second, among those babies who already are HIV-infected at birth and for whom breastfeeding is likely to prolong life.
Mother-to-child transmission of HIV can occur during pregnancy, during birth, and during breastfeeding, but attempts to quantify the exact risk that breastfeeding plays in transmitting the virus to the individual baby have proved problematic. Among mothers who have not received any treatment with suppressive drugs, vertical mother-to-child transmission (MTCT) occurs at a higher rate during pregnancy and the birth process than during breastfeeding. Several events surrounding labor and delivery have been shown to affect the risk of transmission.3-6 Neonatal skin and mucous membranes are not effective barriers against infective organisms, and direct invasion of the skin, eyes, oral, and gastric mucosa by HIV during the birth process may play a major role in transmission.7 Prematurity and low birth weight,8 and lesions caused by fetal monitoring or vigorous oral suction of the infant at birth9 may also increase transmission of the virus to the newborn infant. Among mothers who live in countries which do not provide antiviral drugs and who themselves cannot afford to buy them, trials carried out in Thailand10 and Uganda11 showed that short course antiretroviral therapy administered to the mother late in pregnancy or at the time of delivery and/or to the infant in the postpartum period significantly reduced transmission of HIV to the infant, whether breastfed or not. Due to limitations in HIV test technology, it is not possible to determine the precise timing or mode of transmission to the newborn baby. Antibody tests such as the enzyme-linked immunosorbent assay (ELISA) are not able to detect HIV infection in babies younger than 15 to 18 months. Polymerase chain reaction (PCR), viral culture, and p24 antigen tests, although able to detect the virus itself, are not able to establish infection definitely before 2 to 3 months of age.12
The main way of roughly estimating the transmission rate through breastfeeding is thus by comparing overall vertical transmission rates between formula-fed and ever-breastfed infants. This has led to widely differing estimates, ranging from 0 to 46 percent.12 Different studies have estimated that breastfeeding accounts for transmission of the virus in 5 percent, 8 percent, 14 percent, or 18 percent of babies where maternal infection is established (i. e. , when levels of virus in the blood are expected to be low),13, 14 and 16 percent or 29 percent15 during acute maternal infection (during sero-conversion and when the mother shows symptoms of AIDS, when viremia is high).16 An international multicenter pooled analysis of mother-to-child transmission of HIV infection via breastfeeding that looked at late postnatal acquisition of HIV of infants remaining uninfected 2.5 months after birth found that only 49 of 902 babies (5.4 percent) breastfed for 3 to 36 months became infected.17
Some of the confusion that exists in determining the risk of transmission of HIV to the nursing infant may be due to the lack of effort by HIV researchers to define breastfeeding. Also, in much of the research the duration of breastfeeding may have been very short18, 19 and the degree of exclusivity unknown. Several authors have speculated that damage to the oral or intestinal mucosa which may occur with the introduction of other foods and liquids could facilitate infection of the infant from virus in the breast milk.20-23 The UN issued guidelines for decision makers, health care managers, and supervisors24-26 on how HIV-positive mothers should be advised to feed their babies in 1998, before any good studies had examined the possible impact of exclusive breastfeeding on postnatal MTCT. The first longitudinal study to do so found that exclusive breastfeeding in the early months of life led to no increased transmission compared to artificial feeding and may even have conferred a protective effect against transmission of HIV at delivery. At 3 months, 103 exclusively breastfed babies had a transmission risk (14. 6 percent) similar to 156 who had never been breastfed (18. 8 percent) and a statistically lower risk than 290 who had received other foods and liquids in addition to breast milk (24. 1 percent).27 Follow-up results at 15 months indicated that there was still no difference in transmission rates between infants who had been exclusively formula-fed during their first three months (19.4 percent) and those who had been exclusively breastfed (21.8 percent). There was still a higher rate of transmission among those who had received mixed feeding (28.2 percent).28
Although not breastfeeding will avoid all possibility of mother-to-child transmission of HIV through breast milk, the implications of this for child survival in the absence of breastfeeding pose major challenges and deserve close scrutiny. Guidelines need to be adapted to specific settings and to the circumstances of individual mothers, particularly those living in impoverished environments.
