Lost sense of smell may be peculiar clue to coronavirus infection | Hacker News Reader

Lost sense of smell may be peculiar clue to coronavirus infection

nytimes.com

131 pointsbaxtr59 comments

Rudy Gobert, the guy in the NBA who was first to test positive and did the whole touch the microphone things at one of his interviews before the test even, came out about his lack of smell and taste. I was thinking his name could be brought up in that article considering his famousness of patient 0 in the US sports world.

Hopefully this doesn't give people more fear in thinking about their own symptoms, but on the other hand, seeing an odd possibly symptom can really help make them take it more seriously overall.

https://www.reddit.com/r/nba/comments/fn6kh0/rudy_gobert_giv...

A few days ago my mother mentioned that she had gone buy groceries, stopped before a florist, and tried to smell some lavender, but for some reason could not feel absolutely anything, which she found interesting, as it has a relatively strong smell and she didn't have a cold. Looking back, none of us felt particularly great around that week, so I wouldn't be surprised if that had been covid-19. I guess looking back it makes more sense. It seems a lot of people go through it barely having any symptoms.

I've also heard that 93% of people who think they have Covid-19 are wrong.

You've heard nothing and have no data, because we don't have any Covid-19 antibody tests, so we have no clue who has had and recovered from the disease, unless they were tested while contagious.

Not to support a dataless claim...but...isn't the fact that ~90% of tests come back negative (and tests are hard to get) indicative of their point that the vast majority of people who think they have the disease, do not? AFAIK the testing is not random at this time.

https://covidtracking.com/data/

there is a ~30% chance you can still have it even with a negative test though

No, because by the time they get around to testing you, you could be completely devoid of the virus, or it could be only in your lungs, or the test just fails for whatever reason.

The 93% I last saw is in flux and will continue to go down as flu and colds abate in the northern hemisphere and real coronavirus cases increase. This also doesn't include people who could not get tested because their symptoms were mild, even though they thought they had it.

> This also doesn't include people who could not get tested because their symptoms were mild

My partner and I are in that boat (in the NYC area). We had a full week of mild Covid-19 symptoms (I still do not recommend); initially, we couldn't get tested because our fevers weren't high enough and we had no known exposure. By the time we established a known exposure (one of my colleagues got a test while hospitalized with pneumonia, it took a week to come back positive) our symptoms had mostly abated and they would only test sick people. So we'll never know if we had it, but have to both a) continue to isolate (for a variable amount of time, depending on who you ask) under the assumption that we're contagious and b) continue to assume we're still at risk of acquiring it.

Strangely, the only symptom I have left is an oscillating sinus headache and anosmia. Fortunately, some testing I did with vanilla extract this morning indicates that my sense of smell might be healing slowly, instead of somehow permanently damaged.

The last numbers for tests in NY is 28% positive, and apparently suggesting and infection rate of 1 in 700.

Well if you think you might have the disease but you're asymptomatic you might not get the test.

I wouldn't go to such a precise number, but you are right that the majority do not end up testing positive. The test quantities are limited, so they try to select candidates that are likely to have it. Even among these, the rate of positive tests seems to have ranged from ~5% up to ~20%.

Know some family members with it their all near non-working capacity some of them bedridden if you got it you know you got it there's no question it it puts you in bed unable to walk.

It's widely reported to be asymptomatic for many. Iceland did random testing and I think half the positives had, and developed, no symptoms at all.

Edit...should have cited a source:

"Early results from deCode Genetics indicate that a low proportion of the general population has contracted the virus and that about half of those who tested positive are non-symptomatic,” said Guðnason. “The other half displays very moderate cold-like symptoms."

https://www.buzzfeed.com/albertonardelli/coronavirus-testing... (Yes, I know, BuzzFeed...but it's a direct quote, not their interpretation)

It's certainly an interesting characteristic. If the person is asymptomatic then they spead the contagion, it continues to be effectively undetected. Then it finally strikes. And so on. In theory this aided the original spread. By the time say there were 100 cases showing symptoms, there were actually plenty more roaming around. By the time enough detectable cases were racked up, it was already too late. The numbers favored the virus.

Anyone know how common this is in viruses?

