What viral illnesses can cause hearing loss?

Viral Causes of Hearing Loss

Several viral infections can cause hearing loss, with cytomegalovirus (CMV) being the most significant cause of congenital and childhood sensorineural hearing loss, followed by herpes viruses, rubella, measles, and mumps. 1

Congenital Viral Infections

Cytomegalovirus (CMV)

• Most significant viral cause of childhood hearing loss - accounts for 13-20% of all childhood-onset sensorineural hearing loss 1
• Occurs in approximately 1 in 200 live births in the United States 1
• Hearing loss presentation:
  • Can be present at birth, late-onset, or progressive 1
  • Can be unilateral or bilateral
  • Often severe to profound in degree 1
  • Only 57% of infants with CMV who develop hearing loss will fail newborn hearing screening 1
• Risk factors:
  • Symptomatic CMV: 32.8-40% develop hearing loss 1
  • Asymptomatic CMV: 9.9-25% develop hearing loss 1
  • Changes in hearing can occur as late as 18 years of age 1

Other Congenital Viral Infections

• Rubella (now rare due to vaccination) 2
• Herpes 1
• Syphilis 1
• Toxoplasmosis 1

Acquired Viral Infections

Mumps

• Well-documented cause of sensorineural hearing loss 3, 4
• Can cause permanent bilateral sensorineural hearing loss 3
• Often goes unnoticed until speech/language delays develop 3

Other Acquired Viral Infections

• Measles 3, 4
• Herpes zoster (shingles) 3, 5
• Varicella-zoster virus 5
• Influenza viruses 3, 5
• Common cold viruses 4

Post-Infectious Meningitis

• Bacterial and viral (especially herpes viruses and varicella) meningitis can cause sensorineural hearing loss 1
• Considered a risk factor for delayed-onset or progressive hearing loss 1

Mechanisms of Viral-Induced Hearing Loss

Viruses can cause hearing loss through several mechanisms:

• Direct damage to inner ear structures 6
• Inflammatory responses causing damage 6
• Increased susceptibility to bacterial or fungal infections 6

Clinical Presentation and Diagnosis

• Hearing loss can be:
  • Sensorineural (most common)
  • Conductive
  • Mixed 6
• Symptoms may include:
  • Ear fullness/pressure sensation 7
  • Hearing difficulties, especially in noisy environments 7
  • Discomfort or mild pain 7
  • Vestibular symptoms (dizziness, disequilibrium) 7

Prevention and Management

Prevention

• Vaccination has significantly reduced hearing loss from rubella, measles, and mumps 2, 4
• Universal newborn CMV screening is recommended to identify at-risk infants 1
• CMV testing should be performed before 21 days of age to distinguish congenital from acquired infection 1

Management

• Early antiviral treatment for symptomatic CMV may be beneficial 2
• Children with congenital hearing loss or hearing loss developing in the first year should be evaluated for asymptomatic CMV infection 2
• Regular follow-up is essential for children with risk factors for hearing loss 1
• Watchful waiting for post-infectious ear fullness and hearing issues for the first 3 months 7

Risk Indicators for Delayed-Onset or Progressive Hearing Loss

The American Academy of Pediatrics identifies several viral-related risk factors:

• In utero infections (CMV, herpes, rubella, syphilis, toxoplasmosis) 1
• Culture-positive postnatal infections associated with sensorineural hearing loss 1
• Caregiver concern regarding hearing, speech, language, or developmental delay 1

Key Points for Clinical Practice

• CMV is now the most common viral cause of congenital hearing loss since rubella vaccination became widespread 1, 2
• Hearing loss from viral infections can be delayed-onset and progressive, requiring ongoing monitoring 1
• Early identification through universal newborn hearing screening and CMV screening is crucial for timely intervention 1
• Vaccination remains the most effective prevention strategy for many viral causes of hearing loss 2, 4