In a nationwide survey on COVID-19 smell loss, over 50% of respondents still have symptoms after five years

By Olivia Trani

Since the early stages of the COVID-19 pandemic, researchers at Virginia Commonwealth University's School of Medicine have maintained a national database of patients affected by COVID-19 related smell loss. Their latest survey shows that more than half of respondents are still impacted by smell dysfunction five years after initial infection.

The preliminary report, published in the journal Otolaryngology-Head and Neck Surgery, represents the longest study on COVID-19 smell loss recovery to date.

"Our data shows that many people are still experiencing the health impacts of COVID-19 even several years later, and they are still looking for help for their symptoms," said Richard Costanzo, Ph.D., a professor emeritus in the Department of Otolaryngology at the School of Medicine and co-author of the new study. "We need to find new ways to help people suffering from smell and taste disorders, whether that's caused by COVID-19 or any future viruses."

In addition to Costanzo, the research team included Daniel Coelho, M.D., professor and vice chair for research in the Department of Otolaryngology; Evan Reiter, M.D., professor in the Department of Otolaryngology and medical director of VCU Health's Smell and Taste Disorders Center; and Aaron Tucker, M.D., a head and neck surgery resident at Rutgers New Jersey Medical School and former research fellow at VCU School of Medicine.

During the first waves of COVID-19, smell loss was one of the earliest and most common signs of infection, affecting up to 50% of patients. While most recovered their sense of smell after a few weeks or months, others had persistent smell dysfunction years after their initial infection.

"Long-term smell loss can significantly impact quality of life, and patients often report concerns over not being able to detect their own body odor or smells associated with hazards, like gas leaks, smoke or spoiled food," Reiter said. "Even partial recovery or distorted sense of smell can cause emotional distress. When meals suddenly begin to smell and taste foul, people can experience loss of appetite, nutritional deficiencies, unhealthy weight loss and depressive symptoms."

Multi-year, long COVID study on smell loss symptoms

In 2020, the VCU research team surveyed more than 2,000 adults who had tested positive for COVID-19 and self-reported smell loss. They have since continued to collect data through follow-up surveys to better understand how patient symptoms and recovery status have changed over time, specifically two years and, most recently, five years after initial smell loss symptoms were reported.

In the two-year follow-up survey, among 267 respondents, 38.2% reported complete recovery of their sense of smell, 54.3% reported partial recovery and 7.5% reported no recovery or a worsened sense of smell.

The most recent survey, conducted in late 2025, has since revealed only modest improvements to smell outcomes. Among 419 respondents, 44.2% reported complete recovery, 48.4% reported partial recovery and 7.4% reported no recovery.

Since the percentage of those with no sense of smell after five years was consistent with trends at the two-year mark, researchers suggest that the likelihood of recovery plateaus after the two-year window. Individuals who had achieved complete recovery within that window typically maintained their smell function, while the majority of people who hadn't recovered it didn't see significant changes after five years.

The likelihood of complete recovery after five years was significantly higher in participants younger than 40 years (61.7%) compared to those who were older (34%). The researchers note this may be because younger individuals typically have greater capacity for cellular regeneration in their olfactory systems.

"The body is very good at regenerating the cells we need, including cells in the olfactory system, but as we get older, regeneration slows down and recovery takes longer," Costanzo said.

The research team also did not see any connections between smell loss recovery and other factors such as a patient's initial smell loss severity, COVID-19 hospitalization and pre-existing health issues like diabetes or respiratory disease.

The future of smell loss treatment and restoration

The researchers say their findings highlight the importance of early monitoring and treatment for smell loss symptoms, as this may be the most critical window for recovering a person's sense of smell.

They also emphasize the need for more targeted therapies for smell dysfunction. Current treatments include olfactory training, where patients actively sniff distinct scents - like lemon, peppermint and peanut butter - over time to stimulate nerve pathways and retrain the brain. Costanzo and Coelho are also leading efforts to develop a neuroprosthetic nose to help patients restore their sense of smell.

"For many people, smell dysfunction from COVID-19 has evolved into a chronic condition rather than just a transient symptom of infection. We hope this research sheds a light on how pervasive smell dysfunction still is, even years after a COVID-19 infection," Coelho said. "It's important that we don't leave these people behind."

This story was originally published on the VCU Health news site.