It is not unusual. Cases in point: HPV, herpes virus.

> Anyone know how common this is in viruses?

It is the norm. It's not just a matter of being common; diseases face strong selective pressure against virulence by the exact mechanism you describe -- virulent diseases inhibit their own spread by disabling their hosts.

I've found this:

https://www.covid.is/data

The private company did there the randomized tests (deCode). But I don't know where the support for your claim ("half the positives no symptoms") can be found.

Edit: thanks for source, note however, in your statement "had, and developed, no symptoms at all" the part "and developed" doesn't necessary follow from the original quote and what we know about the test -- apparently it is already known that it can take up to 14 days before the symptoms develop, and checking, the said tests are the orange stacks in the bars on the page I've linked -- the tests are too recent to know that.

I updated with a source.

Just because asymptomatic folks are testing positive doesn't mean they stay asymptomatic.

My understanding is this is just a temporary phase of the infection where most people are asymptomatic while spreading the virus. Eventually, without treatment, it usually escalates to a symptomatic phase.

From the source I linked to:

"The population was tested again after a two-week lockdown and isolation. Researchers found that transmission was reduced by 90% and all those still positive were without symptoms and could remain quarantined."

Did you even read the article?

"in South Korea, where testing has been widespread, 30 percent of 2,000 patients who tested positive experienced anosmia as their major presenting symptom"

and:

"mounting anecdotal evidence indicates that lost or reduced sense of smell and loss of taste are significant symptoms associated with Covid-19, and that they have been seen in patients who ultimately tested positive with no other symptoms."

> It seems a lot of people go through it barely having any symptoms.

That's also what makes it so dangerous. During the early outbreaks people were constantly joking about how people with COVID-19 felt up to taking intercontinental flights, going to megachurch services, going to the gym, visiting Disneyland....

Compare to Ebola, which is pretty awful, but if you get sick with Ebola you're not going to transmit it very much because you're going to feel absolutely miserable and there's a really good chance you'll die soon. Which sucks and I'm grateful that the world managed to stop the various Ebola outbreaks we've seen, but if you want a real pandemic, you want something with a nice long incubation period that presents asymptomatically to enough people that it can really spread around a lot. And that's what we have here.

>That's also what makes it so dangerous. During the early outbreaks people were constantly joking about how people with COVID-19 felt up to taking intercontinental flights, going to megachurch services, going to the gym, visiting Disneyland

What if the virus caused this? raise the threshold for people to feel anything, so they go out and spread it while seeking sensation?

That would be right up there with toxoplasmosis. It's entirely plausible, too.

Anecdote: I've had anosmia for exactly a week now, without any nasal blockage or any other symptoms of covid-19. It seems to be slowly getting better as of today (I can smell cologne, a bit). My doctor's office said they wouldn't test me, but that I should assume I'm infected and stay at home.

Location?

Seattle

Some good comments on another article: https://news.ycombinator.com/item?id=22648580

“This seems like a potentially game-changing discovery - if we could trivially diagnose 30%+ of cases, that could drastically diminish growth rate.”. I agree, especially if the symptom shows up early.

"Rapid Clinical Evaluation of Anosmia - The Alcohol Sniff Test" - see https://news.ycombinator.com/item?id=22650256

Google Trends shows trending before the Anosmia articles AFAIK):

https://trends.google.com/trends/explore?date=now%207-d&q=%2...

https://trends.google.com/trends/explore?date=today%203-m&ge...

“I lost my sense of smell when I took a zinc tablet to prevent covid-19 (serious but funny). Maybe I shouldn't have dissolved it in my throat (as was suggested).”. Another comment mentioned Zinc in high doses can cause Anosmia.

Lots of good anecdata from people that have lost se se of smell/taste.

“ Post-viral anosmia is one of the leading causes of loss of sense of smell in adults, accounting for up to 40% cases of anosmia. ”.

I tried searching for how common this is a symptom for flus/colds. It appears to be rare, but if anyone can find some hard data that would be grand.

What I'd like to know is, what percent of people with Covid 19 can smell and what percent can't? That would tell us if it is a good discriminator.

In an ideal world, everyone who had Covid would not be able to smell, and then we could justify doing a second, more reliable test on them. Anyone would could smell would be ok.

