India is one of the largest and most populated countries in the world, with over one billion inhabitants. Of this number, it's estimated that around 2.4 million people are currently living with HIV.
HIV emerged later in India than it did in many other countries. Infection rates soared throughout the 1990s, and today the epidemic affects all sectors of Indian society, not just the groups – such as sex workers and truck drivers – with which it was originally associated.
In a country where poverty, illiteracy and poor health are rife, the spread of HIV presents a daunting challenge.