South Africa has earned praise for its success in reducing HIV infections and for making antiretroviral treatment widely available.
The UN global report on HIV/Aids, released yesterday, highlights international progress in slowing the spread of the epidemic.
The executive director of UNAids, Michel Sidibé, praised South Africa for "increasing its HIV treatment by 75% in the last two years".
About 1.7million of the 5.1million HIV-positive South Africans now have access to ARVs.
The report noted that there were 100000 fewer deaths from HIV in South Africa last year compared to 2010, and the infection rate had fallen by 50000 between 2009 and last year.
The reduction is in line with a global trend.
The report reads: "Countries are making historic gains towards ending the Aids epidemic - 70000 fewer HIV infections across the world in 2011 than in 2001."
The report noted the reduction in mother-to-child HIV transmission worldwide. South Africa has cut the transmission rate by 40% in the past two years.
Sidibé said: "I am excited that far fewer babies are being born with HIV. We are moving from despair to hope."
Despite the progress, more than 2.5million people worldwide were infected with the virus last year.
Women, especially in sub-Saharan Africa, were the most vulnerable, accounting for 58% of all new infections in the region.
But women were more likely to gain access to ARV treatment because it would be prescribed when they attended ante-natal clinics.
The report said that many people did not take their medication as they should. This was a worldwide problem that would have to be dealt with.
Health Minister Aaron Motsoaledi's spokesman, Joe Maila, said yesterday: "We are pleased that we are making progress but we cannot sit on our laurels. We need to make sure that everyone takes prevention seriously.
"We need to prevent infections. Every citizen needs to have an HIV test."
The report stated that "of the 34million people living with HIV, about half do not know their HIV status.
If more people knew their status, they could come forward for the HIV services they need."
The report shows that last year:
5.1 million of the world's 34million HIV-positive people live in South Africa;
1.7 million people died from Aids-related sicknesses; and
2.5 million new infections were recorded globally.