Yet, data illustrating the size of the problem is hard to come by because of the lack of resources in the health sector in third world countries and the nature of hearing loss, which is often viewed as a hidden disability.
In 1995 the UN World Health Organization, WHO, estimated that more than 25 million people in Southeast Asia suffer from "disabling" hearing loss.
- 20 million Chinese suffer from hearing loss, according to data released in 2008 by the China Disabled Persons' Federation (CDPF). 20 million is the number of recorded instances by CDPF. The actual number of hearing impaired Chinese is likely to much higher. According to CDPF, 43 percent of hearing impaired Chinese cannot afford hearing aids.
- In Thailand, data indicates that approximately 13.5 percent of the population suffer from hearing loss.
- In rural Pakistan one child in 12 is suffering from hearing loss.
In many less developed areas of countries such as Malaysia, India, Pakistan and Saudi Arabia the knowledge and awareness of hearing loss is low. Surveys from India, Thailand and Pakistan indicate that hearing loss among children is more wide-spread in rural areas because of the prevalence of dangerous infectious diseases.
In China, Pakistan and Saudi Arabia, some of the hearing loss may be caused by genetic defects related to marriages between close relatives.