By Justin Pearce
BBC News website, Johannesburg
The revelation that former South African Deputy President Jacob Zuma had sex without a condom has prompted outrage from Aids educators and activists.
Some say Mr Zuma's generation is less willing to change their behaviour
Mr Zuma, 63, is on trial for rape. He denies the charge, but admits having had sex with the woman accusing him.
The complainant in the case cannot be identified, but is known to be HIV positive and an Aids activist, as well as being a family friend.
South Africa has more people - 5m - with HIV than any other country.
The government has frequently been accused of not taking Aids seriously.
During questioning by his defence counsel, Mr Zuma, former head of the National Aids Council, said that according to his understanding, it was difficult for a man to contract HIV through sex with a woman.
"I had knowledge that... chances were very slim you could get the disease."
Aids educators now fear that while female-to-male HIV transmission is indeed less common than male-to-female transmission, Mr Zuma's explanation could be interpreted as meaning men are not at risk.
"Statements like that can throw years of hard work down the drain," says Vicci Tallis of the Gender Aids Forum - echoing the dismay expressed by other Aids activists, whose unease has been compounded by Mr Zuma's previous high-profile role in government.
The alleged rape victim has not been named outside court
As deputy president, he headed both the National Aids Council - a government-led co-ordinating body - and the Moral Regeneration Campaign, a portfolio assigned to him by President Thabo Mbeki.
Mr Zuma said he regularly used condoms and denied that his actions had undermined the battle against Aids.
Sue Goldstein of Soul City, an HIV education and information group, says Mr Zuma's statements in court "bring the issues to the fore, but also show what we're battling against".
'Lack of leadership'
She says that while many South Africans remain in denial about Aids, equally worrying is "another group saying they can't control their sexuality, but believe that as men they are less at risk."
She points to "lack of leadership" as one of the problems hindering the struggle against HIV transmission in South Africa, and says it "boggles the mind" that the former leader of the Moral Regeneration Campaign could act in the manner that he admitted to in court.
The fact that Mr Zuma invoked traditional culture as an excuse for not using a condom is a matter of concern, says Dumisani Rabombo from the Men as Partners Programme of the organisation Engender.
"People may think there are African ways of having penetrative sex but with minimal risk of HIV. That doesn't exist," he says.
Mr Rabombo adds that in the experience of his work, older people are more likely than younger people to have faith in unreliable and dangerous traditional beliefs surrounding Aids.
"But you can't guarantee that some young people - especially those who are pro-Zuma - might not think themselves safe," he says.