COVID-19 doesn’t produce a distinctive body odor or scent you can detect on yourself or others. What the virus does do, often dramatically, is change how things smell to you. Millions of people who caught COVID found that familiar scents suddenly smelled wrong, disappeared entirely, or were replaced by phantom odors that weren’t really there. These distortions are what most people mean when they search for what COVID “smells like,” and the descriptions are remarkably consistent: burnt rubber, garbage, rotting food, cigarette smoke, and harsh chemicals.
How COVID Changes Your Sense of Smell
COVID affects smell in three distinct ways, and many people experience more than one over the course of their illness and recovery.
- Anosmia: A complete loss of smell. Things that should have a strong odor, like coffee, garlic, or perfume, register as nothing at all.
- Parosmia: Real smells get scrambled. Food cooking in the oven might smell rotten. A loved one’s shampoo might smell like chemicals. The scent is there, but your brain interprets it incorrectly.
- Phantosmia: You smell things that don’t exist. There’s no source, but you detect burning rubber, garbage, burnt toast, tobacco smoke, metallic odors, or a moldy, stale quality in the air around you.
Parosmia and phantosmia tend to overlap, and both skew heavily toward unpleasant smells. People rarely report phantom smells that are neutral or pleasant. The most commonly described odors are burning, rotting, and chemical in nature. Warm cookies fresh from the oven, for example, might smell rotten to someone with parosmia. Previously enjoyable scents become overpowering and repulsive.
Why COVID Targets Smell So Specifically
Early in the pandemic, researchers assumed the virus was directly damaging the nerve cells responsible for detecting odors. The reality turned out to be more indirect. SARS-CoV-2 primarily infects the support cells in your nasal lining, not the smell-detecting neurons themselves. These support cells act like scaffolding and supply lines for the sensory neurons. When the virus knocks them out, the neurons lose the structural and chemical support they need to function properly.
The neurons essentially go quiet without being infected. The immune response makes things worse: the support cells release inflammatory signals as they fight off the virus, and those signals can further disrupt the neurons through a kind of collateral damage. This explains why smell loss from COVID can hit suddenly and completely, sometimes as the very first symptom, before cough or fever appear. COVID patients are 27 times more likely to lose their sense of smell than patients without COVID, making it one of the most distinctive features of the infection.
The good news in this mechanism is that the support cells regenerate. Once a new batch of support cells matures and resumes its job, the sensory neurons typically recover. But that regeneration process isn’t always clean, which is why some people go through a phase of distorted smell before returning to normal.
How Common Smell Changes Are Now
During the first two years of the pandemic, smell and taste problems affected an enormous share of COVID patients. With the original strain and early variants like Delta, somewhere between 44% and 72% of infected people reported some degree of smell dysfunction. That number dropped substantially with Omicron and its subvariants, falling to roughly 13% to 18% of patients. The virus likely evolved in ways that shifted where it replicates most actively, affecting the nasal lining less aggressively than earlier strains did.
Still, with hundreds of millions of infections worldwide, even a lower percentage translates to a large number of people dealing with smell problems at any given time.
How Long Smell Problems Last
Most people recover their sense of smell within a few months. About 74% recover within 30 days, roughly 86% within 60 days, and 90% within three months. By six months, about 96% of people have their smell back.
That leaves a meaningful minority, estimated around 5.6%, who may develop persistent smell dysfunction that doesn’t fully resolve on its own timeline. For these people, the distortion phase (parosmia) often feels worse than the total loss phase. Losing smell entirely is disorienting, but smelling everything as burnt or rotten can affect appetite, enjoyment of food, and emotional well-being in ways that are harder to adapt to.
Smell Retraining Therapy
The most widely recommended approach for recovering smell after COVID is olfactory training, a structured daily practice of deliberately sniffing specific scents. The protocol is simple. You expose yourself to one scent from each of four categories, twice a day, typically morning and evening:
- Flowery: lavender
- Fruity: lemon
- Spicy: clove
- Resinous: eucalyptus
Essential oils work well for this because they provide a consistent, concentrated scent. You hold each one close to your nose and sniff gently for about 15 to 20 seconds, actively trying to recall what the scent should smell like. The idea is to retrain the connection between your nose and your brain by giving the regenerating neurons repeated, predictable input.
This isn’t a quick fix. Most protocols recommend continuing for at least three to four months. Progress can be slow and nonlinear. You might notice one category improving while others stay flat, or you might have days where everything smells worse before it gets better. The distortion phase, where things smell wrong rather than absent, is often a sign that the neurons are reconnecting, even though it doesn’t feel like progress.
What the Distortion Phase Feels Like
If you’re in the parosmia phase, certain triggers tend to be especially problematic. Cooked meat, coffee, onions, garlic, and eggs are among the most commonly reported foods that smell or taste off. Many people describe these foods as having a shared underlying “COVID smell” that’s hard to put into words but falls somewhere between burnt rubber, sewage, and chemicals. It’s consistent enough across patients that researchers believe specific types of odor-detecting neurons are more vulnerable to the damage than others.
Some people find that cold or room-temperature foods are more tolerable than hot ones, since heat releases more volatile compounds that trigger the distorted response. Experimenting with food temperature, seasoning, and texture can make eating less unpleasant during this phase. The distortions do fade for most people, but the timeline varies widely, from weeks to well over a year in some cases.