AIDS activists and human rights advocates are lauding a decision by the South African constitutional court. The unanimous decision forces the South African government to provide the drug, Nevarapine, to pregnant women to prevent them from transmitting HIV to their unborn children.

Right now the drug is only available at so-called pilot sites.

It's believed the court's decision could cut in half the number of babies born with AIDS in South Africa

Spontaneous applause broke as the court decision was announced at a special meeting of AIDS activists and human rights advocates in Barcelona. The decision comes just two days before the opening of the 14th International AIDS conference which is being held in the Spanish city.

Mark Heywood is heads the AIDSLAW project in South Africa. His organization was among those that took on the case to pressure the government to provide treatment to prevent the spread of HIV from mother to child.

He spoke with emotion about one woman who was instrumental in taking this case to the courts. "My thoughts were of one person in particular. A young mother called Sara Laclele who died in April of this year and her affidavit, I think, was a critical affidavit because it explained how she'd known about Nevarapine. She, in fact, got the medicine but went into premature labor and was taken to hospital without the medicine and her little boy has HIV.

The decision will force the South African government to provide Nevarapine to all pregnant women. The drug is already being donated free of charge by its manufacturer.

Justice Edwin Cameron of South Africa's high court of appeal is a well-known AIDS activist. He could not suppress his delight when he heard the news in Barcelona.

"I was overjoyed. I'm also, apart from being a judge, I'm a person living with AIDS. I know what it did to my body four and a half years ago, I don't want a single child in the world to have a broken disintegrated immune system. So I was overjoyed," he said.

Right now at least 70,000 babies are born with AIDS in South Africa every year. Cameron says the decision could prevent more than half of those infections.

The decision has wider implications, according to Richard Elliott, a lawyer with the Canadian HIV/AIDS legal Network. He says it compels governments to look at the provision of health care as a legally enforceable right.

"It is possible to go to court and say, 'I have a right to health. That means you have to do certain things as a government and if you don't I can go to court and hold the government accountable.' So that could make a difference to people everywhere."

Elliott says the decision could even have implications in Canada, where policy makers have long maintained that that such rights as the right to health care, can't be enforced by the courts.