Thursday this week marks World Hepatitis Day. Hepatitis results when one or more of the following five viruses enter the body and trigger an aggressive autoimmune response by your liver, which can in turn lead to serious liver damage:
- Hepatitis A (HAV)
- Hepatitis B (HBV)
- Hepatitis C (HCV)
- Hepatitis D (only affects people who already have HBV)
- Hepatitis E
Of these, HBV has the strongest link to a risk of hearing loss, so this is the form of hepatitis on which we’ll focus.
Hepatitis B basics
Approximately one in three people worldwide have been diagnosed with hepatitis B. HBV is spread through contact with infected blood and other bodily fluids. Pregnant women with HBV sometimes transmit the virus to their babies (often during birth). Once acquired, HBV can take two forms:
- Acute: New infection that lasts less than six months and can resolved on its own without further complications, leaving the host immune and no longer contagious. Approximately 95 percent of those infected as teens or adults will spontaneously and completely recover.
- Chronic: If infection continues more than six months, the host can transmit to others and faces a variety of risks to their livers (e.g., cirrhosis or cancer). Those infected at birth or before the age of five are likeliest to experience chronic HBV.
Fortunately, routine hepatitis B vaccination in the United States has led to a drastic reduction in new infections (by more than 200,000 cases per year since the 1980s). Other preventative measures include using condoms during sex, avoiding contact with others’ blood, and not sharing needles.
The risk of hearing loss for HBV patients
Complications from HBV including sensorineural hearing loss, likely due to vascular inflammation restricting the blood flow necessary to keep your inner ears functioning. Sensorineural refers to conditions affecting the inner ear or neural pathways, meaning sound transmits through your outer and middle ear normally, but your inner ear doesn’t properly conduct this input to your brain for processing. It is usually caused by auditory nerve, cochlear, or hair cell damage. Hair cells are particularly vulnerable to a lack of sufficient blood supply, and once they “die” they cannot be regenerated.
The following are signs you might have a sensorineural hearing loss:
- Loss of ability to understand speech clearly
- Difficulty understanding high-pitched voices (e.g., small children)
- Challenge to hear over background noise or in crowds
- Trouble discerning between consonants like s, f, th, and sh
If you know you have hepatitis B, it’s a good idea to get your hearing checked regularly, even if you aren’t struggling to hear yet. If your HBV is chronic, your hearing might decline over time. The sooner you discover a hearing loss the greater the likelihood treatment with hearing aids will be effective.