India's health ministry is to appoint private consultants to determine how many people in the country are infected with the Aids virus.
A new report says more women are likely to be infected
Health Minister Anbumani Ramadoss said a number of firms, including international consultants McKinsey, had been short-listed.
India says more than five million of its citizens are infected with the HIV virus, second only to South Africa.
But activists say the number of Indians affected by HIV/Aids is much higher.
Mr Ramadoss said Tata Consultancy and the Indian Institute of Management had been shortlisted along with McInsey and a decision would be made in a month.
"We are very much concerned. We want to check this [HIV/Aids] before it becomes a burden," he told journalists in the southern city of Madras.
In July, the government-run National Aids Control Organisation (Naco) said India had 5.1 million infections, second only to South Africa which has 5.3 million people living with HIV or Aids.
But Naco recorded 520,000 new cases in India in 2003 - a drop from the previous year - and said it meant the government's Aids campaign was working.
But Indian and international groups working to prevent HIV/Aids were swift have questioned the figures.
Last week, Richard Feacham, executive director of the Global Fund to Fight Aids, Tuberculosis and Malaria, said HIV/Aids was a "ticking time-bomb" for India and said the country's surveillance network was inadequate.
Two years ago, the United States National Intelligence Council estimated there were five million to eight million HIV-infected people in India, a number it said could swell to 20-25 million by 2010.
And last year, a report from the Global HIV Prevention Working Group warned that China and India are standing "on the brink of widespread epidemics", as HIV spreads from groups at high risk to the broader population.
Women at risk
But Health Minister Ramadoss says there is no need to panic as only 0.5% of Indians have been infected, compared to 2.1% in Thailand and 2.3% in South Africa.
Half of India's new HIV infections occur in the 10-25 age group but only 59% of adolescents in the country are familiar with condoms, a government report released over the weekend said.
The report also said the level of HIV infection among women is likely to go up, with increasing numbers of married women being infected by their husbands.