Hearing loss may be a sequel to Covid; understand

Total or partial loss of hearing, usually in one ear, suddenly and without a definite cause. Accompanied by this, the appearance of a constant tinnitus on the affected side. In some cases, there is still a feeling of vertigo and imbalance.

These are characteristics of sudden deafness, a condition in which a person suddenly loses hearing and may never hear fully again. There are countless causes of the problem – among which is Covid-19.

The appearance of hearing loss cases went through a boom in the years of the Sars-CoV-2 pandemic, the virus that causes Covid-19.

Rubens de Brito, professor at the Faculty of Medicine at USP (University of São Paulo) and coordinator of the Otorhinolaryngology Center at Hospital Sírio-Libanês, says that the exponential growth in the last two years was not normal compared to what was seen before.

“They were two very atypical years. You have years and years of a certain number of annual cases and, at the time of the pandemic, a very significant increase. Because of this, it is possible that there is a strong relationship with the virus”, he explains.

However, sudden deafness is not just a consequence of Sars-CoV-2. In reality, there are countless causes and, therefore, it can be difficult to define the origin of the disorder. Other viruses, such as herpes and herpes zoster, are also known to cause the disorder.

Furthermore, one detail is that, with the causative agent defined, the term sudden deafness becomes inappropriate, explains Arthur Menino Castilho, otorhinolaryngologist and specialist at the Brazilian Association of Otorhinolaryngology and Cervico-Facial Surgery (ABORL-CCF).

“When you find the cause, it’s not sudden deafness. It’s deafness caused by a certain agent. In the case of Covid, if you define that it was this infection, it can no longer be called sudden deafness”, says Castilho.

Viral infections, such as Covid-19, can affect the electrical part of hearing and then lead to hearing loss. “The sensory cells, [aquelas] nerves in our labyrinth become inflamed and lose function in some viral infections”, explains Brito.

The disorder is treatable. One of the main means is corticoids that act, regardless of the cause, in controlling the inflammatory process that causes sudden deafness. “The inner part of your ear will inflame, and the corticoid can stop this process that damages the auditory cells”, says Castilho.

In other cases, the condition may linger. In the case of Covid, for example, hearing loss may already appear in the acute period of the infection and continue as a sequel to the viral infection. Therefore, it is important to pay attention to the symptoms to avoid difficulties in reversing the drop in the ability to hear.

Brito claims that some people have a more serious picture of the loss from the beginning, which makes healing difficult. Others take a long time to see a doctor, worsening the chances of successful treatment.

Therefore, the USP professor recommends a quick search for specialized care in cases of suspected sudden deafness. “If you have unexplained hearing loss and that loss persists the next day, you should see a doctor.”

Although hearing loss as a result of Covid-19 is already observed, there is a lack of further studies on the subject. Castilho states that, in Brazil, there is no consolidated data on patients affected by hearing problems associated with Sars-CoV-2. In the United States, there is even information, but there is still little.

The scarcity of research leaves doubts open. One of them is whether different variants of the virus can lead to greater cases of hearing loss. Castilho, for example, states that there are some indications that omicron causes a greater chance of a problem in the ear, but research is needed to really confirm whether this occurs or not.