In many countries HIV- positive women are told to prevent transmission of the virus to their newborn child by giving them food other than breast milk. But in India, infants denied breast milk may be at risk of malnutrition as well as serious food borne infections. So, what are the risks and benefits of breastfeeding?

Mother-to-child transmission (MTCT) of HIV is the most significant route of transmission of HIV infection in children below the age of 10 years.

Such transmission can occur during pregnancy, at the time of delivery, and after birth through breastfeeding.

Based on a compilation of studies, it is estimated that, without any anti-retroviral intervention, 15% to 30% of babies born to HIV positive women will acquire the infection—if the women do not breastfeed their children. If they breastfeed their children up to six months, 25% to 35% of children will become positive. If they breastfeed up to 24 months, 30% to 45% babies will become positive.

Why do we believe that HIV is transmitted through breast feeding?
In 1985, an Australian team (Ziegler and colleagues) described the case of an HIV-1-infected infant who acquired the infection during breastfeeding. His mother had been HIV negative at the time of her delivery but received a transfusion of HIV-1-contaminated blood after delivery. This report was confirmed by other case reports from around the world. It is also known that transmission rates are generally higher in countries where breastfeeding is traditional compared with countries where breastfeeding by HIV-1-infected women is unusual. Further, several studies report higher rates of HIV-1 infection among breastfed children compared with formula-fed children.

What is known about HIV transmission through breastfeeding
HIV-1 can be detected in human milk from HIV-1-infected women; in one study the prevalence was higher in mature milk (47%) than in colostrum (27%). A higher human milk viral load is associated with a higher risk of mother-to-child transmission. Similarly, a higher plasma viral load is associated with higher probability of breastfeeding transmission per litre of milk ingested by the infant.

Risk factors for transmission of HIV-1 through breastfeeding
Timing of maternal infection: Mothers who become infected when they are breastfeeding are nearly twice as likely to transmit the virus to their baby, compared to those infected before or during pregnancy.

Duration of breastfeeding: Longer duration of breastfeeding is associated with an increased risk of transmission. In a study conducted in Malawi, the cumulative risk of infection for infants of HIV-1-infected mothers continuing to breastfeed after 1 month of age was 3.5% at the end of 5 months, 7.0% at the end of 11 months, 8.9% at the end of 17 months, and 10.3% at the end of 23 months.

Pattern of breastfeeding: A study in South Africa (Coutsudis) suggested that feeding patterns could also have an influence on the chances of transmitting HIV. Researchers found little difference in transmission risk between mothers who breastfed for three months and those who did not breastfeed at all. They also found that infants exclusively breastfed for between three and six months were less likely to become HIV- positive than those who received mixed feeding during that period.

One possibility is that in mixed breastfeeding contaminated food damaged the infant’s bowel and facilitated the entry of HIV-1 into tissues. This suggests that in situations where mothers cannot be assured of a clean water supply exclusive breastfeeding for 3 to 6 months may be a better option: it is affordable, culturally acceptable, good for the child, and -- when compared to mixed feeding -- reduces mother-to-child transmission of HIV.

Stage and progression of maternal illness: The stage of the mother’s HIV disease as measured by CD4 count, RNA viral load in plasma, or the presence of clinical symptoms and systemic infections, also affect the rate of transmission.

Other factors: The mother’s breast health -- subclinical mastitis, breast abscess, fissured nipples -- as also problems like oral thrush or intestinal lesions in the baby, have been identified as contributors to mother to child transmission (MTCT).

Recommendations from the World Health Organisation
Earlier consensus statements from the World Health Organisation (WHO) recommended that breastfeeding should be advised for all women, including HIV-1-infected women, in areas of the world where most infant deaths were attributable to infections and malnutrition. Where infectious diseases were not the main causes of infant death, HIV-1-infected women were advised not to breastfeed but to use safe feeding alternative(s).

Revised recommendations in the 1990s
In 1997 and 1998, WHO, UNICEF and UNAIDS issued joint revised guidelines recommending that all women be given access to HIV-1 counselling and testing as well as the information allowing them to make fully informed decisions regarding infant feeding. In other words, the decision to breastfeed was now based on the mother’s HIV status as well as the availability of clean water.

Current United Nations and WHO infant feeding guidelines
These guidelines were revised yet again in 2003. Recognising the need to minimise the risk of MTCT to infants while simultaneously avoiding increasing the risk of other morbidity and mortality due to malnutrition and infection, WHO, UNAIDS and UNICEF issued the following recommendations:

“For mothers who are HIV negative or do not know their HIV status, exclusive breastfeeding for the first six months and continued breastfeeding for up to two years or longer with addition of complementary food after six months is recommended.

“However if a woman has tested positive for HIV and when replacement feeding is acceptable, feasible, affordable, sustainable and safe, avoidance of all breastfeeding by HIV-infected mothers is recommended.

“Otherwise, exclusive breastfeeding is recommended during the first months of life and should then be discontinued as soon as feasible…When HIV-infected mothers choose not to breastfeed from birth or (choose to) stop breastfeeding later, they should be provided with specific guidance and support for at least the first two years of the child’s life to ensure adequate replacement feeding.”

Some facts about breastfeeding
Exclusive breastfeeding is giving only breast milk, directly or expressed - from the mother or a wet nurse - and no other liquids or solids with the exception of drops or syrups consisting of vitamins, mineral supplements, or medicines.

