According to a central health ministry report, Delhi reported 743 new AIDS cases between January and June 2007 while 97 people succumbed to the disease during the same period.
The ministry said there had been only 64 AIDS patients in 1994, but now the figure has crossed 5,000.
'There could be two reasons behind the increasing number of AIDS cases in Delhi - first the increasing number of floating population and second the initiation of the anti-retroviral treatment (ART) programme,' said a ministry official.
'In the last three years the situation has become alarming. While the number of AIDS patients was just 949 in 2004, it jumped to 2,414 by December 2005,' said a ministry official.
'2006 was the worst year in Delhi, with the city reporting 1,925 cases last year. At least 80 people also died of AIDS last year which is almost double the number of deaths in 2005,' the official told IANS.
The report revealed that since 1993 Delhi has recorded 460 deaths from the disease.
Currently, India is home to over 2.5 million HIV/AIDS patients, according to new estimates published jointly by the World Health Organisation (WHO), UNAIDS and the National AIDS Control Society (NACO).
The earlier estimate was 5.2 million.
Mahesh Ganesan, a doctor working with the non-profit AIDS Healthcare Foundation (AHF), said: 'Apart from the migrating population and free treatment, what is more important is the vulnerability factor'.
'It's a myth that a large population in Delhi is aware of AIDS. Industrial workers and youth remain the main vulnerable sections. Higher prevalence of pre-marital sex - sometimes in adolescence - also contribute to the numbers,' he added.
'Seen in a nationwide perspective, Delhi is not a high prevalence state. Yet it is in a transition phase. People, government and voluntary health workers, therefore, must be cautious to check this growth.'
Health ministry officials said the recently launched National AIDS Control Programme-III has set a target of halting and reversing the spread of the disease over the next five years.
'So far as Delhi is concerned, our state AIDS Control Society has drawn up a major mission to create awareness,'said an official in the state health ministry.
'Railway stations, the Metro, bus terminals and major shopping areas are the focus points. And the medium includes FM radio, the usual print advertisements, posters and banners by the thousands and hundreds of hoardings and panels.'