
50% – 75% of cases of Covid-19 are asymptomatic - fortran77
https://www.repubblica.it/salute/medicina-e-ricerca/2020/03/16/news/coronavirus_studio_il_50-75_dei_casi_a_vo_sono_asintomatici_e_molto_contagiosi-251474302/?ref=RHPPTP-BH-I251454518-C12-P3-S2.4-T1
======
warabe
I live in Japan and I experience mild symptoms since last Wednesday but not
sure if my symptom is due to Covid-19. In Japan, You have meet two conditions
to take a CPR test.

1\. the symptoms with fever of 37.5 degrees or more continue for 4 days or
more (for the eldery and those with underlying disease, "4 days" becomes "2
days")

2\. you have strong laxity (malaise) or breathlessness (dyspnea), or you have
underlying diseases (diabetes, heart failure, respiratory diseases (such as
chronic obstructive pulmonary disease))

I don't meet the first condition, so I was refused to take a test, but I still
have chest tightness and consistent coughing. I wonder where the number "37.5"
comes from, and 4 squeal days!? If the article in question is true, these two
conditions are totally meaningless.

So why is taking a PCR test so hard in Japan? Most people believe it is due to
Olympic. The Japanese prime minister, Shinzo Abe, still believes we can hold
Olympic as planned at this point. To that end, they want to hide the case of
infection as possible. I feel strong anger towards my government since they
care more about Olympic than human lives.

At this point, Olympic will be inevitably postponed. I hope my government is
smart enough to loosen the conditions and let people to take PCR tests
immediately…

~~~
surfsvammel
I think there is a more reasonable explanation why they are not testing you.
Simply because they wouldn’t do anything with that information anyway. If the
test is positive they’ll send you home to quarantine telling you to call back
if your fever worsens. If the test would show negative, they’d tell you, guess
what; “please call back if your fever worsens, and stay in quarantine anyway”.

So the information doesn’t really matter.

In Sweden once they change tactics from trying to track each and every case,
and who they might have gotten it from etc, to a a strategy more about just
accepting that it’s spreading and trying to limit the spread in general, and
protect the weak. Then they also stopped doing testing here.

Unless you are in a risk group, the test doesn’t really make a difference.

~~~
nodamage
> Unless you are in a risk group, the test doesn’t really make a difference.

If the test is positive, you can self-quarantine _and notify everyone you 've
been in contact with that they need testing_. Then any one of those people
that tests positive can do the same thing, etc. etc.

If you don't do any testing, you end up with a bunch of positive but
asymptomatic carriers wandering around unknowingly infecting other people.

South Korea is taking this approach and they seem to be doing a lot better
than most other countries.

~~~
tim333
Indeed and it probably makes much of the difference why active cases in Korea
have kind of leveled off while in Europe they are growing about 25%/day. And
just a reminder that's 800x a month.

~~~
paul_f
Is it possible for the number of cases counted to go up simply because more
testing is occurring, while the number of people with the virus has leveled
off?

------
nostromo
I wonder if this will be like H1N1.

At first we only identified extreme cases and we had these terrifying reported
fatality rates.

Then we identify more and more mild or asymptomatic cases and the rates drop
and drop.

We’ve already seen how CFR was reported as 3 or 4%. Then on the cruise ship
full of people over 60 it’s 0.7%. If there are lots of mild or asymptomatic
cases it will likely be much lower.

H1N1 was identified as having a scary 0.4% CFR early on and was later found to
be much lower, but we didn’t know until after the fact.

An example report from 2009:

[https://www.who.int/immunization/sage/1.Briand_epi_7th_July_...](https://www.who.int/immunization/sage/1.Briand_epi_7th_July_2009_\(rev_6July_09\).pdf)

In the end it may have killed over half a million people in 2009 - but for
some reason people barely noticed. (Tangent: I wonder if it’s partly the
changing media landscape from 2009 to 2020.)

~~~
easytiger
The WHO predicted that 150 million people would be killed by avian flu

[https://www.google.com/amp/s/amp.theguardian.com/world/2005/...](https://www.google.com/amp/s/amp.theguardian.com/world/2005/sep/30/birdflu.jamessturcke)

Using the same logic that had lead to the severe predictions for cv19.

For swine flu they promoted and stood by a CFR of 60%. Again turned out to be
nonsense; nonsense known at the time to others

[https://jech.bmj.com/content/62/6/555.abstract](https://jech.bmj.com/content/62/6/555.abstract)

