The United Nations yesterday cut its estimate of the number of people infected with the Aids virus by more than six million.

The UN Aids agency revised its estimate of HIV cases around the globe from 39.5 million to 33.2 million, including 2.5 million children.

The Geneva-based organisation said the 16 per cent downward revision was due to better data, particularly in India, rather than any change in the spread of the disease.

Some critics have accused the UN of inflating its Aids numbers and said the revision was overdue. “They’ve finally got caught with their pants down,” said Jim Chin, a former WHO official and author of The

Aids Pandemic: The Collision of Epidemiology with Political Correctness, who is a professor at the University of California at Berkeley.

But Kevin De Cock, head of HIV/Aids at the World Health Organisation, rejected any suggestion that the UN had boosted the numbers to increase Aids funding.

The UN report noted that the rate of new infections had peaked in the late 1990s at more than three million a year. But the survey found that there were still 2.5 million new infections in 2007 and approximately 2.1 million deaths from Aids.

That translates into 6,800 people becoming infected with the HIV virus every day, and more than 5,700 people dying from the disease.

The UN also changed its estimate on how long it takes to die of Aids if not treated from 9 years to 11 years.

About half of the downward revision in the global total of HIV cases was attributable to India, where the estimate number of those infected was more than halved from 5.7 million to 2.5 million. Most infected Indians live in the four southern states of Andhra Pradesh, Karnataka, Maharashtra and Tamil Nadu.

Also cut significantly were estimates for the sub-Saharan African countries of Angola, Kenya, Mozambique, Nigeria, and Zimbabwe.

UN experts attributed the change to better data gathered from household surveys rather from than blood samples taken at health clinics.

Although expensive, household surveys reach further into remote rural areas and represent the general population better. Samples at clinics tend to overrepresent pregnant women, who become infected at a disproportionately high rate.

But Karen Stanecki, a UN Aids epidemiologist, noted that household surveys were not the “gold standard”, because they might miss high-risk groups such as prostitutes, homosexuals and intravenous drug users.

The Aids crisis remains worst in sub-Saharan Africa, which had 68 per cent of new worldwide infections this year and 76 per cent of Aids deaths.

Outside Africa, the epidemic is largely concentrated in vulnerable groups such as men who have sex with men, sex workers and their partners, and drug users who inject.

The Caribbean is the second-worst-hit region in per capita terms, with 1 per cent of adults — or 230,000 people — carrying the virus. Haiti and the Dominican Republic account for two thirds of the total.

Britain has one of the largest HIV/Aids epidemics in Europe, alongside Spain, Italy and France.

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