India\'s Prime Minister Manmohan Singh on Monday hailed the country\'s success in slashing new HIV/AIDS infections by half in the past decade, but warned against complacency. \"Our HIV/AIDS programme can justifiably claim a measure of success,\" he told a conference in New Delhi discussing means to combat the disease. But he added that new Ministry of Health figures estimating that 2.4 million Indians are still living with HIV means \"there should be no room for complacency\". \"With the introduction of antiretroviral treatment, HIV has become a chronic but manageable health condition,\" Singh said. While Singh was praising government efforts to combat the virus, around 100 people living with HIV protested outside the ministry of health saying efforts were insufficient. Despite the significant drop in fresh cases, India still has the highest number of people living with HIV after South Africa and Nigeria. So-called \"first-line\" antiretroviral therapy (ART) -- a cocktail of drugs to slow the effects of the virus on the body\'s immune system -- has been widely available and free of charge in India\'s public health system since 2004. More expensive \"second-line\" ART is also free, although access to it is limited to just a few centres across the country. \"India\'s testing and treatment for HIV/AIDS have increased their reach,\" Singh said. Now, Indian health workers are focusing on prevention of transmission from infected pregnant women to their newborn children, making it a \"priority area,\" Singh said. India\'s AIDS control programme has reduced new HIV/AIDS infections by 50 percent in the last 10 years and mortality rates amongst those infected with HIV have also fallen, Singh noted. The health ministry said the number of new HIV infections in India has fallen to to 120,000 annually from 270,000 reported in 2000. Indian pharmaceutical companies have helped to drive down the cost of life-saving generic drugs to treat people with HIV in India and other developing countries. Singh said one of India\'s key strategies has been to scale up preventive education campaigns among high-risk groups such as sex workers. Other high risk groups include men having sex with men, India\'s health minister Ghulam Nabi Azad said. \"We can track female sex workers but it is almost impossible to identify men having sex with men. We need to take the message to them to further stabilise the epidemic,\" Azad said separately at the conference. Unprotected sex, particularly between sex workers, their clients and partners, is the main factor behind the spread of the disease, UNAIDS says. Contaminated needles also play a key role in spreading the virus in India\'s northeastern regions, the UN agency says. Singh said there should be no discrimination in India against people living with HIV, condemning frequent denial of school admission to children with the virus. \"We must see that there is no social ostracisation,\" he said. He also urged the global community not to slacken in its fight against what he called one of the \"biggest health challenges confronting humanity.\"