30% in South Korea.

That's only the ones without additional symptoms or mild additional symptoms.

In an ideal world we'd have infinite tests (that take 0 seconds to get results) and not need to rely on symptoms that may present differently, or may not even present in some patients. We'd be able to test everyone daily, multiple times, for the virus (nose/throat swab), and for antibodies (blood), and have a system setup for contact tracing. We'd find a way to do that that doesn't infringe on our peace-time civil liberties.

We don't live in an ideal world, unfortunately. In the absence of a Covid-19 test, we could test for the flu, because knowing I have the ordinary flu, or not, vs Covid-19, is still valuable information, especially in places where there is still no ban against large gatherings.

With a few order of magnitudes more testing, whatever the disease, we could go about our normal lives with only slight modifications, rather than this upheaval we're currently undergoing.

Are you sure that you're less likely to have Covid-19 if you have the flu?

For some people I think this is just a normal response to respiratory viruses. My ex would swear she lost her sense of smell (and taste) whenever she had a cold.

This is not something I can recall experiencing, though. If anything, my sense of smell seems enhanced when I'm sick. Strong smells often seem more intense and make me feel worse, even smells that normally wouldn't bother me much.

The "common cold" virus is also a coronavirus, so that makes sense. That would still help in differentiating if you have the flu or Covid-19. I only heard of getting more sensitive to smells in connection with migraine (totally anecdotal evidence)...

Rhinovirus is another well known cause for a common cold. A quick search result: webmd [1] gives 10%-40% for rhinovirus, 20% for coronavirus. CDC [2] has rhinovirus as the most common cause, and adds: “ Other viruses that can cause colds include respiratory syncytial virus, human parainfluenza viruses, adenovirus, human coronaviruses, and human metapneumovirus.”

[1] https://www.webmd.com/cold-and-flu/cold-guide/common_cold_ca...

[2] https://www.cdc.gov/features/rhinoviruses/index.html

In fact some "common cold" coronaviruses are really quite similar to SARS-ncov-2.

hcov-NL63's protein spike, for example, binds to the same ACE2 receptor, and is also believed to be a polymorphism of bat and civet coronaviruses. It's also known to cause pneumonia in immunocompromised patients.

But of course, a big difference is that hcov-NL63 has probably been circulating in humans for centuries, so we tend to acquire immunity to it by being exposed as children.

Loss of sense of smell isn't uncommon for cold or flue. Oddly it may depend on what you've got in a way I can't explain. I remember utterly losing smell, then starting to recover it in a pub just before closing time when one of the bar staff was splashing brasso (https://en.wikipedia.org/wiki/Brasso) around to clean the taps. I literally could no smell a thing beforehand. Yet I've had cold/flus where that didn't happen. It would be interesting to know why one coronavir does and another doesn't.

FYI loss of smell is known to be an early symptoms of parkinsons IIRC.

if you have turbinates in your sinuses, and they inflame when sick/allergic, it can reach a tipping point where you can't smell any more. So one flu may inflame them more than another, or you have have grown more/larger turbinates later in life where you more easily lose your sense of smell.

perhaps covid-19 cause the loss via some other mechanism entirely, I have no idea.

Interesting, I've never come across the term.

https://en.wikipedia.org/wiki/Turbinate

FYI for others. Thanks for that

Is it me or is this discovery an incredible stroke of luck for the prospects of stopping this damned thing? Might this help otherwise asymptomatic people self-diagnose and take proactive quarantine measures? And these measures would help drop the R-naught.

Does not look like sensitivity or specificity of anosmia is good enough by itself as a diagnostic criterion.

The specificity is high enough, certainly better than for having a cough, to tell everyone with anosmia to self-quarantine. I agree that sensitivity is not great.

For people who are asymptomatic, how long before it's completely purged from the body?

I ask because there is a lot of "asymptomatic people may not remain asymptomatic" type of discussion whenever a thread on this coronavirus comes up.

Anywhere from 14 to 37 days, based on this article https://www.mcknights.com/news/coronavirus-may-live-in-patie... which references this study: https://www.thelancet.com/journals/lancet/article/PIIS0140-6... (scroll to heading "Findings").