A quick look at the website of Deaf SA — South Africa’s leading federation for the deaf — reveals statistics that make for grim reading. As many as 600 000 South Africans use sign language as their primary means of communication. One baby in 10 is born with some sort of a hearing problem.
Many children suffering from deafness are diagnosed only when they reach four years of age and, in some cases, only when they reach eight years — something that obviously impedes their language, social and intellectual development. What causes deafness and why is it far more common than many of us realise?
From a medical point of view, deafness can be divided into two broad categories: conductive hearing loss and sensorineural hearing loss. It is also common to have a combination of both. Conductive hearing loss results when sound vibrations are not discernable to the tiny bones in the middle ear. This happens when there’s something blocking the external ear canal, such as wax or fluid in the middle ear as a result of an ear infection, or a build-up of calcium on the small bones of the middle ear. When conductive hearing loss occurs, it usually does not result in a total hearing loss, but sounds are far weaker, muffled and distorted than normal.
Sensorineural hearing loss occurs when the nerve linking the inner ear to the brain fails to function as it should. This can also result in a loss of loudness and clarity of sound, but more often leads to total deafness.
Other causes of deafness include hereditary factors that cause one in 800 babies to be born profoundly deaf, the reasons for which are largely unknown. What is known is that there are no hard-and-fast rules governing genetic causes: deaf adults often have hearing children and hearing adults often have deaf children.
Otosclerosis, also a hereditary disease, is another common cause of deafness that can be permanent. It affects the middle and the inner ear and causes bony sponges to grow. Meningitis, shingles and cytomegalovirus (CMV) are also well-known culprits. And conditions that can put children’s’ hearing at risk are mumps and German measles (rubella) during their mother’s pregnancy.
The reason we sometimes need to raise our voices to be understood by elderly folk is often a condition called presbycusis. Believed to be genetic, it is responsible for the slow decay of sensitive hair cells that line the inner ear. This kind of decay can also be caused by diabetes and circulatory problems.
Injuries to the ear can obviously put a person’s hearing ability at risk. Perforated eardrums and damage to the auditory nerve caused by being in an accident or playing contact sports is common, as is permanent damage from repeated exposure to loud noises through industrial machinery or heavily amplified music. As regards the latter, MP3 players have recently been implicated in hearing loss in adolescents.
Treatment options vary. Conductive hearing loss is treated by removing the cause of the blockage — rinsing out the wax in the ear canal, or getting rid of the fluid in the middle ear through inserting grommets in the eardrum. Otosclerosis can be treated with surgery, but the only way to treat sensorineural hearing loss is through the use of a hearing aid.
Some people benefit from a cochlear implant, which requires thin wires to be implanted inside the inner ear. These devices connect to the auditory nerve and convert sound into electrical impulses. But considering the high cost of surgery, this is hardly an option for the majority of South Africans. Their world is one of silence: not just the silence of the absence of sound, but also the silence about their plight that sees 75% of the deaf community being functionally illiterate, and 70% of that community being unemployed. It’s time the rest of us hear their plight.
This article originally appeared in the Mail & Guardian newspaper as a sponsored feature
Deafness will be discussed on Bonitas House Call on SABC2 on May 21 at 9am