Loss of taste, smell resolves within 3 years of COVID-19 infection, study shows

There's good news for folks who lost some of their sense of taste and smell after a bout of mild COVID-19: New research shows this side effect largely resolves by three years after infection.

Italian researchers looked at post-COVID outcomes for 88 people who lost their sense of taste and smell early in in the pandemic, with everyone contracting "mild" COVID-19 during March and April of 2020. Patients averaged 49 years of age at the study's start.

Mild COVID-19 was defined as an illness without any evidence of lower respiratory disease.

Compared to 88 people who had never tested positive for COVID-19, rates of loss of smell and/or taste (as measured by standard tests) were roughly equal three years later, said a team led by Dr. Paolo Boscolo-Rizzo of the University of Trieste in Italy.

"At the 3-year study end point, olfactory dysfunction was comparable between both groups," the group reported Nov. 9 in the journal JAMA Otolaryngology-Head and Neck Surgery.

As for a loss of the sense of taste ("gustatory dysfunction"), Boscolo-Rizzo's group similarly found "no significant differences" between folks who'd had mild COVID-19 and the never-COVID-19 groups, two and three years later.

The findings should be welcome news because, until now, "no data exist regarding psychophysical assessment of olfactory dysfunction and gustatory dysfunction after COVID-19, to our knowledge," the team said.

While many patients who went through a bout of COVID-19 did complain of deadened senses of taste and smell, the new study finds that sense recovery does happen over time.

For example, while about two-thirds (64.8%) of people with mild COVID-19 said they'd lost their sense of smell and/or taste at the time they were ill, that number dropped to about 32% one year later, then to 20.5% two years after infection, and finally to about 16% three years later.

That last number differed only slightly from the group of people who had never tested positive for COVID-19, the researchers noted.

The bottom line, according to the researchers: Former COVID-19 patients "should be reassured that a recovery of olfaction appears to continue over 3 years after initial infection."

More information

Find out more about COVID-linked sensory issues at the University of Utah Health.