Q: About how many deaf people
currently live in the United States and where can I find information
about the statistics in my area?
According to the National Center for Health
Statistics (2006), 37 million adults in the United States had trouble
hearing.
The following links provide more information about the number of persons
with hearing loss.
The Prevalence and Incidence of Hearing Loss in Children, American
Speech-Language-Hearing Association (ASHA):
http://www.asha.org/public/hearing/disorders/children.htm
Statistics on Hearing Loss, NIDCD:
http://www.nidcd.nih.gov/health/statistics/hearing.asp
[Return to FAQs]
Q: How common is hearing loss
in children?
Hearing loss occurs in approximately 12,000 children
each year (up to 3 of every 1,000 births). According to the National
Institute on Deafness and Other Communication Disorders (NIDCD), about
28 million people in the U.S. have some degree of reduced hearing. ,An
estimated 15 percent of children and teenagers in the United States have
a temporary or permanent hearing loss in one or both ears.
The Prevalence and Incidence of Hearing Loss in Children, American
Speech-Language-Hearing Association (ASHA):
http://www.asha.org/public/hearing/disorders/children.htm
Prevalence and Incidence of Hearing Loss in Adults:
http://www.asha.org/public/hearing/disorders/prevalence_adults.htm
Statistics on Hearing Loss, NIDCD:
http://www.nidcd.nih.gov/health/statistics/hearing.asp
[Return to FAQs]
Q: What is degree of
hearing loss?
The degree of hearing loss refers to the severity of
the loss. Someone with normal hearing can hear sounds of all different
loudness and pitch while a person with a hearing loss might be able to
hear some sounds only or might hear nothing at all. Hearing loss can
affect one ear (unilateral) or both ears (bilateral.
Sound is measured in both decibel (represent loudness) and frequency
(represent pitch). Different groups and organizations define the levels
of hearing loss differently. For instance, the organization American
Speech-Language-Hearing Association (ASHA) measures hearing loss by
using the following categories:
Average Hearing Level (in decibels, dB)
There are several categories that are typically used. Below is just one
way to measure hearing level without a hearing aid or other devices to
increase the sound. The numbers in parenthesis mark the range of hearing
loss in decibels.
-
Normal Range (-10–15 dB): A child will hear all
speech sounds.
-
Slight Hearing Loss (16-25 dB): A child will
hear vowel sounds clearly, but might miss some consonants sounds.
-
Mild Hearing Loss (26–40 dB): A child will hear
only some of the speech sounds.
-
Moderate Hearing Loss (41–55 dB): A child will
hear almost no speech sounds at a normal speaking level.
-
Moderate/Severe Hearing Loss (56–70 dB): A child
will hear no speech sounds at a normal speaking level.
-
Severe Hearing Loss (70–90 dB): A child will
hear no speech and almost no other sound.
-
Profound Hearing Loss (91+ dB): A child will
hear no speech and no other sound.
Source: American Speech-Language-Hearing
Association,
(http://www.asha.org/public/hearing/disorders/types.htm)
As the two examples above show some groups may use
slightly smaller or slightly larger numbers for each of the categories,
therefore each defines the levels of hearing loss differently. Because
the degrees of hearing loss have not been defined universally, it is
difficult to compare studies that give statistics. CDC is working to
obtain better estimates of the prevalence of hearing loss through
on-going research activities. Please check the CDC-EHDI website again,
as we will provide more statistics as they become available.
The following websites may also be useful.
Please note: not all of the information is complete and some of it
focuses on more than young children.
The Prevalence and Incidence of Hearing Loss in
Children, American Speech-Language-Hearing Association (ASHA):
http://www.asha.org/public/hearing/disorders/children.htm
Prevalence and Incidence of Hearing Loss in Adults:
http://www.asha.org/public/hearing/disorders/prevalence_adults.htm
Statistics on Hearing Loss, NIDCD:
http://www.nidcd.nih.gov/health/statistics/hearing.asp
[Return to FAQs]
Q: What is the type
and severity of hearing loss in infants throughout the United States?