Very little is known about the impact of not breastfeeding in communities where breastfeeding is the cultural norm, for instance, in Africa. Scant attention has been paid to the social stigma of not breastfeeding, which would immediately identify a woman as HIV-positive, nor to the implications for increased fertility and population growth if the contraceptive effects of breastfeeding were no longer available to African women. Even with optimal hygiene, artificially fed infants suffer three to four times the rate of diarrheal infection of breastfed infants and have higher rates of respiratory, ear, and other infections.29 Where infectious diseases and malnutrition are the primary causes of death during infancy, artificial feeding substantially increases the risk of dying.16, 30 A recent WHO pooled analysis of data from developing countries found that infants who are not breastfed have a 6-fold greater risk of dying from infectious diseases in the first 2 months of life than those who are breastfed. It concluded that it will be difficult, if not impossible, to provide safe breast milk substitutes to children from underprivileged populations.31
Clearly, at this point in time, there is no conclusive answer for the individual HIV-infected mother wanting to know which feeding method is least risky for her infant. In particular, there is no research available to indicate the rate of transmission of HIV through breastfeeding in HIV-positive mothers who are undergoing antiretroviral treatment and among infants who also receive treatment at birth. It is likely to be low, particularly where mothers exclusively breastfeed, follow correct breastfeeding practices to reduce the risk of nipple damage, and where oral suction or other practices that might damage the infant's mucous membranes are avoided. Indeed, it will usually be possible to determine if the infant is in any case already HIV-infected before the period of exclusive breastfeeding ends with the addition of appropriate complementary foods to the infant's diet. If the infant is HIV-positive, breastfeeding could be continued.
In addition, HIV-positive women might want to consider expressing and treating their milk to deactivate its HIV content before feeding it to the infant. Sadly, the UN Guidelines were also issued before research had been done to develop and test simple methods for doing so, such as heating up the milk to a certain temperature or freezing it. Milk banks utilize Holder sterilization which involves maintaining the breast milk at 62.5 degrees for a half hour. Boiling will also deactivate the HIV, and though it will also destroy some components in the breast milk, boiled human milk remains more physiologically suited to the human infant than a formula prepared from animal milk.20
A diagnosis of HIV infection in the mother requires her to become informed as best she can and to make a very difficult decision on how to feed her baby. It need not automatically contraindicate the nutritional, immunological, and emotional benefits of breastfeeding for her baby. The UN Guidelines reiterate that HIV-positive mothers have the right to make informed decisions on how to feed their babies and health workers should support and assist them in whatever decision they make. However, HIV-positive mothers would be wise to inform themselves about existing local laws and health directives, since breastfeeding by an HIV-positive mother is a controversial issue, especially in developed countries such as the United States. Additional research is needed, along with careful reevaluation of programs that are arbitrarily stopping breastfeeding among HIV-positive mothers.
Pamela Morrison is a La Leche League Leader and IBCLC in private practice in Harare, Zimbabwe. She is also a Training Facilitator and Assessor for the Baby Friendly Hospital Initiative and on the ILCA Code Committee.
Ted Greiner is Research Advisor in International Nutrition at the Section for International Maternal and Child Health, Uppsala University, Sweden. He has been doing research related to the determinants of breastfeeding and breastfeeding program effectiveness since 1975.
1. Thiry, L. , S. Sprecher-Goldberger, T. Jonckheer et al. Isolation of AIDS virus from cell-free breast milk of three healthy virus carriers. Lancet 1985; 2(8583): 981.
2. Ziegler, J. B. , D. A. Cooper, R. O. Johnson, and J. Gold. Postnatal transmission of AIDS-associated retrovirus from mother to infant. Lancet 1985; 1:896-98.
3. Grosskurth, H. , F. Mosha, J. Todd et al. Impact of improved treatment of sexually transmitted diseases on HIV infection in rural Tanzania: Randomized controlled trial. Lancet 1995; 346:530-36.
4. John, G. C. , R. W. Nduati, D. Mbori-Ngacha et al. Genital shedding of human immunodeficiency virus type 1 DNA during pregnancy: Association with immunosuppression, abnormal cervical or vaginal discharge, and severe vita- min A deficiency. J Infect Dis 1997; 175:57-62.
5. Kreiss, J. , D. M. Willerford, M. Hensel et al. Association between cervical inflammation and cervical shedding of human immunodeficiency virus DNA. J Infect Dis 1994; 170:1597-1601.
6. Mofensen, L. M. Epidemiology and determinants of vertical HIV transmission. Semin Pediatr Infec Dis 1994; 5:253-65.
7. Wilfert, C. M. and R. E. McKinney. When children harbor HIV. Defeating AIDS: What will it take? Scientific American Special Report 1998.
8. John, G. C. and J. Kreiss. Mother-to-child transmission of human immunodeficiency virus type 1. Epidemiol Rev 1996; 18(2):149-57.
9. Newell, M. L. , G. Gray, and Y. J. Bryson. Prevention of mother-to-child transmission of HIV-1 infection. AIDS 1997; 11(suppl A):S165-72.
10. Centers for Disease Control. Administration of zidovudine during late pregnancy and delivery to prevent perinatal HIV transmission, Thailand, 1996- 1998. Morbid Mortal Weekly Rep 1998; 7(8):151-54.
11. Guay, L. A. , P. Musoke, T. Fleming et al. Intrapartum and neonatal single-dose nevirapine compared with zidovudine for prevent of mother-to-child transmission of HIV-1 in Kampala, Uganda: HIVNET 012 randomised trial. Lancet 1999; 354:795-802.
12. Preble, E. A. and E. G. Piwoz. HIV and infant feeding: A chronology of research and policy advances and their implications for programs 1998. The Linkages Project and the Support for Analysis and Research in Africa (SARA) Project, the Academy for Educational Development, USAID Bureau for Africa.
13. Simonon, A. , P. Lepage, E. Karita et al. An assessment of the timing of mother-to-child transmission of human immunodeficiency virus type 1 by means of polymerase chain reaction. J Acquired Immune Deficiency Syndromes 1994; 7(9):952-57.
14. Van de Perre, P. Postnatal transmission of human immunodeficiency virus type 1: The breastfeeding dilemma. Am J Obstet Gynecol 1995; 173(2):483-87.
15. Dunn, D. T. , M. L. Newell, A. E. Ades, and C. S. Peckham. Risk of human immunodeficiency virus type 1 transmission through breastfeeding. Lancet 1992; 340(8819):585-88.
16. Cutting, W. A. Breastfeeding and HIV: A balance of risks. J Trop Pediatr 1992; 40(1):6-11.
17. Leroy, V. , M. -L. Newell, F. Dabis et al. International multicentre pooled analysis of late postnatal mother-to-child transmission of HIV-1 infection. Lancet 1998; 352:597-600.
18. Italian Register for HIV infection in children. Human immunodeficiency virus type 1 infection and breast milk. Acta Paediatr (suppl)1994; 400:51-58.
19. Gabiano, C. , P. A. Tovo, M. de Martino et al. Mother-to-child transmission of human immunodeficiency virus type 1: Risk of infection and correlates of transmission. Pediatrics 1992; 90(3):369-74.
20. Morrison, P. HIV and infant feeding: To breastfeed or not to breastfeed. The dilemma of competing risks, part l. Breastfeeding Review 1999; 7(2):5-13.
21. Greiner, T. The HIV challenge to breastfeeding. Breastfeeding Review 1999; 7(3):5-9.
22. Hormann, E. Breastfeeding and HIV. Breastfeeding Review 1997; 5(2):21-24.
23. Arnold, L. D. W. Currents in human milk banking. HIV and breast milk: What it means for milk banks. J Hum Lact 1993; 9(1):47-48.
24. UNAIDS/UNICEF/WHO. HIV and infant feeding: Guidelines for decision-makers, 1998 . WHO/FRH/CHD/98.1.
25. UNAIDS/UNICEF/WHO. HIV and infant feeding: A guide for health care managers and supervisors, 1998 . WHO/FRH/CHD/98.2.
26. UNAIDS/UNICEF/WHO. HIV and infant feeding: A review of HIV transmission through breastfeeding, 1998. WHO/FRH/NTU/CHD/98.3.
27. Coutsoudis, A. , K. Pillay, E. Spooner et al. Influence of infant-feeding patterns on early mother-to-child transmission of HIV-1 in Durban, South Africa: A prospective cohort study. Lancet 1999; 354:471-76.
28. Coutsoudis, A. Presentation at Second Conference on Global Strategies for the Prevention of HIV Transmission from Mothers to Infants. September 3, 1999, Montreal, Canada.
29. Walker, M. A fresh look at the risks of artificial infant feeding. J Hum Lact 1993; 9(2):97-107.
30. Feachem, R. G. and M. A. Koblinsky. Interventions for the control of diarrhoeal disease among young children: Promotion of breastfeeding. Bull WHO 1984; 62(2):271-91.
Collaborative Study Team. On the role of breastfeeding on the prevention
of infant mortality. Effect of breastfeeding on infant and child mortality
due to infectious diseases
in less developed countries: A pooled analysis. Lancet