~~~
notahacker
Overestimates of the severity of the threat have much less harmful
consequences than underestimates. For a start, actual casualty statistics are
not independent from mitigation actions taken.

~~~
easytiger
> Overestimates of the severity of the threat have much less harmful
> consequences than underestimates.

We didn't take the estimates for SARS and h1n1 as "seriously" as now, and they
are just as if not worse than this.And look what happened.

~~~
notahacker
I think Asian countries took the estimates pretty seriously. I think both
would have been worse if they didn't, especially SARS.

------
confeit
> "The vast majority of people infected with Covid-19, between 50 and 75%, are
> completely asymptomatic but represent a formidable source of contagion".

The Professor of Clinical Immunology of the University of Florence, Sergio
Romagnani

> Asymptomatic infection has been reported, but the majority of the relatively
> rare cases who are asymptomatic on the date of identification/report went on
> to develop disease. The proportion of truly asymptomatic infections is
> unclear but appears to be relatively rare and does not appear to be a major
> driver of transmission.

[https://www.who.int/docs/default-source/coronaviruse/who-
chi...](https://www.who.int/docs/default-source/coronaviruse/who-china-joint-
mission-on-covid-19-final-report.pdf)

> Clinical and epidemiological data from the Chinese CDC and regarding 72,314
> case records (confirmed, suspected, diagnosed, and asymptomatic cases) were
> shared in the Journal of the American Medical Association (JAMA) (February
> 24, 2020), providing an important illustration of the epidemiologic curve of
> the Chinese outbreak. There were 62% confirmed cases, including 1% of cases
> that were asymptomatic, but were laboratory-positive (viral nucleic acid
> test).

[https://www.ncbi.nlm.nih.gov/books/NBK554776/](https://www.ncbi.nlm.nih.gov/books/NBK554776/)

Weird discrepancy on the order of 75x. I'd love to trust the experts, but who?
I am leaning towards truly asymptomatic spread being rare, since you get
infected by SARS-CoV-2, not COVID-19 (COVID-19 is the disease), the level of
uncertainty of 25% is higher than for other reports, and the main reported
mode of transmission is through symptomatic cough droplets.

~~~
endogui
The Italian number (75%) comes from testing everyone in a village of 3000
people. The Chinese number (1%) comes from testing everyone who comes to
hospitals and maybe their family members. I would guess that the Chinese
sample was selected for people displaying symptoms (asymptomatic people will
not go to the clinic), while the Italian number biases for people early in the
course of the disease. For the purposes of public health and controlling
disease spread, the Italian number is more meaningful.

Note also that it is possible the virus has evolved to spread more easily,
which in the context of a lot of screening and social distancing of
symptomatic people would mean more asymptomatic spreading.

~~~
lgats
How are the South Korean's coming up with such few positives if the disease is
presumably spreading among the 70% with no symptoms?

~~~
endogui
Most "asymptomatic" people will show symptoms within two weeks, so aggressive
cluster/contact tracing works. South Korean local goveenment staff are
following the credit card use, transit use, and other daily movements (CCTV
logs) for every confirmed case, then issue two week self-isolation orders to
those who shared a workplace, restaurant, cafe, church, or elevator with the
confirmed case. Since most cases get a short lived fever or cough within two
weeks, SK has been able to stop most transmission chains. I'm actually a bit
confused about the scope of SK testing. It looks like everyone with symptoms
is being tested, as well as quarantined health care workers and quarantined
people from high risk groups, but I'm not sure whether asymptomatic people are
tested at the end of their quarantine period.

