Drugs could prevent HIV transmission

It is known that women who take anti-HIV drugs during labour significantly reduce their chances of passing the virus on to their babies.

However, research by US and Ugandan doctors has found that taking a certain drug just once could offer protection.

The move could prevent hundreds of thousands of infections each year, they write in the Lancet medical journal.

The number of HIV positive pregnant women in Africa is estimated at three million - and there is a significant risk of the virus being passed on to the baby as it comes into contact with blood and body fluids during birth.

To combat this, it is recommended that the mother, even if she is not regularly taking antiretroviral drugs, takes a course of therapy during labour, and the baby is given the same drugs early in life.

Repeated problem

The key is the number of times that the drug has to be given to the new baby.

Other treatments, such as AZT, have to be given every day for at least a week after birth, as well as every three hours to the woman in labour.

If widely implemented, this has the potential to prevent several hundred thousand new infections every year. Dr Brooks Jackson, Johns Hopkins University

This makes it much more unlikely that the full course of treatment will be completed - both because it will cost more, and because it will be far less convenient for a mother who wants to take her child away from hospital.

However, the researchers from Johns Hopkins University in the US and Makarere University in Kampala, Uganda, tested a new regime, involving a drug called nevirapine - also known as Viramune.

Drug firm Boehringer is supplying the drug free to South Africa to help prevent HIV spread.

The drug is given just once to the mother during labour, and just once to the baby once it is born.

In tests, more than 600 babies and mothers were given either AZT or nevirapine.

The transmission rate using nevirapine was lower - after six to eight weeks, 59 babies in a group given AZT were HIV positive, compared with only 36 in the nevirapine group.

After 18 months, 75 babies in the AZT group and 47 in the nevirapine group were HIV positive.

'Safe and effective'

Dr Brooks Jackson, director of pathology at Johns Hopkins, said: "If widely implemented, this has the potential to prevent several hundred thousand new infections every year.

"This regimen is extremely safe, simple and inexpensive - but access to HIV testing and counselling remains a huge obstacle."

He said he hoped the extra millions promised for Aids prevention by President Bush could be harnessed to promote the nevirapine programme.

However, other experts are warning that single-dose treatments such as nevirapine should not be used in a widespread programme, in case it increases the risk of resistance to similar anti-HIV drugs.