Benefits of breastfeeding
Breast milk provides complete nutrition for an infant for the first six months of life. It contains nutrients that other feeds may not provide include high-quality protein, long-chain polyunsaturated fatty acids needed for the infant’s developing brain and eyes, and micronutrients including iron in a form in which they are efficiently absorbed. Mothers’ milk contains anti-infective factors that protect babies from a variety of infections, and growth factors that stimulate the development of the infant’s gut. Breastfed infants have lower rates of diarrhoeal diseases, pneumonia, ear and other infections compared to artificially-fed infants. They also have lower risks of certain chronic diseases in later life. Breastfeeding promotes bonding between mother and child. Further, exclusive breastfeeding gives the mother more than 95% protection against pregnancy for the first six months after the birth of her baby. Finally, it protects her against certain cancers like breast and ovarian cancer.

Risks of breastfeeding for an HIV-positive mother
On the other hand, breastfeeding by an HIV-positive mother increases the risk of her transmitting HIV to the child. This is more so if the mother acquired HIV infection after delivery, or if she has a breast infection. The risk of transmission is further increased if the family pressurises the mother to give the infant other liquids or food.

Breastfeeding options for an HIV-positive mother
Women may use these feeding options at different points in their babies’ development, and will need special support at each of the phases. At all stages cup feeding is recommended over bottle-feeding.

Exclusive breastfeeding with weaning at or before six months limits exposure to HIV while giving the child the benefits of breastfeeding. The transition from exclusive breastfeeding to exclusive replacement feeding should be minimised; mixed feeding might increase the risk of HIV transmission. It may help to get the infant to drink expressed breast milk from a cup or spoon. Avoid offering the breast to comfort a distressed child.

HIV-positive mothers can express their milk and heat it to kill the virus. Place the container of expressed milk in a larger container of water heated to boiling point and let it remain there for 15 to 30 minutes.

Have another HIV-negative woman breastfeed the infant. The wet nurse must be available to breastfeed the infant frequently throughout the day and night and she must protect herself from HIV infection as long as she is breastfeeding.

Use human milk banks, centres where donor milk is pasteurised and made available for infants.

Infants who are receiving no breast milk should be given replacement feeding, a diet providing all the necessary nutrients until they can be fully fed on family foods. During the first six months of life, this consists of suitable breast-milk substitute. After six months other foods should be added.

Replacement feeding

Options for replacement feeding include commercial infant formula - specially formulated milk made specifically for infants and sold in shops or provided through programmes designed to prevent HIV transmission to infants. You can also use fresh or processed animal milk that is modified by adding water, sugar and micronutrient supplements.

Replacement feeding ensures that there is no risk of transmitting HIV to the infant through feeding. Other family members can help feed the infant. Commercial formulas include most of the nutrients that the infant needs. Home prepared modified animal milk formula is less expensive than commercial formula.

However, replacement feeding is expensive, time-consuming to prepare fresh for each feed, requires clean boiled water and may not always be available. The mother or caretaker must make fresh replacement milk for each feed both day and night. Home prepared formula does not contain all the nutrients that infants need. Finally, replacement feeds do not contain antibodies to protect the baby from infection.

How should an HIV-positive woman decide between breastfeeding and replacement feeding?
According to current guidelines if a pregnant woman tests positive for HIV and if replacement feeding is acceptable, feasible, affordable, sustainable and safe, she should not breastfeed at all.

Acceptable: The mother is supported by the family and community in replacement feeding – or she will be able to cope with pressure to breastfeed – and she can deal with any stigma attached to being seen with replacement food.
Feasible: The mother (or family) has adequate time, knowledge, skills and other resources to correctly prepare replacement food and feed the infant up to 12 times in 24 hours.
Affordable: The mother and family, with community or health-system support if necessary, can afford the cost of purchasing/producing, preparing and using replacement feeding, including all ingredients, fuel, clean water, soap and equipment, without compromising the health and nutrition of the family. This includes access to and cost of medical care if necessary.
Sustainable: There is a continuous supply for all ingredients and products needed for safe replacement feeding, for as long as the infant needs it.
Safe: Replacement foods are correctly and hygienically prepared and stored, and fed in nutritionally adequate quantities, with clean hands and using clean utensils, preferably by cup.

Counselling: translating the guidelines into clinical practice
The HIV-positive mother should receive counselling, which includes information about the risks and benefits of various infant feeding options, guidance in selecting the option most likely to be suitable for her situation, and support in her choice. Good counselling can assist HIV-infected women select and adhere to safer infant feeding options appropriate for their situation. It may also help to reduce breast problems which could increase the risk of HIV transmission through breastfeeding.

In the Programme for Prevention of Parent to Child Transmission, infant-feeding counselling should be provided during the antenatal as well as postnatal period to all HIV-positive mothers and those whose HIV status is unknown. Counselling on complementary feeding should also be provided once the baby is four to six months old.

Take-home points

• There is a 5-20% (average of 14%) risk of transmission of HIV from mother to baby.

• All HIV positive mothers should be counselled in the antenatal and postnatal period regarding choices in infant feeding.

• When replacement feeding is acceptable, feasible, affordable, sustainable and safe, avoidance of all breastfeeding by HIV-infected mothers is recommended.

• Otherwise, exclusive breastfeeding is recommended during the first months of life. Breastfeeding should be discontinued as soon as feasible, taking into account the mother’s situation and the risks of replacement feeding (including infections other than HIV and malnutrition).

• When HIV-infected mothers choose not to breastfeed from birth or stop breastfeeding later, they should be provided with specific guidance and support for at least the first two years of the child’s life to ensure adequate replacement feeding.

Bibliography

(Dr Jayashree A Mondkar is professor and head of the department of neonatology, LTMG Hospital, Sion, Mumbai)

Infochange News & Features, February 2008