Every time I get a cold or flu, I always get this weird smell when I breathe in through my nose. Does this happen to anyone else, and what causes this?
You mean that metallic kinda smell? Dunno, but I’d love to hear from somebody who does.
I’m interested too.
I thought that metalic smell had to do with sinus infection.
I’m thinking it’s the smell of mucous… Does someone have a better hypothosis?
Who the heck can actually smell anything with a head full of snot? It always struck me as more of a sensation of smell than anything I was really smelling. If that distinction makes any sense…
I think it’s the smell of diseased, pussy snot. Lots of dead leukocytes and stuff.
jb
nitpick: Colds and influenza are viral infections. Pus formation (main component-dead neutrophils) occurs in bacterial infections.
I’m not sure whether there’s a huge cellular influx into the inflamed nasal mucosa. If there were inflammatory cells there, though, they’d more likely be lymphocytes and monocytes.
As to the OP: I’ve noticed a distinct odor as well. I attribute it to either:
-
a non-cellular component that is extravasated or produced locally in response to inflammation and can tickle the olfactory receptors
-
changes in the environment of the olfactory receptors secondary to inflammation (eg. different ionic consistency or pH of inflamed tissue) that induce “false signals” from the olfactory receptors. These are interpreted by the brain as a smell
what becomes of the lysed cells in a viral infection? do they get turned into something like pus, or not at all?
could you be, by some chance, actually smelling the viral particles?
jb
Probably not at all. The most important cells in combatting a viral infection are lymphocytes, T cells and B cells. A subset of T cells (CD8 T cells) directly and specifically kill virus infected cells. During a viral infection, the virus-specific CD8 T cells undergo a dramatic expansion (in experimental viral infections in the mouse they can come to represent 20% of the total pool of CD8 T cells, while prior to infection, they are difficult if not impossible to detect). They can concentrate in the infected tissue but are also found at body sites remote from the infection. With resolution of the infection, the number of virus-specific CD8 T cells diminishes rapidly. But they don’t form pus. Instead, they die by a process termed programmed cells death (apoptosis). Basically this is cellular suicide. It happens when a cell realizes it is no longer of any use to the host (Such nobility!. Cells that die by programmed cells death are rapidly gobbled up by macrophages, the immune system’s sanitation department.
B cells are the antibody producing cells and they can be very important in viral immunity as well. In fact, the way that the influenza vaccine (and many other antiviral vaccines) works is by inducing an antibody response that protects the host from infection from a given influenza strain. Antiviral B cells also expand during an infection or with immunization, but to a much lesser degree than CD8 T cells. In a vigorous response, the anti-viral specific B cells population is probably at most around 0.5% of the total B cells in the host. With resolution of the infection, the majority of these die (by programmed cell death) and are gobbled up by macrophages. An important subset of the original antiviral B cells persists to become memory B cells/plasma cells. These can continue to secrete anti-viral antibody for a long time (years) giving the host long-lasting immunity.
Usually odorants are small volatile molecules. That way they can swim through the air into your nose. Smell receptors probably target molecules with such characteristics. Viral particles are large (relative to the typical odorant) and composed of protein and carbohydrate. While I wouldn’t rule out a chance interaction with an olfactory receptor, I think the likelihood would be low.
sweet! thanks choosybeggar.
Remember, beggars can’t be choosy, but choosy beggars choose Jif.
jb
I’ve been bothered by this mystery myself for years, and this old thread lands near
the top of a google search so why not build onto that?
I think choosybeggar was in the right place, the immune response.
A strange and pungent aroma is also my experience, somewhat metallic, but also
a strong note of aldehyde. It seems to be in the mucus, but this year I noticed
something else. It got stronger as the virus waned. As I expectorated the last
of the bronchial crap, the odor was stronger than ever, and made my eyes water a bit.
Then it makes sense to suppose that the compound is human produced.
I would go further to speculate it isn’t merely a byproduct of immune activity such
as cell death or some other kind of metabolism, but an antibiotic substance itself.
As the virus dies away, the battlefield is suffuse with the stuff that killed it, and
the production machinery fully wound up and still running hard just to be sure.
It should also be in the small molecule class, where antivirals like Tamiflu are.
Large molecules would not be so volatile and detectable by the olfactory system.
So that’s my hypothesis, animals produce their own small molecule antivirals, besides
huge molecule MAB-like compounds.
Mental note to self; don’t date any women jb_farley has gone out with.
On topic, I always thought the smell was very much like the smell of an infected wound, so basically pus, or pussy discharge.
I would surmise it may be the smell of zombies myself
Duly noted that the thread is 14 years old … but I do wonder about choosybeggar’s definition of pus. I am not so sure that pus requires bacteria nor that say a cloudy eye discharge full of lymphocytes in response to a viral trigger, or the thick cloudy post nasal drainage in the first several days of a viral URI (which do contain WBCs), do not count as pus, and being cloudy, or green, in the first few days does not mean that there is a bacterial infection. The pus associated with tuberculosis, for example, is predominantly lymphocytic, and no one would debate that it is pus because the WBC are lymphocytes rather than neutrophils.
No idea what causes the metallic smell that some people seem to report though.
BTW the preferred adjective for a discharge full of pus is “purulent” rather than “pussy.”
Why does someone always have to mention zombies when someone resurrects an old thread? So you noticed the thread was old, here’s a medal for you. It’s annoying.
Sorry for the hijack.
Oh, seconded Honey, it’s a tired old joke.
It’s kinda like when someone gets a haircut, EVERYBODY simply MUST notice it out loud.
When I get a haircut, I find it necessary to stay at home and hide in a closet for a week or two, lest the fact be pointed out to me by everybody I encounter. Given that I used to work in a software development environment, it went something like this: (Warning: Technical computer jargon ahead!)
Scene: Standing in hallway chatting with a few programmers. Another programmer joins us.
New programmer, to me: I see you got a new haircut.
Me: No, it’s the same old haircut I always get.
Other programmer: It’s a new instance of an old haircut.
Me: There you go!
Hi guys!! Sorry to jump in so late (lol 16 years better now than never). But if u like me chances are u still worried about the cold back in 2000. Maybe the music has changed since then…no more Britney Spearz lol but HEALTH and HELPING EACH OTHER has not!
Anywho, i ALWAYS carry matcha moringa and chlorella in my backpack. And it helps…i suggest u try. Get a backpack that swings around to the front pls so u can always be ready. You can get MM and C off amazon (couldn’t do that in 2000 lol). Pinch some of both of those in your daily green drink and u be right as rain.
Get well. Mwahhhhhh