Estimates of the number of people living with HIV in South Africa range from 5.3 million to more than 6 million -- more than in any other country.

A national household survey commissioned by The Nelson Mandela Foundation, which included conducting HIV tests on respondents, found prevalence among 15- to 49-year-olds was 16.2 percent in 2005, only a slight increase from the 15.6 percent recorded in 2002.

But investigators from the Human Sciences Research Council of South Africa said increasing mortality rates influenced the figures and the rate of new infections remained high.

An alarming 66 percent of respondents did not think they were at risk of infection -- including just over half of those who tested positive for HIV --according to the findings released on the eve of World AIDS Day.

"That means we have more than 2 million people walking the streets of South Africa who are HIV positive and think they probably are not," said Olive Shisana, lead researcher and head of council. They in turn may be unaware of their risk of infecting others.

Living with HIV

Estimates of the number of people living with HIV in South Africa range from 5.3 million to more than 6 million -- more than in any other country.

The virus has cut a swathe through South African society. Some 2.5 million children have lost one or both parents to AIDS and other causes.

HIV/AIDS is also reducing productivity and increasing absenteeism in the key mining, manufacturing, transport and financial services sectors, according to a separate study by the University of Stellenbosch's Bureau for Economic Research. Mining companies estimate the virus is adding a couple of dollars (euros) per ounce to the gold price, said Brad Mears, chief executive of the South African Business Coalition on HIV/AIDS.

Human Sciences Research Council researchers found the risk to women is higher than men, with women in the 15-24 age group up to four times more likely to be infected than their male counterparts. HIV strikes hardest at those in their reproductive prime, but men and women over 50 are not immune, the survey found.

Recent Infections

New tests developed by the US Centers for Disease Control permitted for the first time the identification of recent infections. Researchers expressed concern about the results: a total of 181 samples -- 2.7 percent -- were infected with HIV less than 180 days before the test.

They included 11 children aged 2-14, representing 0.9 percent incidence, which Shisana called "way too high."

Most respondents expressed positive attitudes toward people living with HIV in a country where stigma still runs high. More than 90 percent said they were willing to care for an infected relative, and just under 80 percent said infected children should not be separated from their peers.

But researches noted partner turnover remains high, the age of sexual debut is getting lower and too many people -- especially women -- are not using condoms.

Slow Response

It was the second time The Nelson Mandela Foundation commissioned the survey on HIV prevalence, incidence, behavior and communication among South Africans 2 years and older. More than 23,000 people took part, of whom 15,851 agreed to be tested.

President Thabo Mbeki's government has drawn criticism for its slow response and mixed messages about the crisis. Mbeki famously questioned the link between HIV and AIDS, and his government only started providing life-prolonging treatment in 2004.

Mandela has used his status as an anti-apartheid icon to call attention to the disease since he retired as South Africa's first black president in 1999.