CAPE TOWN, South Africa (AP) -- South Africa's new health minister broke dramatically on Monday from a decade of discredited government policies on AIDS, declaring that the disease was unquestionably caused by HIV and must be treated with conventional medicine.

Health Minister Barbara Hogan's pronouncement marked the official end to 10 years of denying a link between HIV and AIDS by former President Thabo Mbeki and his health minister Manto Tshabalala-Msimang.

Activists also accused Tshabalala-Msimang of spreading confusion about AIDS by saying she did not trust antiretroviral medicines and preferred nutritional remedies such as garlic, beetroot, lemon, olive oil and the African potato.

"We know that HIV causes AIDS," Hogan said in a speech Monday. It was her highest-profile public appearance since she became health minister two weeks ago after Mbeki was turned out of office by his party.

"I want to emphasize that we will scale up mother-to-child prevention programs," she said, referring to treatments using anti-retroviral medicine to keep HIV-positive pregnant woman from passing on the disease.

Hogan said government policies over the past 10 years had failed and said South Africa needed to do much more to improve access to anti-AIDS medicines.

She vowed to step up the battle against AIDS, which now accounts for half of all public hospital admissions.

She was applauded and praised at the opening ceremony of an international AIDS vaccine conference by international scientists and public health officials who were frequently spurned by former health minister.

"A breath of fresh air," said Alan Bernstein, executive director of the Global HIV Vaccine Enterprise.

Tshabalala-Msimang's views earned her the nicknames "Dr. Garlic" and "Dr. Beetroot" and made her a favorite target for cartoonists.

South Africa now has the world's highest number of people with HIV, counting some 5.4 million people as infected with the virus that causes AIDS, activists say.

Malegapuru Makgoba, vice chancellor and principal of the University of KwaZulu-Natal, said that for the first time in years, South African academics are free to "state that HIV causes AIDS without getting threats."

"It is a liberating experience," Makgoba said at the conference, winning applause. "You don't know how long we suffered in bondage."

Hogan told the conference that countries such as South Africa -- where life expectancy has fallen to 52 years -- desperately need scientists to come up with a vaccine against HIV.

"I'm told that it could take anything from 15 years to a century to get an effective vaccine and that it's at least 25 years since the scientific community started looking for an HIV vaccine. I challenge you to look harder and faster," Hogan said.

More than 6,500 new HIV infections occur daily worldwide, and about 1,000 of these in South Africa.