India now has more people living with HIV than any other country, a UNAids report has revealed.
Prevention strategies are having some effect in India
The report shows that India now accounts for two-thirds of HIV cases in the whole of Asia.
An estimated 5.7 million Indians were infected by the end of 2005, overtaking the 5.5 million cases estimated in South Africa.
However, While 18.8% of South African adults were living with HIV, the figure in India was 0.9%.
Estimates of total deaths in India since Aids was first identified in 1981 range from 270,000 to 680,000.
Most of the infections there were caused by unprotected heterosexual intercourse, according to UNAids.
States in southern India have traditionally been the hardest hit by the disease.
A study of prostitutes in Tamil Nadu found 50% had been infected with HIV.
However, UNAids said these regions had made progress in combating the spread of infection.
In contrast, little or no progress had been made in cutting infection rates in the north of the country, where injecting drug use is thought to be the main driver of infection.
The UN agency estimates that only 7% of Indians who needed antiretroviral drug therapy actually received it last year.
In addition, only 1.6% of pregnant women who needed treatment to prevent mother-to-child HIV transmission were receiving it.
UNAids also sounded a warning about neighbouring Pakistan, where around 85,000 people were estimated to be infected with HIV by the end of 2005.
It said the country would have to improve its prevention efforts if it is to avoid a more serious situation.
The report said that China had improved the way it monitors HIV.
Health experts had feared that failure to acknowledge the growing problem of HIV in the country would hamper efforts to combat the spread of infection.
But UNAids said it had now been able to estimate the number of cases in the country - 650,000 - with some degree of confidence.
The report estimated that 45% of injecting drug users and 25% of sex workers are now being targeted by prevention programmes in the country.
However, it estimated that just 8% of male heterosexuals were being reached by prevention programmes in 2005.
It is thought that around 25% of people with HIV in China receive antiretroviral drugs - above the Asian average of 16%.
The report also highlights significant progress in Thailand, which threatened to become an HIV black spot.
The prevalence rate in the country is now 1.6% - a third lower than in the previous decade.
It is thought prevention efforts have encouraged men to stop buying sex. Condom use has also increased.