What you need to know about viral causes of hearing loss

It's a common misconception that hearing loss can only be caused by exposure to loud noises, old age, or a prenatal damage. However, many people experience hearing loss due to infections. Many of these infections are caused by viruses that affect the cochlea, blood vessels in the ear, or other parts of the body that deal with hearing.

There is no single virus that causes hearing loss, and not everyone's experience is the same. While one person might survive a serious childhood infection and end up with profound hearing loss or even deaf, another might experience a virus later in life. Hearing loss comes in many forms, and while we can draw patterns between them, every case is unique.

While there is no surefire way to avoid hearing loss, staying vigilant and recognizing symptoms of viruses early on can prevent them from spreading further. Proper diagnosis and treatment are also necessary, so it's best to know what kinds of viruses cause hearing loss in the first place.

What kind of viruses cause hearing loss?

Many different types of illnesses can cause hearing loss, but there are two categories for sorting viruses with this effect. Some viruses can cause congenital hearing loss, while others result in acquired hearing loss later in life. Certain viruses can even fall into both of these categories. When dealing with hearing loss, these categories help doctors determine what viral infection is present.

While some of these infections are rare, others might be more prevalent. For example, Cytomegalovirus, a virus that causes congenital hearing loss in children, affects about one out of every 100 babies.

Viruses that cause hearing loss

As mentioned above, viral causes of hearing loss can vary between congenital, acquired, and both. It's important to differentiate between these three in order to successfully diagnose someone. If you or a loved one is suffering from sudden SNHL or sudden sensorineural hearing loss, it is vital that you seek help from a professional. While you can find information about potential viruses online, only a doctor can diagnose and treat you.

Children who suffer from congenital viruses are at a greater risk of hearing loss. These viruses can include:

• German Measles, or Rubella. An RNA virus, Rubella is transmitted through fluids like phlegm and saliva. If a mother is infected with Rubella during pregnancy, her child becomes at risk of obtaining the congenital form of the virus. Rubella is also one of the TORCHS group, and hearing loss typically sets in 6-12 months after birth.
• Cytomegalovirus. This DNA virus is responsible for most non-genetic cases of SNHL in infants and children. CMV belongs to TORCHS, a group of viruses that frequently cause hearing loss in children. In many cases, CMV-infected child will develop hearing loss after their SNHL screenings are finished. For this reason, it is important that parents remain vigilant if they have a CMV-positive child.
• Lymphocytic Choriomeningitis Virus (LCMV). While not transmittable through human-to-human contact, this RNA virus is transmitted through contact with rat feces, urine, and saliva. While hearing loss isn't as common in children infected with LCMV, it is a well-documented congenital effect.

Children and adults suffering from SNHL can also be diagnosed with the following viruses, which cause both congenital and acquired hearing loss after infection.

• HSV Types 1 & 2. Both HSV one and two belong to the herpesvirus family, and this virus can occur in children and adults. While adults might acquire this virus through contact, children with HSV1 or HSV2-positive mothers can become infected in-utero. To prevent infection of children from their mothers, therapies, medications, and cesarean births are recommended.
• Human Immunodeficiency Virus (HIV). A well-known RNA virus that can lead to AIDS, along with a variety of other conditions and illnesses. By killing T-cells, children and adults suffering from HIV become susceptible to opportunistic infections. Hearing loss is a common side effect of HIV, with 2/3 of HIV-positive children suffering SNHL, and 1/2 of that group suffering from developed hearing loss.

The last group of viruses includes viruses that cause acquired hearing loss. This form of hearing loss typically occurs in those who are older and are not suffering from a congenital virus.

• West Nile Virus. Related to both yellow and dengue fever, West Nile is an RNA virus transmitted through insects -- typically mosquitos. While hearing loss resulting from a West Nile infection is rare, every case but one ended with the patient spontaneously recovering from their hearing loss.
• Varicella Zoster Virus (VZV). A DNA virus also belonging to the herpes family. Zoster and shingles are both forms of the reactivated VZV. VZV can cause issues with the nerves of the face, auditory canal, and tongue. In some cases, the resulting hearing loss was reversed or alleviated through the use of corticosteroids and other medications.
• Measles (Rubeola). An RNA virus that previously accounted for 5-10% of all US cases of profound hearing loss. While vaccination has rendered this virus nearly extinct in the United States, outbreaks have occurred due to a number of factors. In places where measles vaccinations are not widespread, the virus continues to cause hearing loss.
• Mumps. Belonging to the same family that includes measles, mumps is an RNA virus that can cause a host of problems, including SNHL. With proper diagnosis and treatment, there is a chance this hearing loss can be reversed, but some cases become permanent.

It's also worth noting that viruses do not typically cause conductive hearing loss. This type of hearing loss is usually caused by fluid, bacterial infections, earwax buildup, and injuries to the eardrum.

Why sudden hearing loss warrants treatment

If hearing loss occurs in either of your ears, it is important that you take the matter seriously. If left unchecked, your condition can quickly worsen and result in serious side effects, including permanent hearing loss. To avoid hearing impairment, it is recommended that you seek help from a hearing care provider as soon as possible.

If you're concerned about the quality of your hearing, consider getting an audiogram. Online tests like our Signia hearing test can also be used to help determine if you are suffering from hearing loss. If you've recently noticed a drop in hearing ability, do a test to make sure there is nothing wrong. If you encounter any form of hearing loss, be sure to bring it up with a medical professional. It might be a symptom of a larger issue.

Preventing deafness and hearing loss

There are no surefire ways to prevent hearing loss and deafness. Certain congenital conditions leave no room for prevention, especially if the mother isn't aware she is carrying the virus. Likewise, it can be difficult to know you are suffering from a latent virus, as they show little to no symptoms. Getting tested regularly and staying on top of your health is the best preventative measure in these cases.

It is also important that you get yourself and your children vaccinated. While controversy has spread regarding this practice, even a single case of mumps or measles can result in acquired hearing loss. It is better to be safe than sorry in these situations, especially when your hearing is at risk.

Wider immunity should also be taken into account in these situations; even if your children recover from measles, an immunodeficient child might catch the virus and suffer serious health issues.

Along with preventing viral infections, it is also necessary to protect your ears. Avoid spending a lot of time in noisy environments and use protection while working in loud conditions. Get professional audiograms every few years, and use online hearing tests as benchmarks. While you cannot fully prevent hearing loss, you can shield yourself against it.

If you don’t know where to get a professional audiogram, you can have a look at our Signia store locator to find the nearest or most convenient location.