COVID-Linked Loss of Smell, Taste Resolves by 3 Years After Infection

THURSDAY, Nov. 9, 2023 (HealthDay News) — There’s good news for folks who lost some of their sense of taste and smell after a bout of mild COVID: 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 was defined as an illness without any evidence of lower respiratory disease. 

Compared to 88 people who had never tested positive for COVID, 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 and the never-COVID 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 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 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 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.

SOURCE: JAMA Otolaryngology-Head and Neck Surgery, Nov. 9, 2023