American Centre for Disease Control (CDC) in collaboration with Kenya Medical Research Institute (Kemri) are carrying out a study on the use of ARV combination therapy that would enable HIV positive pregnant women who are exclusively breastfeeding to significantly reduce the risks of passing the virus to their babies.

“We are seeing exciting results that are likely to work for the good of the women. But I cannot give you the detailed statistics because we are yet to finish analyzing the data,” says Tim Thomas, Head of HIV research Branch at the Kemri research station in Kisumu.

According to Thomas, they expect to reduce by 50 percent the transmission rates achieved when nevirapine is used as a single dose to prevent the mother from passing the virus to her baby.

It is estimated that between 10 and 20 percent of the infants get infected by HIV through breast feeding if breast feed for 18 to 24 months.

At the moment, studies in African countries have also shown that when nevirapine is given as a single dose to HIV positive women on onset of labour, chances of a mother passing the virus to the baby are reduced from 40 to 12 percent.

The CDC/Kemri study wants to reduce this figure further to 6 percent, significantly cutting down the possibility of the child getting infected.

To enable an HIV positive woman prevent herself from passing the virus to her baby before and after birth during breast feeding time, ARV drugs are administered when the pregnancy is 33 weeks old and just before the onset of labour.

Women with CD4 counts more than 250 are given Combivir and Nelfinavir drugs, while those with the counts less than 250 are given Combivir and Nevirapine. So far, 75 per cent of the women enrolled have CD4 counts more than 250.

Those taking the drugs continue do so for another six months after delivery, during which they freely carry on with exclusive breast feeding.

Insistence on exclusive breast feeding is important because it improves the outcomes of reduced transmissions.

In a study conducted in South Africa, HIV-positive mothers who reported exclusive breastfeeding for at least three months were found to be less likely to transmit the virus to their infants than mothers who introduced other foods or fluids before three months.

The use of drugs in the CDC study are therefore designed to reduce the amount of the virus in the woman’s body, enabling those doing exclusive breast feeding to significantly reduce the chances of passing the virus to the child.

Once the six months are over and their CD4 counts are more than 200, the woman is stopped from both taking the drugs and breast feeding.

They are however followed-up to two years to monitor how the CD4 counts are performing.

On the other hand, those with CD4 counts less than 200 by the end of six months only stop breast feeding, but continue being on the regimen up to two years.

For babies born to these mothers, treatment intervention is introduced once the PCR tests indicate they are HIV positive.

To make the intervention successful, mothers are advised not to do any breastfeeding after stopping medication. They are prepared to start introducing their babies to solid foods when they are five and half months old.

This is designed to help them gradually introduce the baby to solid foods and other fluids and not wean abruptly when breast feeding stops.

For those mothers who, because of other factors may delay weaning their babies by the six month, they are usually give them drugs for an extra two weeks to enable them wean the baby.

But it has not been rosy for those conducting the study. So far 24 pregnant women who were screened and put on the drugs have withdrawn from the study before completing the drug intervention.

Researchers in the study are worried that these women have either been discouraged by their husbands or other family members to continue in the study. Those interviewed cited their husbands as being key persons in the decision they made.

Indeed, preliminary findings are showing that women visiting Prevention of Mother to Child Transmission of HIV programme are failing to honour future visits after receiving threats or being discouraged by their husbands.

This might explain why 214 women who had been counseled and referred for screening in the CDC/Kemri failed to come for their appointments when their pregnancy was 33 weeks old.

“Although we ask women to come along with their husbands during the antenatal clinics as a way of getting the support of the husband, it is not mandatory,” says Thomas.

In the past, organizations that have tried to make it mandatory for women to be accompanied by their husbands when coming for antenatal or post-natal care have seen the requirement backfire.

Many of the women either stopped coming for subsequent visits or did not choose to go to such centres in the first place.

This is now forcing those working in this area to rethink the approach so as to capture as many HIV positive women as they can and save the lives of many children.

Still, there is ray of hope. Researchers in the Kisumu study are upbeat that a number of the 348 women who are still participating in the study are being accompanied by their husbands when they come for antenatal and post-natal clinics.

Besides the drop-outs, Dr Thomas says the study was early last year temporary suspended after the US Food and Drug Administration (FDA) reported that females and patients with higher CD4+ cell counts had a 12 fold increased risk of liver toxicity when they used nevirapine.

“The Indications and Usage section of the Viramune label now recommends against starting nevirapine treatment in women with CD4+cell counts greater than 250 cells/mm3 unless benefits clearly outweigh risks,” said FDA in a Public Health Advisory for Nevirapine (Viramune) issued in January last year.

“This recommendation is based on a higher observed risk of serious liver toxicity in patients with higher CD4 cell counts prior to initiation of therapy,” it adds.

In the Kisumu study, where Nevirapine was being used, Thomas says: “We had seen some of these side-effects in our volunteers, but they were not serious among those women who were using nevirapine. So we had to take sometime and change them to another regimen.”

It is after this that women being enrolled in the study and whose CD4 counts are more than 250 are not being given nevirapine.

This finding is likely to be critical to the government’s ARV policy where nevirapine is one of the other two drugs – stavudine and lamivudine- that are used as first line ARVs in Kenya for all people living with Aids.

The national guidelines do not however warn people who have attained high CD4 counts against using nevirapine.

For now, many people are keenly watching the CDC study because of the social and economic implications of results it will come up with.

Majority of the HIV positive women have had rough time from their family members once they decide to follow some doctors advise not to breast their children if it is not exclusive breastfeeding. But to instead feed them using substitutes of breast milk such as formula milk.

In the African cultural context, where a mother’s milk is considered as the best for the baby, failure to breast feed raises serious questions about the mother. Intense stigma surrounds formula milk, as many questions are asked about a woman who uses it in place of breast milk.

This has tended to make women abandon the doctor’s advice and breast feed and provide the child with other foods just to please the family members, while at the same time putting the baby at a greater risk of infection.

But even where the family is receptive to use breast milk substitutes, they may be too poor to provide quality and safe food alternatives or lack access to clean water.

Indeed research has shown that where there are no resources to give quality breast milk substitutes, then the artificial feeding can triple the risk of infant deaths. This makes breast milk the best way out in such settings.