Breastfeeding and HIV/AIDS: is there a conflict?

Prof. R. V. Short
Department of Obstetrics and Gynaecology, University of Melbourne
Royal Women’s Hospital, Carlton, 3053

August 1st, 2003 marked the beginning of World Breastfeeding Week, and in a circular to commemorate the event Gro Harlem Brundtland, the former Director-General of the World Health Organization said:

“The HIV pandemic and the risk of mother-to-child transmission of HIV through breastfeeding continues to pose unique challenges to the promotion of breastfeeding, even among unaffected families. Accurate information, disseminated widely, about breastfeeding’s benefits for the majority of children and mothers is essential for preventing baseless doubts in this connection. Support for HIV-positive women should include counseling about appropriate infant-feeding options”.

That is a perfect summary of our dilemma. Speaking in Paris on July 14th, 2003, at the United Nations Global Fund to fight AIDS, Nelson Mandela said that AIDS was “The greatest health crisis in human history”. He went on to point out that “we have failed to translate our scientific progress into action where it is most needed, in the developing world”. How right he was.

The frightening facts

In some Southern African countries, e.g. Botswana and Lesotho, over 40% of pregnant women are HIV-positive; in Swaziland, Zambia and Zimbabwe, over 30% are HIV-positive (UNAIDS, 2002).

When considering mother-to-child transmission of HIV, this ranges from 14-32% in Europe and the United States, to 25-48% in Sub-Saharan Africa, and the difference is thought to be due to breastfeeding (De Cock et al, 2000). 1,600 HIV-positive children a day are born in Sub-Saharan Africa.

Globally, at the end of 2001, there were 14 million AIDS orphans under the age of 15 who had lost one or both parents to AIDS. (UNAIDS, 2002).

Since about 40% of mother-to-child transmission of HIV is thought to be due to breastfeeding, the simple solution might appear to be to recommend that no HIV positive mother should breastfeed. But in a developing country, such a recommendation would have disastrous consequences. In the first place, many women will never know whether they are HIV positive, so you would have to recommend that no woman breastfed her baby. But the risk of an infant dying from infectious diseases in the first two months of life is six times greater for infants who are not breastfed. Thus the promotion of infant formula feeding to reduce HIV infection may increase overall infant morbidity, mortality and malnutrition.

A recent analysis of mother-to-child transmission in mothers breastfeeding for 18-24 months suggests that intrauterine infection accounts for 5-10% of transmissions, 10-20% occur during the birth process, and can be reduced by caesarean delivery, or antiretroviral treatment (e.g. Nevirapine) of the mother and the neonate, 5-10% occurs in the first 2 months of breastfeeding, and a further 5-10% during subsequent breastfeeding, giving an overall mother-to-child transmission rate of 25-50% (De Cock et al, 2000).

Why Breast is still Best

The situation has now changed for the better, with the exciting discoveries made by Prof. Coovadia and his team from Durban, South Africa (Coutsoudis et al, 2001). In a large prospective study of HIV-positive women who chose to either breastfeed or bottlefeed their babies, 118 infants that were exclusively breastfed for the first 6 months of life had NO increased risk of acquiring HIV infection compared to 157 infants not given any breastmilk. However, 276 infants who were on mixed breast and bottle feeding from birth had a significantly higher rate of HIV infection.

After 6 months, when the exclusively breastfed babies started to go on to mixed feeding, their rates of HIV infection started to rise significantly when compared to babies who were never breastfed. The explanation for this surprising finding appears to be related to the viral load in the breastmilk, which determines its infectivity.

With the approach of weaning, or if there is any sub-clinical mastitis, the white cell count in the milk and hence the viral load is increased, making it much more infectious to the baby (Willumsen et al, 2003).

The conclusion is obvious. In a developing country setting, all mothers should be encouraged to breastfeed exclusively for at least the first 6 months, regardless of their HIV status, and then to wean the baby rapidly. Research needs to be done to see what would be the cheapest and most available weaning food to use.

HIV Prevention during breastfeeding

Of course, the central issue remains – how to protect the mother from becoming infected with HIV in the first place. Here there is a sad twist to the tale that involves breastfeeding. In West Africa, and maybe elsewhere, there are cultural taboos on intercourse during the first 6 months of lactation. Unfortunately this means that this is the time when male partners are most likely to seek satisfaction from extra-marital sex, and hence become infected with HIV. Since viral titres are extremely high during the early stages of the infection, this means that the men may be highly infectious once they resume intercourse with their lactating partners, who in turn will be much more likely to infect their babies in the early stages of their own infection. Thus men need to be made aware of the fact that extra-marital sex whilst their partners are lactating puts three lives at risk – their own, their partner’s, and their baby’s. If ever there was a time for men to practice Safe Sex, surely this is it.

A Counsel of Perfection for the HIV+ Mother

We can now begin to summarize the situation. Leaving aside the key question of how to avoid HIV infection, what should a woman do about it once she is infected?

The first thing is to consider very carefully the issues around parenting. Since HIV infection is in effect a death sentence for the mother, even in developed countries, is it right to bring a new child into the world, only to become an AIDS orphan when the mother dies?

If the HIV positive mother does not wish to become pregnant, and wants to minimize the risk of infecting her partner if he is HIV negative, what contraceptive should she use? This is a question that is seldom addressed, and there is no easy answer. If she becomes pregnant against her wishes, then perhaps she should seriously consider having an abortion.