Please note that some of this
information is estimated and may not be exact. Not all states
and territories were able to report this type of data. For
additional state and territorial data by year please
click here.
2006 Type and Severity Data
2005 Type and Severity Data
Summary of 2005 Type and Severity
Data (by ear)
Please note that the 2005
data about type and severity of hearing loss was collected
using a different survey than was used to collect the 2004
data.
2004 Type and Severity Data
Type and Severity for Cases of Unilateral Hearing Loss (2004)
Type and Severity for Cases of Bilateral Hearing Loss (2004)
2003 Summary
A
total of 44 states and territories reported that 2,899
infants born in year 2003 were identified with a Permanent
Childhood Hearing Loss (PCHL).
The prevalence of PCHL among
these states in 2003 = 1.09 per 1,000 infants screened
Type and Severity of PCHL
A total of 33 of these 44 states
and territories reported some data about the type and severity
of identified PCHLs.
2,003 children were identified
with a hearing loss within these 33 states and territories.
The prevalence of PCHL in these
states = 1.16 per 1,000 infants screened.
|
Severity of PCHL |
Unilateral |
Bilateral |
|
|
|
|
|
Mild
|
31.1% |
26.1% |
|
Moderate |
31.8% |
28.3% |
|
Severe |
15.3% |
16.0% |
|
Profound |
12.0% |
18.0% |
|
|
|
|
|
Unknown |
9.8% |
11.6% |
Prevalence of Unilateral and Bilateral PCHL
A total of 516 cases of unilateral hearing loss were
identified in these 33 states and territories.
-
516/1,733,762* x 1,000 = 0.30 per 1,000
A total of 1,043 cases of bilateral hearing loss were
identified in these 33 states and territories
-
1,043/1,733,762* x 1,000 =
0.60 per 1,000
1,733,762*: Number screened for hearing loss within these
33 states and territories in year 2003.
[Return to FAQs]
Q: What are common
symptoms of deaf or hard of hearing children?
-
Your child is inconsistently responding to sound
-
Language and speech development is delayed
-
Speech is unclear
-
Sound is turned up on electronic equipment (radio,
TV, cd player, etc.)
-
Your child does not follow directions
-
Your child often says "Huh?"
-
Your child does not respond when called.
If you have concerns, have your child’s hearing
tested by an audiologist.
Visit the following website to find an audiologist in your area,
http://www.asha.org/findpro/
or
American Academy of Audiology
http://webportal.audiology.org/Custom/FindAnAudiologist.asp.
For further
information, see the following sites:
Information on symptoms of hearing loss in young
children
http://www.nidcd.nih.gov/health/hearing/silence.asp
Information on symptoms of hearing loss in older
children
http://www.asha.org/public/hearing/disorders/default.htm
[Return to FAQs]
Q: What are some medical
conditions that are linked to the chance of hearing loss in infants and
young children?
About 3 in 1,000 babies are born with some
degree of hearing loss. Children can also develop hearing loss after
birth.
Approximately 50% of hearing loss in children
has a genetic cause. Genetic causes have to do with the baby’s
genes. Genes are in the cells of a person’s body and contain
instructions that tell the cells of the person’s body how to grow
and work. For example, the instructions in genes control hair and
eye color. About 30% of children with genetic hearing loss have a
“syndrome.” This means they have other conditions linked with the
hearing loss. Examples are Down Syndrome and Usher Syndrome. The
other 70% of children with genetic hearing loss have hearing loss
that is “non-syndromic.” This means there are no other conditions
linked with the hearing loss.
A non-genetic
cause can be found in about 25% of cases of hearing loss.
Non-genetic causes of hearing loss include
-
An infection that the mother might have
gotten during pregnancy. Cytomegalovirus (CMV) is the most
common of these infections.
