Does toxoplasmosis cause hearing loss?

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Studies have shown a connection between toxoplasmosis and hearing loss, but the reasons aren’t fully understood. Toxoplasma infection causes inflammation and damage to the inner ear structures or auditory nerve and may also disrupt neural pathways involved in auditory processing.^[5]

Some research into latent toxoplasmosis^[6]—or an infection that has laid dormant in the host—has shown some correlation between a long-term infection and hearing loss in adults.

Studies suggest that up to 40% of infants born with the infection may eventually suffer some form of hearing loss, but the connection isn’t totally clear.^[7]

Some studies have found varying degrees of sensorineural hearing loss,^[8] meaning the loss is caused by damage to the inner ear structures or the auditory nerve. Others have found infection can disrupt the processing of auditory information^[9] in the brain.

In healthy adults, toxoplasmosis may not present any symptoms. In fact, adults may not even know they’ve been infected. If symptoms do present, they are most often characterized as mild and flu-like.^[10] In adults who are immunocompromised^[11] symptoms may be more severe and include fever, nausea, headaches and seizures.

Congenital toxoplasmosis may present diagnostic markers that healthcare providers look for during ultrasound, including hydrocephalus and intracranial calcifications.^[12]

Some infants born with congenital toxoplasmosis don’t have any symptoms at birth, but some issues may develop soon after birth or years later as a result of infection,^[13] including:

• Jaundice
• Toxoplasmosis rash
• Intellectual disabilities
• Seizures
• Vision issues
• Hearing loss

Testing for toxoplasmosis will vary depending on your age and health. Adults may receive a blood test designed to detect certain antibodies that help doctors differentiate between an acute or chronic infection. The toxoplasmosis diagnosis process may also include brain imaging, testing spinal fluid or an evaluation by an eye specialist, depending on your symptoms.^[14]

If you’re pregnant and your care team suspects you may have toxoplasmosis, they will order a blood test. To determine if the infection has been passed to the fetus, your doctor may recommend testing the amniotic fluid, a process called amniocentesis.^[15]

Healthy adults with a new toxoplasma infection may not require treatment at all. Your doctor will determine the best course of treatment if symptoms persist or become severe.

For pregnant women diagnosed with toxoplasmosis, the first goal is to prevent fetal infection by administering the antibiotic Spiramycin. If tests determine the fetus is already infected, doctors will treat with a combination of anti-parasitic and antibiotic medications.^[16] The goal is to reduce complications for both mother and baby.  Infected infants are treated with anti-parasitic medication, an antibiotic and folic acid for a year after birth.^[17]

Here are some specific tips for toxoplasmosis prevention ^[18]:

• Do not eat raw or undercooked meat.
• Rinse fruit and vegetables under running water before eating.
• Clean food prep areas with hot, soapy water.
• Wear gloves when gardening in areas that may be contaminated with cat feces.
• Wash your hands with soap and water after gardening, preparing raw meat or cleaning the litter box.
• If you are a cat owner, change the litter box daily.
• If you are pregnant, have someone else change the litter box.

Toxoplasmosis is preventable, and early detection is key to reducing complications. If you’re pregnant, immunocompromised or experiencing symptoms, consult a healthcare provider for testing and treatment options. For concerns about hearing loss related to congenital or latent toxoplasmosis, seek an evaluation from a medical professional.