Feb. 24 (UPI) — People given a COVID-19 vaccine are not at higher-than-normal risk for developing sudden hearing loss, a study published Thursday by JAMA Otolaryngology-Head & Neck Surgery found.
Of the more than 185 million vaccine doses administered nationally as of July 16, 2021, 555 recipients developed sudden sensorineural hearing loss, the data showed.
This corresponds to an estimated 28 cases of sudden sensorineural hearing loss per 100,000 people per year, which is about the same as the pre-pandemic, pre-vaccine rate in the United States, research suggests.
“We did not find an association between sudden hearing loss and COVID-19 vaccination,” study co-author Dr. Eric Formeister told UPI by email.
Still, the study does not “definitively answer whether or not there is a true association between vaccination and hearing loss,” said Formeister, an otology and neurotology fellow at Johns Hopkins Medicine in Baltimore.
This would require a larger study comparing rates of sudden hearing loss among vaccinated and unvaccinated people, he said.
Sudden sensorineural, or “inner ear,” hearing loss is an unexplained, rapid loss of hearing that occurs either all at once or over a few days, usually in one ear, according to the National Institute on Deafness and Other Communication Disorders.
It occurs because there is something wrong with the sensory organs of the inner ear, the institute says.
All three currently available COVID-19 vaccines, from Johnson & Johnson, Moderna and Pfizer-BioNTech, have been linked with other ear-related side effects, including tinnitus, dizziness and vertigo, the Centers for Disease Control and Prevention reports.
However, the agency has described these side effects as “extremely rare.”
In the first analysis, conducted in the United States, the researchers analyzed reports of sudden sensorineural hearing loss submitted to the CDC’s Vaccine Adverse Events Reporting System between Dec. 14, 2020, and July 16 last year.
Of the 555 confirmed cases of this form of hearing loss following vaccination, 305 occurred in women, the data showed.
Most occurred within roughly six days after receiving the vaccine, the researchers said.
Affected vaccine recipients recovered with treatment, which typically involves the corticosteroids, according to the National Institute on Deafness and Other Communication Disorders.
The side effect was slightly more common with the Johnson & Johnson vaccine than with the Moderna and Pfizer-BioNTech shots, they said.
A separate study in Israel, also published Thursday by JAMA Otolaryngology-Head & Neck Surgery, found that there were 170 cases of sudden sensorineural hearing loss among the recipients of more than 2.6 million doses of the Pfizer-BioNTech vaccine.
This represents a “small” increase in the risk for this type of hearing loss after receiving the Pfizer-BioNTech shot compared with what would exist normally, researchers on this study said.
In the Israeli study, women were found to be at slightly higher risk for sudden sensorineural hearing loss after getting the Pfizer-BioNTech vaccine, the researchers said.
The side effect was more common following the first dose than the second, they said.
Collectively, the findings of both studies do not indicate a need to avoid vaccination due to the risk for sudden hearing loss, the researchers said.
“There is a possible connection between the COVID vaccination and sudden hearing loss,” the co-author of the Israeli study, Dr. Yoav Yanir, told UPI in an email.
“Having said that, this risk is small, and the advantages of vaccination outweigh the potential elevation in the risk for hearing loss,” said Yanir, an otolaryngology-head and neck surgeon at Carmel Medical Center in Haifa.