Study: COVID Can Infect the Inner Ear

COVID-19 can cause a range of symptoms. In some cases, it can even lead to ear-related symptoms like hearing loss, ringing in the ears, dizziness, and balance issues. Reports of these symptoms have led researchers to suspect that the virus could infect the inner ear.

Now, a new study from MIT and Massachusetts Eye and Ear has found that SARS-CoV-2, the virus that causes COVID-19, does indeed have the ability to get into the ear and cause infection.

What the Study Found

The study, which was published in the journal Communications Medicine, examined inner ear tissue from 10 COVID-19 patients with ear symptoms such as hearing loss, balance issues, and ringing in the ears (also known as tinnitus). The researchers also used cellular models and mouse inner ear tissue. 

The researchers discovered that SARS-CoV-2 can infect the inner ear’s cells and even its hair cells, which help with hearing and balance. They also found that the pattern of infection that was seen with human inner ear tissue was consistent with the symptoms reported by patients.

By using human and mouse inner ear tissue as well as generated cellular models, the researchers were able to show how it’s possible for SARS-CoV-2 to get into the inner ear and infect certain parts of it.

Based on their findings, the researchers concluded that “inner ear infection may underlie COVID-19-associated problems with hearing and balance."

COVID Ear Symptoms

Currently, there are no ear-related symptoms on the Centers for Disease Control and Prevention (CDC)’s list of COVID-19 symptoms, which includes:

• Fever or chills
• Cough
• Shortness of breath or difficulty breathing
• Fatigue
• Muscle or body aches
• Headache
• New loss of taste or smell
• Sore throat
• Congestion or runny nose
• Nausea or vomiting
• Diarrhea

However, the CDC also states that its list “does not include all possible symptoms.” Furthermore, the organization also notes that dizziness on standing is a possible symptom of long COVID. 

There have been several case reports of patients developing tinnitus after being sick with COVID-19, including one of a 35-year-old woman in Qatar who developed hearing loss and tinnitus when she had the virus. Her symptoms persisted even after she recovered from the virus and hearing tests confirmed that she had hearing loss at low frequencies in her left ear. 

A meta-analysis published in the International Journal of Audiology in March 2021 analyzed data from 28 case reports and 28 cross-sectional studies. The results indicated that 7.6% of patients with COVID-19 had hearing loss, 14.8% experienced tinnitus, and 7.2% had vertigo after having the virus.

John Sellick, DO, an infectious disease expert and a professor of medicine at the University at Buffalo/SUNY, tells Verywell that “Tinnitus, in particular, seems to be fairly common with long-haulers. The question is, is this going to resolve or not?”

Other Causes of Ear Infections

Scott Shapiro, MD, an otolaryngologist (ear, nose, and throat specialist) at the Rutgers Robert Wood Johnson Medical School, tells Verywell that other viruses, like those that cause colds, the flu, and measles and mumps, can all infect the inner ear as well.

According to infectious disease expert Amesh A. Adalja, MD, a senior scholar at the Johns Hopkins Center for Health Security, “the receptor that SARS-CoV-2 uses to enter cells is widespread, so it’s not surprising to see that infection of the cells of the inner ear is possible.

Adalja says that many viruses "are able to cause disease in the inner ear but it is unclear how many do it through direct viral infection.”

Shapiro says that while the findings of the new study are “not surprising,” they're still important because they’re the first to prove that COVID-19 can affect this part of the ear. "We see a lot of patients that report ear-related symptoms after having COVID-19," says Shapiro. "But we’ve never been able to say mechanistically that the virus actually gets into the cells of the inner ear."

When to See Your Doctor

If you have ear symptoms, Shapiro recommends seeing your primary care physician—especially if you have hearing loss or your symptoms are not getting better because in this case, “it’s usually inner ear hearing loss and it’s time-sensitive to treat."

However, Shapiro also points out that it can be “hard for doctors to pin" ear symptoms on COVID, partly because “tinnitus and hearing loss are common” even in people who haven't had the virus recently. That’s why he recommends getting evaluated if you have any hearing changes.

Sellick says that the link between ear-related issues and COVID-19 “is another reason to get vaccinated,” and reminds folks that “having ear-related issues is not a good thing.”

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.