If she decides to continue with the pregnancy, she can minimize the chance of infecting her baby at birth, the time of greatest risk, when the baby may swallow infected maternal blood and secretions, by having a Caesarean delivery. Alternatively she can have antiretroviral treatment, e.g. Nevirapine, for herself antenatally and for the baby immediately after birth. The chances of being able to afford a Caesarean, or having access to antiretrovirals in the developing world are minimal.

The mother should breastfeed her baby exclusively for the first 6 months of its life as this will give it the best possible protection against diarrhea and respiratory infections, and there is little or no further risk of HIV transmission. But if she develops mastitis, she should cease breastfeeding immediately. After 6 months, the baby should be abruptly weaned from the breast, and introduced to solid food. By adopting this all-or-nothing breastfeeding policy, mother-to-child HIV infection should be drastically reduced.

Future prospects

The HIV pandemic is destined to get much worse before things start to improve. At the end of 2001 there were 40 million people living with HIV/AIDS, 2 million of whom were women. There were 5 million new infections, and 3 million deaths from AIDS, including 580,000 children (UNAIDS, 2002).

Although Sub-Saharan Africa is the epicenter of the epidemic, with 28,500,000 infections, South and South East Asia come next with 5,600,000 infections. It seems likely that India will soon become the new epicenter, and by 2050 some estimates suggest that globally, over 1 billion people will be infected.

Stopping HIV infection must be the world’s first priority, and reducing mother-to-child transmission should be high on the list; here it seems that the promotion of exclusive breastfeeding has an important role to play.

References

De Cock et al (2000). Prevention of mother to child HIV transmission in resource-poor countries. J. Amer. Med. Assocn. 283, 1175-1182.

Coutsoudis, H. M. et al (2001). Method of feeding and transmission of HIV-1 from mothers to children by 15 months of age: prospective cohort study from Durban, South Africa. AIDS 15, 379-387.

UNAIDS (2002). Report on the global HIV/AIDS epidemic. Geneva.

Willumsen, J. F. et al (2003). Breastmilk RNA viral load in HIV-infected South African women: effects of subclinical mastitis and infant feeding. AIDS 17, 407-414.

ABC TV - The World Today - August 4, 2003
HIV positive mothers in Africa encouraged to breastfeed their children

ELEANOR HALL: While Africa battles to contain the AIDS pandemic, there's new research about the impact of breastfeeding on the rate of mother-to-baby infections. The research concludes that it's vital that women who are HIV positive breast feed exclusively, rather than provide bottle formula to their newborns, as Toni Hassan reports.

TONI HASSAN: It's a staggering statistic: In Africa today, 40 per cent of all mothers reported to hospitals and clinics are HIV positive. Mother-to-child transmission rate ranges between 25 and 50 per cent.

Up to 10 per cent of those infections occur in the womb – something practitioners can't do anything about. Another 10 to 20 per cent occur at birth, probably due to blood-to-blood contact.

Caesarean delivery can reduce that, but that's not an option for women in the developing world. New mums and their babies could also be given anti-retroviral drugs, but again it's often not an option.

Another 10 to 20 per cent of transmissions occur during breastfeeding. But that, according to Roger Short, a specialist in reproduction and AIDS at Melbourne University that does not mean advocating a ban on breastfeeding.

Dr Short has been liasing with colleagues in Durban, South Africa who've done some ground breaking research in the area. The conclusion: breast milk, exclusively offered, is still best.

ROGER SHORT: Mothers who breast feed exclusively and don't give the baby any food other than breast milk – none of them become infected through the breast feeding. But if the mothers start to introduce supplements and infant formula, then up goes the transmission rate, and this completely unexpected result is explained by the fact that once you start partially breastfeeding and topping up with supplements, the load of virus in the breast milk shoots up.

And so the recommendation we've now got to make is that we should reinforce the World Health Organisation's recommendation that all mothers should breast feed for at least six months exclusively, giving nothing else. And then, when you decide to wean, you must wean very rapidly, because it's the process of weaning that, paradoxically, is infecting the babies.

TONI HASSAN: WHO's initial recommendation that women in the developing world are encouraged to breast feed – is that even being heard?

ROGER SHORT: Well, I think it's not, unfortunately. The obvious response when people heard there was infection occurring through breast milk was oh, right, we've got to go onto 100 per cent infant formula.

But when we actually look at the statistics, I mean it leaves absolutely no doubt that putting babies onto exclusive infant formula kills them, because they going to die of diarrhoea.

TONI HASSAN: Because there's a bigger problem isn't there, that women in the developing world are tempted to use formula because it's seen as something developing women use, despite the fact that the water is obviously more unsafe and therefore the chance of passing on any sort of infection is greater.

ROGER SHORT: The difficulty of making up infant formula safely in a developing country setting is enormous, and sadly there's a new twist to that. When I was in South Africa at the end of last year, they told me that because of the enormous deforestation that's occurred, chopping down trees to make coffins, there's no firewood left – the coffins for the babies and adults who had died of AIDS.

TONI HASSAN: So water isn't even being boiled?

ROGER SHORT: No.

TONI HASSAN: Well, the challenge is huge, isn't it.

ROGER SHORT: It's enormous.

ELEANOR HALL: Indeed it is. Professor Roger Short, a specialist in reproduction at Melbourne University speaking to Toni Hassan.