-
Illness or trauma during pregnancy, when a
baby is born, or later in childhood. One childhood illness that
often causes hearing loss is meningitis.
-
Low birth weight.
-
Severe jaundice at birth, for example,
jaundice that requires a blood transfusion.
-
Some medications given to infants or
children to treat very serious infections.
-
Sudden loud noises and exposure to loud
noise for a long time.
-
Recurrent severe ear infections.
Approximately 25% of cases of hearing loss have
an unknown cause.
The following websites might also be useful.
Please note: Some of the information focuses adults and young
children.
Información en Español
DISCLAIMER:
Links to organizations outside of CDC are included for information
only. CDC has no control over the information at these sites. Views
and opinions of these organizations are not necessarily those of
CDC, the Department of Health and Human Services (HHS), or the U.S.
Public Health Service (PHS).
[Return to FAQs]
Q: Can an infant have both
syndromic and non-syndromic hearing loss?
No, infants with
hearing loss have either a non-syndromic form or a syndromic form.
Genetic causes of hearing loss can be
“syndromic” or “nonsyndromic”. Syndromic means that a person has other
related symptoms besides hearing loss. For example, some people with
hearing loss are also blind. Usher’s Syndrome is one example. There are
many different syndromes that have hearing loss as one of the symptoms.
“Nonsyndromic” means that the person does
not have any other symptoms related to the hearing loss. Whatever caused
the hearing loss does not cause any other symptoms. The more common type
of genetic hearing loss is “nonsyndromic” which includes 2/3 of all
genetic hearing losses. A very common “nonsyndromic” hearing loss is
caused by one gene known as Connexin 26 (abbreviated CX26). CX26 alone
is the cause in about 1/3 of all children with a non-syndromic genetic
hearing loss.
Non-genetic hearing loss
is most often caused by illness or trauma before birth or during the
birth process. Older infants and young children can also develop
non-genetic hearing loss due to illness or trauma.
Some viral infections are known to be
associated with hearing loss. These infections carry a chance of causing
infant hearing loss if the mother has the illness during pregnancy or
passes the infection to her baby during the birth process.
Cytomegalovirus (CMV) is the most common of these viral infections.
Low birth weight (less than 1500 grams or
approximately 3.3 lbs) is also associated with hearing loss. Babies with
low birth weight are often born prematurely. Prolonged mechanical
ventilation (breathing with the help of a machine and breathing tube for
long periods of time) increases the chance of hearing loss in infants.
Jaundice at birth, severe enough to
require a blood transfusion, is also associated with hearing loss. High
levels of bilirubin, a chemical in the body that causes jaundice, can
damage the nerves that control hearing. Severe distress at birth also
increases the chance for hearing loss.
One illness that carries a high chance of
causing hearing loss is meningitis. Because meningitis is an infection
of the lining of the brain and spinal cord, the sense organs of hearing
are especially sensitive to this infection and can be damaged. Also,
medications that can be damaging to hearing are sometimes given to
infants or children to treat very serious infections. These medications
are usually not given for minor illnesses such as ear infections or even
pneumonia.
Unknown causes may be genetic or
non-genetic. Because of technology and medical breakthroughs, this
category will probably get smaller and smaller as more causes of hearing
loss are understood.
For more information on medical causes of
hearing loss, please see
Causes of Hearing Loss in Children. Boy’s Town National Research
Hospital
Causes of Hearing Loss in Children. American Speech-Language-Hearing
Association
Hearing, Ear, Infections, and Deafness. National Institute for Deafness
and other Communication Disorders
Deafness and Hereditary Hearing Loss Overview. GeneReviews
[Return to FAQs]
Sorry, we can't give you medical advice. Please talk
with your doctor for questions about yourself or your family. For other
information, please contact ehdi@cdc.gov
[Return to Top]
Date: September 1, 2006
Content source: National Center on Birth Defects and Developmental
Disabilities
