South Africa announced ambitious new plans Tuesday for earlier and expanded treatment for HIV-positive babies and pregnant women, a change that could save hundreds of thousands of lives in the nation hardest hit by the virus that causes AIDS.

President Jacob Zuma — once ridiculed for saying a shower could prevent AIDS — was cheered as he outlined the measures on World AIDS Day. The new policy marks a dramatic shift from former President Thabo Mbeki, whose health minister distrusted drugs developed to keep AIDS patients alive and instead promoted garlic and beet treatments. Those policies led to more than 300,000 premature deaths, a Harvard study concluded.

The changes are in line with new guidelines issued a day earlier by the World Health Organization that call for HIV-infected pregnant women to be given drugs earlier and while breast-feeding. By treating all HIV-infected babies, survival rates should also improve for the youngest citizens in South Africa, one of only 12 countries where child mortality has worsened since 1990, in part due to AIDS.

Zuma compared the fight against HIV, which infects one in 10 South Africans, to the decades-long struggle his party led against the apartheid government, which ended in 1994 with the election of Nelson Mandela in the country's first multiracial vote.

"At another moment in our history, in another context, the liberation movement observed that the time comes in the life of any nation when there remain only two choices: submit or fight," Zuma said. "That time has now come in our struggle to overcome AIDS. Let us declare now, as we declared then, that we shall not submit."

Zuma was greeted with a standing ovation when he entered a Pretoria exhibition hall filled with several thousand people.

In some ways, Zuma is an unlikely AIDS hero. As his Zulu tradition allows, he has three wives — experts say having multiple, concurrent partners heightens the risk of AIDS. And in 2006, while being tried on charges of raping an HIV-positive family friend, he testified he took a shower after extramarital sex to lower the risk of AIDS. He was acquitted of rape.

The one-time chairman of the country's national AIDS council may never live down the shower comment. But Zuma has won praise for appointing Dr. Aaron Motsoaledi as his health minister. AIDS activists say Motsoaledi trusts science and is willing to learn from past mistakes.

South Africa, a nation of about 50 million, has an estimated 5.7 million people infected with HIV, more than any other country.

UNAIDS executive director Michel Sidibe, who took the podium shortly before Zuma, told the president: "What you do from this day forward will write, or rewrite, the story of AIDS across Africa."

Zuma said in his speech broadcast across South Africa on state radio and television that the policy changes would take effect in April. They include treatment for all children under 1 year old, regardless of their level of CD4 cells, a measure of immune system health.

Patients with both tuberculosis and HIV will get treatment if their CD4 count is 350 or less, compared to 200 now, which means treatment would start earlier. Pregnant women who are HIV-positive also would start treatment earlier. That is in line with the new WHO recommendations that doctors start HIV patients on drugs when their level of CD4 cells is about 350.

The expanded treatment was expected to be free, as it is now, although Zuma did not confirm that. He said all health institutions, not just specialist centers, would provide counseling, testing and treatment.

He also called on South Africans to get tested for HIV. But, contrary to speculation in recent days, he did not take an HIV test Tuesday.

"I have taken HIV tests before and I know my status," he said. "I will do another test soon as part of this new campaign. I urge you to start planning for your own tests."

Kurt Firnhaber, who runs Right to Care, one of the largest private providers of AIDS treatment, counseling and testing in South Africa, said Zuma outlined "steps that aren't rhetoric — if they're implemented."

He said the burden would now be on the government and foreign donors to find the money to meet Zuma's ambitious goals.

On Tuesday, in response to a plea from Zuma, the United States announced it was giving South Africa $120 million over the next two years for AIDS treatment drugs. That is in addition to $560 million the U.S. has already pledged to give South Africa in 2010 for fighting AIDS.

Mark Heywood, executive member of the Treatment Action Campaign, an independent group that has challenged the South African government on AIDS, said the Zuma speech marked a departure in thinking that would have a global impact. Heywood shared the stage with Zuma on Tuesday.

"It was a very good speech in all its aspects — the empathy he showed, what he said about prevention and the need to test for HIV was all very positive," Heywood said.

Zuma's government had earlier set a target of getting 80 percent of those who need AIDS drugs on them by 2011.

Setjhaba Ranthako brought his 4-year-old daughter Tshegofatso to hear Zuma's speech, saying education should start early.

"I've seen in President Zuma a person who's willing to listen, and say, `Here I am, come with your views, and let's turn your views into an effective campaign to combat the spread" of AIDS, said Ranthako, who works with a group that raises awareness about AIDS among men.

The crowd rose to their feet when Zuma finished his speech. Then he danced along with a choir that sang: "Zuma, you are blessed."