For an AIDS-scary world, there is some good news. AIDS may have been one of the biggest epidemics, but scientists now believe that the size and the course of the disease have been grossly over-estimated over a decade.
In what could be a stunning revelation, the United Nations top AIDS scientists will soon acknowledge the 'mistakes', especially in sub-Saharan Africa, say media reports.
Reports say new studies have even shown that United Nations has cut its estimate of HIV cases in India by more than half.
The revisions amount to at least a partial acknowledgment of criticisms long levelled by researchers who disputed the UN version and reports about "an ever-expanding global epidemic", reports said.
The new estimate put the number of annual new HIV infections at 2.5 million, a cut of more than 40 percent from last year's estimate, reports said quoting the UN statement.
Total number of people infected worldwide with HIV -- estimated a year ago at nearly 40 million and rising -- now will be reported as 33 million.
Critics, the reports said, also said that UN officials overstated the extent of the epidemic to help gather political and financial support to combat AIDS.
"There was a tendency toward alarmism, and that fit perhaps a certain fund-raising agenda," said Helen Epstein, author of "The Invisible Cure: Africa, the West, and the Fight Against AIDS'
"I hope the new numbers will help refocus the response in a more pragmatic way."
Annemarie Hou, spokeswoman for the UN AIDS agency, speaking from Geneva declined to comment on the grounds that the report had not been released publicly.
In documents obtained by The Washington Post, UN officials say the revisions stemmed mainly from better measurements rather than fundamental shifts in the epidemic. They also say they are continually seeking to improve their tracking of AIDS with the latest available tools.
Many blame methodology for the overestimation. UN officials traditionally based their national HIV estimates on infection rates among pregnant women receiving prenatal care. As a group, such women were younger, more urban, wealthier and likely to be more sexually active than populations as a whole, according to recent studies.
The United Nations' AIDS agency, known as UNAIDS and led by Belgian scientist Peter Piot since its founding in 1995, has been a major advocate for increasing spending to combat the epidemic. Over the past decade, global spending on AIDS has grown by a factor of 30, reaching as much as $10 billion a year.
UNAIDS has drawn criticism in recent years from Epstein and others who have accused it of being politicised and not scientifically rigorous, reports said.
New studies commissioned by governments and relying on random, census-style sampling techniques found consistently lower infection rates in dozens of countries. For example, the United Nations has cut its estimate of HIV cases in India by more than half because of a study completed this year.
This week's report also includes major cuts to U.N. estimates for Nigeria. The revisions affect not just current numbers but past ones as well. A UNAIDS report from December 2002, for example, put the total number of HIV cases at 42 million. The real number at that time was 30 million, the new report says.
Researchers say that the prevalence of circumcision, which slows the spread of HIV, and regional variations in sexual behaviour are the biggest factors determining the severity of the AIDS epidemic in different countries and even within countries.