Deafness is the third most common disability in the world. In this article, Ability Central will address the following:

• How common are hearing loss and deafness?
• What are the types of hearing loss?
• When can hearing loss and deafness occur?
• What causes hearing loss?
• Can hearing loss be reversed?
• When is hearing loss considered deafness?
• What is the difference between Deaf and deaf? 
• What is late-deafness?
• Where can I get more information?

How common are hearing loss and deafness?

About 2 to 3 out of every 1,000 children in the United States are born with detectable hearing loss in one or both ears. And more than 90 percent of Deaf children are born to hearing parents.

Hearing loss is different from deafness as it can be a natural part of the aging process. For some, hearing loss can be so profound that it is disabling. 

About 11.5 million Americans have a hearing impairment, ranging from difficulty in hearing conversation to total hearing loss. That's about 3.5% of the population. According to the National Institute of Deafness and Other Communication Disorders (NIH):

• about 2 percent of adults aged 45 to 54
• 8.5 percent of adults 55 to 64
• 25 percent of those aged 65 to 74, and 
• 50 percent of those who are 75 and older have disabling hearing loss. 

What are the types of hearing loss?

There are three types of hearing loss.

• Conductive (involves outer or middle ear)
• Sensorineural (involves inner ear)
• Mixed (combination of the two)

Each has different ways in which they are tested and treated by doctors.

When is hearing loss considered deafness?

The World Health Organization (WHO) breaks hearing loss and deafness into three categories.

• A person who cannot hear as well as someone with normal hearing – hearing thresholds of 20 dB or better in both ears – is said to have hearing loss. The Ability Central Portal has a library of articles on hearing loss to help you understand the diagnosis and early signs.
• Hard of hearing refers to people with hearing loss ranging from mild to severe. People who are hard of hearing usually communicate through spoken language and can benefit from hearing aids, cochlear implants, and other assistive devices and captioning. 
• People who are Deaf usually have profound hearing loss, which implies very little or no hearing. Deaf people often use sign language for communication, and are likely to associate culturally with deafness, often regarding it not as a disability but as a facet of their identity. 

What is the difference between “Deaf” and “deaf”?

People who are “Deaf” with a capital “D” identify as culturally Deaf and consider themselves members of the Deaf community. They do not view deafness as a disability and may prefer not to be labeled as hard of hearing. They view deafness as an integral aspect of their identity as a complete individual. Signed language tends to be the primary language and source of communication for people who are Deaf.

The lowercase “deaf” usage is most commonly associated with a medical diagnosis of an audiological impairment, where deafness is seen as a disability. People who are deaf may use the hard of hearing label. Generally, someone who is deaf with a lowercase “d” does not identify as a member of the “capital D” Deaf community, and may use various methods of communication, including speaking, lip-reading, and assistive technologies like hearing aids or cochlear implants.

There is no single way to identify oneself within these classifications. The decision may be influenced by factors such as the degree to which a person can hear, their relationship with the Deaf and hard-of-hearing communities, or even the age when the hearing loss happened. If you are ever unsure whether someone uses “Deaf” or “deaf,” ask them which they prefer. 

When can hearing loss and deafness occur?

The World Health Organization (WHO) defines the critical periods of susceptibility for hearing loss as follows:

• Prenatal period, when genetic factors and intrauterine infections can lead to hearing loss.
• The perinatal period where hearing loss and deafness may occur from a lack of oxygen at the time of birth, severe jaundice, low-birth weight, or other perinatal morbidities and their management.
• Childhood and adolescence, where hearing loss and deafness may occur from chronic ear infections, a collection of fluid in the ear, or an illness.
• In adulthood and older age, hearing loss and deafness may result from chronic diseases, smoking, otosclerosis, age-related sensorineural degeneration, or sudden sensorineural hearing loss.

What causes hearing loss?

Aging and chronic exposure to loud noises both contribute to hearing loss. Other factors, such as excessive earwax, can temporarily reduce how well your ears conduct sounds.

Can hearing loss be reversed?

Hearing loss cannot be reversed; however, a doctor or hearing specialist can take steps to improve what you hear.

What is late-deafness?

Late-deafness refers to people who are hard of hearing or Deaf or who have lost some or all of their hearing after acquiring the ability to speak. Late-deaf people may have suddenly or gradually lost their hearing due to genetics, accidents, illnesses, medications, surgery, noise, or unknown reasons. They cannot understand speech without visual aids such as reading, text reading, captioning, sign language, or gestures.

Where can I get more information on deafness?

For more information on deafness and hearing loss, see Ability Central’s complete library of resources, including: 

• Deafness, Types of Hearing Loss, and What Causes Each
• Understanding a Hearing Loss or Deafness Diagnosis and Your Next Steps
• Long-term Support and Planning for People Who Are Deaf