Fading sound

Youngsters learn to massage their ears under the guidance of medical specialists in Pingdingshan, Henan province. [Photo provided to China Daily]

Causes of hearing loss include aging, noise, genetic abnormality, head injury, birth asphyxia (lack of oxygen at the time of birth), infections and ototoxic drugs. Measles, meningitis and rubella among others can also cause hearing loss.

Yet half of all hearing loss cases are avoidable through primary prevention, a World Health Organization report says.

"We cannot avoid deafness caused by genetics or aging, but there is much we can do to prevent other acquired deafness, especially among children and young people," says Hu Xiangyang, president with the China Rehabilitation and Research Center for Deaf Children in Beijing.

China has been making great efforts to reduce deafness through raising public awareness of threats to hearing, immunizing children and women against hearing-harming diseases and improving antenatal and prenatal care, but there is still a long way to go, Hu says.

Infections and diseases can be prevented or cured before they cause severe or permanent hearing loss. Possibility of ear injuries and excessive noise exposure can also be controlled, Gu adds.

In Zhang's case, it can be a special type of gene-related hearing loss that infects children between the ages of 4 and 10, or it can be caused by ear infection and nerve damage because of fever and sinusitis, or other undetected diseases.

Recently, Gu noticed his 5-year-old son often went off from conversations with others and didn't respond when Gu called him.

Checks revealed that the boy had secretory otitis media, or glue ear, a condition where the middle ear fills with glue-like fluid and can cause permanent hearing loss.

The condition happens when a thin tube that connects the ear and nose doesn't work properly, or when extra mucus is secreted after a cold, cough, ear infection or sinusitis.

It usually clears out within a short period of time without treatment, but sometimes it reoccurs often or persists. Then the fluid in the middle ear will constantly dampen the vibration of the eardrum, weaken hearing and sometimes bring about permanent damage to the ear.

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