The coronavirus may be able to infect the inner ear

Image: Christine Daniloff, MIT

Covid-19 may be able to infect the inner ear and cause auditory and balance problems.

A study published in Communications Medicine examined 10 patients from Massachusetts Eye and Ear specialty hospital who were experiencing hearing problems, such as hearing loss and tinnitus, and who had tested positive for the coronavirus. Study co-lead Konstantina Stankovic, who was working with patients with hearing problems said, "It was very unclear at the time whether this was causally related or coincidental, because hearing loss and tinnitus are so common."

Possible routes to the inner ear include a tube from the nose to the ear in which the virus could travel, or through small openings in nerves that would allow the virus "to enter the brain space and infect cranial nerves," including ones that lead to the inner ear, the study says.

The researchers developed models of various inner-ear cells, and they found that that the virus was capable of infecting two types of cells, one of which aids in "sensing head movement and maintaining balance," they report.

“Having the models is the first step, and this work opens a path now for working with . . . other viruses that affect hearing,” said Lee Gehrke, the study's other co-lead. The researchers also said the models may help to test future possible inner ear treatments for various viral infections.