The authors of the study said the results might provide an effective and affordable new way to prevent infection of babies through breastfeeding, particularly in developing countries where there were little or no alternative to breast milk.
Social pressures in some African countries also forced some women to breastfeed even when they could afford to use the bottle.
Under the SIMBA (Stopping Infection from Mother to Child via Breastfeeding in Africa) study, the rate of infection in babies born to HIV-infected women fell sharply to one percent from 15 percent in the first six months of their lives.
The children were given either GlaxoSmithKline Plc's Epivir or Boehringer Ingelheim's Viramune while breastfeeding for up to six months. The mothers were put on a short course of GSK's AZT and Bristol-Myers Squibb's Videx while pregnant and were
counselled on how best to breastfeed.
"The combination of antiretroviral prophylaxis and counselling on breastfeeding practices in infants receiving breastfeeding from HIV-1 infected mothers is extremely effective in preventing mother to infant transmission," the authors said.
Sometimes there's no alternative
to breast milk
Short courses of antiretroviral therapy have been shown to reduce mother to child transmission of HIV after birth but the benefits are short-lived in countries where breastfeeding is the norm as the virus is passed on through breast milk.
About 2.5 million of the estimated 200 million women who become pregnant around the world each year have HIV, according to the latest UNAIDS report.
In 2001 alone, about 800,000 children were infected with the virus, almost all through mother to child transmission.
Joep Lange, President of the International Aids Society (IAS), said he would recommend the immediate implementation of the SIMBA study's findings.
"It would be best to start providing universal access to treatment for people in developing countries but in the absence of that this intervention should be recommended immediately."
But Francois Dabis, a senior AIDS researcher with France's National AIDS Research Institute, was more cautious, saying he was wary about using the strategy on a large-scale basis.
"We should view the use of these drugs in infants as a model where further studies will be conducted using the same principle rather than a very effective strategy that can immediately be used in practice," he said.