Hearing loss and deafness in children

If a child's hearing is only slightly impaired, they might not understand things like whispering.

If they have moderate hearing loss, they can only hear loud sounds. And if they have severe hearing loss, they can only hear very loud sounds. Deaf children only "feel" sounds as vibrations.

Depending on the cause, either one ear or both ears may be affected. Middle ear infections are associated with other symptoms too, such as a fever and pain.

Hearing problems in newborn babies and young children often go unnoticed at first. If parents notice that there's a problem, it's usually because their child doesn't react to sounds – or has stopped reacting to sounds. Or because the child only notices that they are being spoken to when they can see the speaker's face.

Hearing loss and deafness in children can be caused by various things. Some of these causes already prevent the child's hearing from developing properly before birth. If the cause of hearing problems is hereditary (passed down from a parent to the child in their genes), the function of other organs is often affected too – such as the kidneys, eyes, heart or thyroid gland.

An unborn baby's hearing can be harmed if their mother has an infection such as German measles (rubella), toxoplasmosis or cytomegalovirus when she is pregnant. Certain antibiotics, cancer medications, narcotic drugs and alcohol can affect the development of a baby's hearing too. Another possible cause of hearing damage is getting too little oxygen during a complicated birth.

The main causes of hearing loss after birth are infections with bacteria or viruses. Young children often have temporary hearing problems if their middle ear isn't ventilated properly and fluid builds up there. This can happen if, for instance, they have a middle ear infection or enlarged tonsils or adenoids. Permanent hearing problems are less common. They may occur as a result of complications due to illnesses like meningitis, measles or mumps.

Loud sounds are generally bad for your ears. This includes regularly listening to loud music through headphones. Hearing problems can also be caused by loud banging noises – for instance, from fireworks or toy guns that bang loudly close to your ear. In rare cases hearing loss is caused by injuries to the skull.

About 1 to 3 out of 1,000 newborns have moderate or severe, permanent hearing loss in both ears. The same amount of children develop this kind of hearing problem in the first few years of life. It is estimated that about 80,000 children in Germany have a severe hearing impairment. About 32 million children are affected worldwide.

Hearing problems can develop differently over time: They may only be temporary – for instance, if caused by a middle ear infection, fluid in the ear, or earwax blocking the ear canal. Deformities or damage affecting the inner ear (before or after birth) usually lead to permanent hearing loss or deafness.

If a child has hearing loss or is deaf from birth onwards or in the first few years of their life, and their hearing problem is left untreated, it will be difficult or impossible for them to learn to speak. This can affect many areas of their life and development.

If it is thought that a child can't hear properly (anymore), their ears are examined. The doctor will take a very close look at the ears to start with. Using a special device (an otoscope), he or she will look for signs of inflammation in the auditory canal or problems in the middle ear.

To determine the type and severity of the hearing problem, various tests need to be done. For instance, the child might be asked to wear headphones and say when they can hear sounds that start off very quiet and gradually get louder. In younger children the tests can be done in a more playful way. Sometimes the doctor will strike a tuning fork and place it on the child's head and in front of their ears in a specific order. The child tells the doctor when they can no longer hear the sound. These tests allow doctors to find out whether the hearing impairment is worse in one ear than in the other, and also whether it is caused by a problem in the middle ear or in the inner ear.

To determine the exact cause and the most suitable treatment options, further tests and examinations are often done: For instance, the vibrations of the eardrum can be measured more accurately (tympanometry).

In Germany and other countries, babies are routinely given hearing tests immediately after birth in order to detect congenital ("at birth") hearing loss as early as possible.

Babies can't tell you whether or not they can hear anything, so tests like the tuning fork test aren't very helpful. Instead, screening tests in newborns measure the activity of the baby's brain or hair-like sensory cells while certain sounds are played to them. These measurements can be used to determine how well the baby can hear.

Loud sounds can harm your hearing. In children and teenagers, listening to loud music through headphones can be a particular problem. There hasn't been enough research to determine at what volume the risk of developing hearing problems increases. How often and how long the ears are exposed to loud sounds plays a role too. Experts recommend only listening to music with headphones for one hour per day at the most, and at half the maximum possible volume or less.

Congenital hearing loss (caused by genes that are passed down from a parent to the child) can't be prevented. Sometimes a couple would like to start a family and there's an increased risk that their children will be born with a hearing problem – for instance, because one or both partners (or several relatives) have had a hearing impairment or been deaf since birth. Then the couple can have genetic counseling.

To reduce the risk of their baby developing hearing problems while growing in their belly, pregnant women can

• avoid smoking, using drugs and drinking alcohol,
• talk to their doctor if they have to take medication that could harm the baby's hearing, and
• avoid infections such as German measles (rubella) and cytomegalovirus – for instance, by having a vaccine before pregnancy and paying attention to good hygiene during pregnancy.

Children should also be vaccinated against diseases that could lead to hearing loss, such as measles or mumps.

Sometimes it's possible to treat the cause of a hearing problem, such as a build-up of fluid in the middle ear.

If the cause of hearing loss can't be treated, a hearing aid can be used. Hearing aids amplify sound waves (make them "louder") and direct them towards the middle ear. This is only helpful if the ear is still able to hear something.

If someone is deaf or hearing aids don't work, special devices known as cochlear implants can generally be used. These devices make it possible to perceive acoustic stimuli (to "sense sounds").

If someone has a hearing aid or cochlear implant, something known as a wireless transmission system can improve their hearing even more. These systems pass acoustic (sound-related) information straight on to the hearing device. They can be used in schools, for instance, where they are linked to a microphone that has been set up in the classroom. In Germany and other countries, the costs are usually covered by statutory health insurers. Children with hearing impairments can make use of special support at school too.

When parents find out that their child has a hearing impairment, they are usually upset and worried about their child's development and future. Particularly if the hearing problem is severe, their lives may seem to revolve around regular appointments for tests, treatments or rehabilitation – sometimes in specialist centers or clinics that are hard to reach.

Good information is very important during this phase: Parents should be given the opportunity to have in-depth consultations with doctors about the underlying disease, as well as the pros and cons of the different treatment options. The help and support of family and friends can help too, along with professional health advice and talking to other affected parents in support groups.

Many parents find it reassuring to see that children who have a hearing impairment can develop just as well as children with normal hearing. But there are various challenges along the way: If a child finds it hard to communicate with others, they might feel left out at a regular school or when doing sports and other group activities.

Hearing aids or other hearing devices can help. But it takes time, energy and patience to learn how to use them well enough to communicate properly. Parents need to encourage and help their child here. Many parents say that this makes them feel particularly close to their child, though. They enjoy and appreciate the progress their child makes and generally find it easy to take a relaxed approach. Some parents are happy to be able to do things to improve their child's circumstances. They may also enjoy becoming actively involved in generally making things easier for people who have hearing impairments.

When people are ill or need medical advice, they usually go to see their family doctor or pediatrician first. Read about how to find the right doctor, how to prepare for the appointment and what to remember.