Mammalian cells produce odor compounds in response to viral infection. Cristina E. Davis and colleagues at the University of California, Davis, USA, discovered that mammalian cells emit a specific set of “smells” upon being infected with influenza viruses. These odors are primarily composed of volatile organic compounds, which can be detected by using gas chromatography/mass spectrometry (GC/MS).
Specifically, circulating B-cells from our immune system are capable of producing chemical odors that appear after viral infection. Most of these compounds are specific to the strain of influenza, and they appear on a distinct time course post-infection. In some cases the researchers were able to detect flu just 6–8 hours after infection. Several of these chemicals appear to be generic influenza biomarkers.
This breakthrough may allow researchers to monitor for flu-associated compounds in exhaled human breath as an asymptomatic measure of viral infection—at a stage earlier than present clinical methods. It also appears that some of the compounds detected may be strain-specific, which could allow for further identification of the new infection.
- Cellular Scent of Influenza Virus Infection,
A. A. Aksenov, C. E. Sandrock, W. Zhao, S. Sankaran, M. Schivo, R. Harper, C. J. Cardona, Z. Xing, C. E. Davis,
ChemBioChem 2014.
https://doi.org/10.1002/cbic.201300695
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I was always curious about this. As every time I have a viral infection and as it gets better I would keep getting a peculiar distinct odour for myself through my breath or sweat or I don’t know from where .. and there have been different odors each time dome times some repeated. At times it was like vegetables rotting or like algae or fungus . During covid it was more like strong odor of pulses being cooked . After covid it was mostly like strong garlic and onion or occasionally like the gutter or like urine or stool. Whatever it was each time they left me so nauseated
At first, I thought Chick-Fil-A changed their ingredient in the batter. Then the odor become more distinctive when I noticed it was appearing after inhaling or exhaling after any food. Acidic food made it more noticeable. To me, it was almost as if I took a swig of acetone and metalloid together and it was repulsive. It me very very nauseous. I currently have the flu and I initially thought the odor was a side effect of the medication (Oseltamivir and Ibuprofen) however, I mentioned it happened at other times as well.
Oh my god I am eating Chick-fil-A a noticed it too! I started to get better and thought what the heck I’ll finally treat myself to a meal. Wow
My husband releases a foul smell every time he is sick. I think he sweats it out. Our whole bedroom reeks and I can’t stand to go in there. He currently has Influenza A… and I do too actually, but I am staying in a spare bedroom because I can’t stand that smell!
I have influenza A and my daughter says I smell like breakfast/maple sausages!
How long does this smell last and what can I do to get rid of it
I always notice a distinct odor in my sweat whenever I have a fever. It doesn’t smell like normal B.O. but more like an almost alkaline/ammonia smell mixed with B.O. Kind of like old urine. It permeates everything like clothing and bedding and is disgusting. I literally have to change my bedding everyday when I am sick.
I currently have influenza A and my husband says I smell like soup- like chicken noodle soup or chicken ramen…it doesn’t matter how often I shower or scrub, I smell like soap and chicken soup.
I am currently sick with flu and I am experiencing smelly palms. No matter how many times I wash my hands, they smell like a sweet dirty sock. I had Covid 2 years ago an experienced a similar smell. This resulting smell now helps me identify if I am sick with a virus. Thanks for the explanation of why this odor occurs when I am infected with a virus.
I currently have influenza B and I have the most nastiest smell in my nose like acetone like a nail polish remover. It’s the worst smell.
Im currently suffering with flu and when I blow my nose the smell is unreal. It’s like rotting veg smell. Really dirty
I’ve been sick for almost a week & I smell like maple-flavored breakfast sausage. Idk if I have covid or what.
I currently have the flu (going on day 4) and wake up multiple times during the night drenched in sweat. And I don’t even know how to describe the smell. It’s a very weird smell. Reminds me of that “hospital smell”. Can’t wait to get over this.
I’m on day 4 of the flu and my fever finally broke. My wife said the entire back half of the house smelled like the meat sweats while I was in bed fighting the fever. The whole bed was smelly and disgusting. I am currently washing everything in hopes of getting rid of that foul odor. Ugh.
Jessica,
That’s a great description of the smell. “hospital smell”. It’s terrible. I’ll be so glad to be healthy again. I wish the same for you!
I have the flu now for the second time within the month. The first time it was like all I could smell was mold everywhere, really musty. And the taste in my mouth was really metallic and salty, like freakishly salty. Now, again, this second time, same exact thing. So weird.
I am getting over influenza A and I still have a lot of thick nasal drainage. There’s a strange ammonia like smell in my nostrils. I wasn’t sure if it had anything to do with the flu but after reading some of the comments it seems that this is likely a symptom of the flu.
I think i had a terrible influenza for a week now, and started with migraines for few days after painkillers and paracetamol it started to breakdown but also breaking down my bones, had terrible bond ache, and since yesterday I’m experiencing a combination of acetone and ammonia like smell in many food, specially acidic food and the smell is crazy when it comes to vinegar
I had a very high fever a couple days ago and yesterday my sweat was so gross smelling. I had almost pure liquid diarrhea the whole day after the fever and my sweat smelled like wet dog and the sweat that came the day after was rank and I have no descriptor for that smell. I had eaten some bad meat the day the fever hit me. The fever was bad enough to make me delirious. Very weird.
I just got over something feeling like allergies/flu. Had bad headache, itchy throat , fever for a day and body aches. Now my underarm BO is intense. Everything smells bad to me. All I can do to feel better is to stay hydrated.
I had flu or cov19 8 days now I’m getting smelly fish
Same! I thought people would think I was crazy, but I was out of my mind for a little bit. My temp peaked at 103.5. And I thought for sure I was literally going insane. Then my dumb a**, took a really hot bath (normal bath water felt too cold for me) When I got out, I lost my hearing, my arms were limp and there was a tightening in my jaw. I was about to pass out and puke at the same time. I just fell down and laid there. I don’t know what this is, that’s going around. But man is it brutal!
When I had COVID & right now with me having the flu, I smell and kind of taste like a sweet meat type smell…
When I had COVID a ate meatloaf, and store bought box pumpkin spice pancakes… And having the flu right now, I am smelling the memory of that or the smell that I smelled when I had COVID. Anyone else have that vibe of a smell with COVID/flu?
My kids and I are sick with virus similar to influenza A, haven’t been tested yet. I woke up sweating bad a few nights in a row and smelled like mildew. I’m glad I got on here and saw that it is a real thing. Thanks for info everyone!
I have COPD. Got some sort of fast acting flu type symptoms with 103° temp. Went to ER on second day and they tested for COVID and Influenza, both Negative. Was released same day with treatments and meds, with no improvements. By day 4 was down to about 1% lung capacity and was back in ER. Was released that night after a few treatments and meds. Was feeling slightly better, fever finally broke. Was awoken three different times with torrential sweats soaking everything. On the last time I noticed a smell I can only describe as smelling a baby bottle that had milk in it a couple days ago and haven’t been washed yet, but the taste was that plus add what I assume is dirty month old dishwater. It is day 5 and I found this during my research. 01/31/25. I will update if I experience anything else useful.
My daughter called me to ask me a crazy question regarding her flu. It was exactly about this. I have had the same pungent skunk like aroma as well with my flu. . It sends out a big warning sign for others to stay away from you. It jarred a memory of of my father’s bout with the flu in the 70s. He stunk as well and my mother’s obsession became trying to eradicate the door.
Yep. I have the flu right now. Night sweats absolutely drenching me, and it smells like cat pee. I thought for while the cat peed in the bed with me