Hearing thresholds of 25 dB or better in both ears is referred to as normal hearing. A person who is not able to hear as well as someone with normal hearing is said to have hearing loss. Hearing loss may be mild, moderate, severe or profound in degree. It can affect one or both ears and leads to difficulty in hearing conversational speech or loud sounds.
It is estimated that there are currently around 466 million people or 5.9% of the world’s population is affected with disabling hearing loss (WHO 2018). On an average, 1 to 3 in every 1,000 children in the world are born with permanent hearing loss each year. In India alone, more than 25 million children are born every year leading to addition of more than 25000 children with disabling hearing loss into the society. WHO (2018) reported that approximately 7% people in South Asia, including India, are affected with hearing loss. As per last census (2011), India’s population was 1.2 billion which accounts for 17% of the world’s total population. It can be estimated that in 2011 alone 84 million people were affected with disabling hearing loss and with rising population this figure could be as high as 95 million today.