Continued...

HIV infected mothers and breast feeding

Most studies have shown that there is 14% extra risk of HIV transmission by breast milk, which means that it almost doubles the rate of vertical transmission. The risk depends on various factors. Colostrum has higher viral load and higher risk of infection. But it also contains higher antibody level. The risk is increased by obvious contamination by maternal blood due to cracked or sore nipple. But the most important factor is the length of breast feeding.

There is a cumulative increase in transmission of HIV, as length for which breast feeding continues, as shown in Mallsai study done in 1999. The risk was estimated to be 0.7% per month for 0-6 months i.e. cumulative risk of 4.2% in this period. It was 0.6% per month between 6-12 months i.e. cumulative risk of 3.6% during this period. It decreased to 0.3% per month between 12-18 months i.e. cumulative risk of 5.8% in this period and 0.2% per month between 18-26 months i.e. cumulative 1.2% for that period. The total cumulative risk is 10.2% if breast feeding is continued till 2 years and is 4.2% if breast feeding is continued for 6 months. Hence it will be optimal to exclusively breast feed till 6 months and then abruptly wean off completely in next 10-15 days

Exclusive breast feeding will avoid problems of infection related with top feeding. It is cost effective, ideal in developing countries. It will also avoid stigma associated with not breast feeding due to HIV. It is accepted by > 90% in developing countries. However, as discussed later mixed feeding should be avoided and the compliance to absolutely exclusive breast feeding in general population is estimated to be only 22-35%. Hence it is the duty of counselor and pediatrician to ensure that it is exclusive breast feeding and not mixed feeding.

HIV and replacement feeding (RF)

Replacement feeding may appear as a logical choice in HIV infected mothers. However, it has its own problems. Replacement feeding, especially bottle feeding, is associated with higher infections like ARI and diarrhea, especially in countries with high IMR. A study in Brazil showed that the overall mortality due to ARI was 4 times more and that due to diarrhea 14 times more in top-fed babies as compared to breast fed babies. A recent study done in South Africa compared babies born to HIV positive mothers who were breast fed with those who were formula fed. This was done in urban set up with UFMR of 70/100,000. The mothers were educated to an average of 8th standard and they all had access to safe water supply. This was very similar settings as ours. 2 year follow up results showed that the transmission of HIV at 2 years was 19.1% in formula fed babies and 35.7% in breast fed babies, yet the mortality at 2 years was 20% in formula fed babies and 24.4% in breast fed babies. This proves that the gains in form of less HIV infection in top fed babies was set off by higher mortality due to ARI and diarrhea in both HIV infected and non-infected babies.

Besides this there is problem of breast milk spillage and leakage if mother chooses to give replacement feeds. There is social stigmatization if the mother does not breast feed the baby in countries where breast feeding is the norm. It also involves issues of education of mother, socio-economic condition, and access to potable water to make safe and correct replacement feeds. Lastly, comes the question of affordability. Individually the mother may tend to make diluted feeds which is dangerous. At national level in India, it will be enormous task to spend 75 million rupees per month to provide formula feeds to all babies born to HIV positive mothers. Hence if the mother chooses not to breast feed it is better to give cow's milk with spoon rather than formula feeds as it is cheaper, easily available and more acceptable. One should again ensure 'exclusive' replacement feeding if mother chooses it and not mixed feeding.

HIV and mixed feeding

A study done in Durban, South Africa in 1999 compared HIV transmission in exclusively breast fed babies, exclusively top fed babies and babies given mixed feeding i.e. babies given breast feeds plus any other liquids, born to HIV infected mothers. The results at 3 months showed that the HIV transmission was 14.6% in exclusively breast fed babies, 18.8% in exclusively top fed babies, and 24.1% in babies given mixed feeding. At this stage, it appeared that the transmission was less in exclusively breast fed babies than in exclusively top fed babies and both were significantly better than mixed feeding. Long term follow up results at 15 months showed that HIV transmission was 24.7% in exclusively breast fed babies, 19.4% in exclusively top fed babies and 35% in babies given mixed feeding. This showed that over long term the advantage of exclusive breast feeding seems to be negated as compared to exclusive top feeding. However both were significantly better than mixed feeding.

HIV is absorbed via the gut of newborn. A baby on top feeding has leaky gut allowing increased chance of HIV absorption. Hence a child who is on mixed feeding will have worst outcome. Besides such a child is exposed to evils of both HIV as well as other infections related to top feeding. Hence, HIV infected mother should not give mixed feeding. If she decides to breast feed, it should be exclusive breast feeding and if she decides to give replacement feeding, it should be exclusive replacement feeds.

Policy

Policy regarding infant feeding by HIV infected mothers at individual level and at national level should take into consideration- the merits and the demerits of breast milk replacement feeds, education level, socio-economic status, health statistics, accessibility to safe water, affordability and HIV prevalence. It should be informed choice by the mother. The role of counselor and pediatrician should be to give correct information on various options and they should not be biased or judgmental towards any option. The informed choice taken by mother should be respected even if it appears incongruent socio-economically. In west mothers prefer not to breast feed. In India, the choice should be left to mother. But whatever is the choice it should be either exclusive breast feeding or exclusive replacement feeding and not mixed feeding.