A person is said to have hearing loss if they are not able to hear as well as someone with normal hearing, meaning hearing thresholds of 20 dB or better in both ears. It can be mild, moderate, moderately severe, severe or profound, and can affect one or both ears.
The term, “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 devices, as well as captioning. Cochlear implants also benefit people who have more significant hearing loss. People who are diagnosed as “deaf” mostly have profound hearing loss, which implies very little or no hearing. Deaf people often use sign language for communication.
Major causes of hearing loss include congenital or early onset childhood hearing loss, chronic middle ear infections, noise-induced hearing loss, age-related hearing loss, and ototoxic drugs that damage the inner ear.
How do loud sounds cause hearing loss?
Sensory cells within our ears help us to hear. Exposure to loud sounds for any length of time causes fatigue of these sensory cells. The result is temporary hearing loss or tinnitus. A person enjoying a loud concert, for example, may afterwards experience muffled hearing or a ringing or buzzing in their ears. This often improves as the sensory
cells recover. However, with regular exposure, particularly to loud or prolonged noise, damage of the sensory cells and other structures can be permanent, resulting in irreversible noise-induced hearing loss, tinnitus, or both.
Other causes of noise-induced hearing loss include loud bursts of sound, such as gunshots, explosions, or fireworks, or continuous exposure to loud sounds over time, such as working with loud machinery.
Recreational activities that pose similar risks include riding motorcycles, shooting or hunting, listening to music at high volume when using earbuds or headphones, and regular or prolonged visits to loud entertainment venues such as music concerts or nightclubs.
Noise-induced hearing loss can be immediate (such as when exposed to a sudden burst of loud sound); however, more often the loss is gradual, permanent, and frequently goes unnoticed or ignored until the effects become more obvious. Sounds may become distorted or muffled; a person may find it difficult to understand other people when they speak, especially in places where there is background noise such as in restaurants; or they may have to turn up the volume when watching the television.
Impact of Hearing Loss:
When unaddressed, hearing loss impacts many aspects of life at individual level:
Communication and speech
Education and Employment: In developing countries, children with hearing loss and deafness often do not receive schooling. Adults with hearing loss also have a much higher unemployment rate. Among those who are employed, a higher percentage of people with hearing loss are in the lower grades of employment compared with the general workforce.
Social isolation, loneliness and stigma
Impact on society and economy
WHO estimates that unaddressed hearing loss poses an annual global cost of US$ 980 billion. This includes health sector costs (excluding the cost of hearing devices), costs of educational support, loss of productivity, and societal costs. 57% of these costs are attributed to low- and middle-income countries.
Prevention of hearing loss is essential throughout the life course – from prenatal and perinatal periods to older age. In children, nearly 60% of hearing loss is due to avoidable causes that can be prevented through implementation of public health measures. Likewise, in adults, most common causes of hearing loss, such as exposure to loud sounds and ototoxic medicines, are preventable.
Effective strategies for reducing hearing loss at different stages of the life course include:
- good maternal and childcare practices;
- genetic counselling;
- identification and management of common ear conditions;
- occupational hearing conservation programmes for noise and chemical exposure;
- safe listening strategies for the reduction of exposure to loud sounds in recreational settings; and
- rational use of medicines to prevent ototoxic hearing loss.
On World Hearing Day 2022, WHO will focus on the importance of safe listening as a means of maintaining good hearing across the life course.
The World Hearing Day 2022 with the theme “To hear for life, listen with care” will focus on the importance and means of hearing loss prevention through safe listening, with the following key messages:
- It is possible to have good hearing across the life course through ear and hearing care
- Many common causes of hearing loss can be prevented, including hearing loss caused by exposure to loud sounds
- ‘Safe listening’ can mitigate the risk of hearing loss associated with recreational sound exposure
- WHO calls upon governments, industry partners and civil society to raise awareness for and implement evidence-based standards that promote safe listening
Link to WHO World Hearing Day page:
Link to WHO fact sheet on deafness and hearing loss:
Link to WHO questions and answers page on safe listening: