In March of last year, Gregory Poland, MD, was grappling with what he described as unrelenting symptoms of tinnitus that he developed shortly after receiving his second dose of an mRNA COVID-19 vaccine in early 2021.
About a year-and-a-half later, after his first COVID infection, Poland told that his tinnitus has worsened. Indeed, have shown that COVID itself can cause tinnitus.
Poland -- the director of the Mayo Clinic's Vaccine Research Group in Rochester, Minnesota, and editor-in-chief of the journal Vaccine -- said his symptoms now fluctuate and reach more intense levels throughout the day. He said it sounds like having a high-pitched dog whistle blown into his ears 24 hours a day, 7 days a week.
"I'm on a road that I don't know where it leads," Poland said. "Is this going to get worse? Am I going to lose hearing?"
But Poland said sharing his story is not about him.
Since speaking out about his own experience, Poland said he has received hundreds of emails from people all over the world claiming they, too, developed tinnitus soon after COVID vaccination. And though pro-vaccine himself, Poland said he would like to see more research to determine whether there may be any potential link.
A search of the yielded just shy of 17,000 reports of tinnitus following COVID vaccination in the U.S. Importantly, "VAERS reports alone cannot be used to determine if a vaccine caused or contributed to an adverse event or illness," according to the CDC. And reports "may contain information that is incomplete, inaccurate, coincidental, or unverifiable."
At the same time, Poland said that given the plethora of reports in VAERS, he feels it is "frustrating" that the topic has "attracted little in the way of research."
Indeed, a search of PubMed indicated a dearth of research in the area.
One physician who has recently looked into the topic is Doris Lin, MD, of the University of North Carolina at Chapel Hill. Lin's work, "Tinnitus cases after COVID-19 vaccine administration, one institution's observations," was earlier this year.
"I began seeing a lot of patients during the pandemic with bothersome tinnitus," Lin told in an email. "Some of the other providers here, including the audiologists, noted that some of the patients were associating the onset or worsening of their tinnitus with the COVID vaccine. We wanted to see how many patients and how many were even possibly related."
The study involved the search of a hospital electronic medical record database using diagnosis codes for tinnitus and COVID vaccines from December 1, 2020 through December 31, 2021, with 1,254 patients being identified, Lin and a co-author reported. After chart review, 27 cases were identified with self-reported tinnitus onset or worsening shortly after COVID vaccination (within 25 minutes to 4 weeks). Seven of these patients were male, and 20 were female. They ranged in age from 41 to 84 years, with a median age of 59.
However, Lin and a co-author reported that a correlation could not be proven with such few cases.
"The retrospective study did confirm the low incidence of tinnitus after COVID vaccination but certainly was not able to answer if it was caused by the COVID vaccination itself," Lin told .
Lin did note that there were other patients who self-attributed their tinnitus to a COVID vaccine, but that the research team had to cap the inclusion criteria time frame at 4 weeks post-vaccination, "as beyond that time frame, there really was too much recall bias and too many other possible explanations."
Lin added that, currently, she does not have additional research planned specifically related to tinnitus and COVID vaccines.
As for the CDC, a spokesperson told in an email that the agency is aware of reports to VAERS of tinnitus following COVID vaccination, adding that tinnitus is a common condition, is heterogenous in presentation and course, and is without a discernable cause in many cases.
"Hundreds of millions of people have received COVID-19 vaccinations under the most intensive monitoring in U.S. history," the spokesperson said. "Because so many people have been vaccinated and because tinnitus is so common in the population, temporally-associated cases are expected, with some expected to occur shortly after vaccination."
The spokesperson noted that in order to further evaluate reports of tinnitus following COVID-19 vaccination, the CDC analyzed data from its .
"Unlike VAERS, which relies primarily on voluntary reports from healthcare providers, patients, and others, the VSD uses data from electronic health records," the spokesperson said. "Consequently, the VSD data are less likely to be affected by the reporting biases and other biases that impact spontaneous reporting patterns to VAERS and data quality."
The VSD analysis focused on "clustering of tinnitus diagnoses in COVID-19 vaccinated patients during a post-vaccination observation period out to 70 days after vaccination," the spokesperson explained. "In the VSD's patient population of approximately 12 million people with 6.6 million COVID-19 vaccine doses administered, to date no clustering of tinnitus diagnoses has been observed post-vaccination."
"Currently, the information from vaccine safety monitoring systems does not suggest a link between COVID-19 vaccination and tinnitus," the spokesperson said. "CDC will continue to monitor the safety of COVID-19 vaccines and continue to evaluate the outcome of tinnitus as additional data are collected."
A spokesperson for Pfizer echoed that "tinnitus cases have been reviewed and no causal association to the COVID-19 vaccine has been established." Moderna did not immediately respond to a request for comment.
For Poland, when his symptoms are "maddening," he said he often turns to certain sounds played through a set of earbuds. Crickets and orange noise have tended to work best, he said.
Poland said the potential relationship represents a "research and medical desert, for which research funding needs to be provided," he said. Tinnitus cannot be seen or measured in the same way that other conditions can be, and there is little in the way of evidence-based treatment, he added.
"For anything we do in medicine, we should inform people about the pros as we understand them, and the cons," Poland said.
"Transparency," he added, is "where trust is built in medicine."