~~~
notahacker
Yup. Apparent efficacy of the South Korean approach versus more generalised
'self-isolate if you have symptoms' instructions would be a point in favour of
the disease being often asymptomatic [for extended periods]

------
lend000
I'm not a confirmed case, but I'm a 90% sure case based on symptoms and
symptoms of people I have been in close contact with, and so far the
experience has been relatively mild, in the literal sense. The primary
discomfort has likely been the anxiety of how the tightness in my chest might
progress (which ironically can also cause chest tightness).

I'm in a low risk group. I had lethargy and high fever the first day of
symptoms (a little over a day after high contact exposure to my suspected
source), then no fever (or very mild fever, can't tell because I have no
thermometer), dry eyes, consistent mild chest tightness and occasional cough
for the following two days (to present). The person I believe I contracted it
from is also in a low risk group and had a sore throat and persistent cough
for about 5 days, and is currently asymptomatic. She had been going about her
business thinking it was just a cold for the duration of her symptoms.

Testing is still difficult in my area, and many folks with mild symptoms like
the aforementioned aren't even attempting to get tested, so I suspect the true
numbers are about 10x-50x the reported confirmed cases. This is good in that
it means the death rate is also off by that factor, but bad in that there will
not be enough fear/incentive for the primary carriers (young adults) to adhere
to adequate social distancing. It's an unfortunate externality when an
infectious disease has discriminatory consequences.

~~~
md224
> I suspect the true numbers are about 10x-50x the reported confirmed cases.
> This is good in that it means the death rate is also off by that factor, but
> bad in that there will not be enough fear/incentive for the primary carriers
> (young adults) to adhere to adequate social distancing.

If the death rate is off by 10x-50x, isn't this approaching the death rate of
seasonal influenza, in which case we didn't actually need to adhere to social
distancing in the first place?

~~~
j-pb
That doesn't add up, if it wasn't worse than seasonal influenza, then Italys
hospitals wouldn't be overwhelmed.

~~~
easytiger
Italy did everything wrong.

They basically turned hospitals into covid19 infection parties.

~~~
bsaul
do you have sources for that ? i'm extremely interested in understanding why
italy seems to be suffering that much compared to other countries. If it's
just a matter of being the first, or if it's also something specific to them.

~~~
jaclaz
As a side note - and JFYI - Italy's situation is very nuanced, as you can see
on this map (divided by region):

[http://opendatadpc.maps.arcgis.com/apps/opsdashboard/index.h...](http://opendatadpc.maps.arcgis.com/apps/opsdashboard/index.html#/b0c68bce2cce478eaac82fe38d4138b1)

In the North (and particularly in Lombardy) the situation is dramatic, in the
center and in the south it is not (yet) that bad.

Basically the lock-down (started on national level on the 10 th of March)
seemingly - and for the moment - managed to work to reduce the spread of the
infection in other regions.

The previous lock-down (limited to some cities/provinces of the north) was
only a couple days before and evidently too late to be effective.

------
surfsvammel
I have shortness of breath, cannot go up the stairs in our house without
having to stop and rest. 37 years old and otherwise quite healthy. Have
underlying autoimmune disease, and am on immunomod. Coughing and light fever.
I’ve had this for 5 days. When I called the hospital they told me to come in
and get tested, but when I came to the hospital they did not test me.

The doctor told me, it wouldn’t make a difference anyway. No matter what the
test would show he would tell me the same thing: go home, isolate yourself,
and come back if your fever worsens.

Once your area reach a certain number of persons affected, there is little use
to try to track each one. When they have changed to a strategy of trying to
protect the weak, and just slow down the spread. Testing doesn’t really add
much value or information.

~~~
wirrbel
I hope you get better soon.

I think your comment describes very well the economics of the pandemic when it
spreads further. Basically you can treat everyone with Corona-like symptoms
like a corona patient. It doesn't make much difference anymore. Isolation and
monitoring of the condition.

If it's a severe common cold the advice isn't that much off, too.

------
GreaterFool
I keep hearing “masks are useless”. If every person who has any cough or any
chest tightness or any sore throat, however mild, put on a mask, wouldn’t that
stop the spread?

I live in Japan. It started here earlier but didn’t explode. Nothing is
closed. Business as usual. _everyone_ wears masks.

Most cases in Hokkaido. Maybe because it is much colder there and easy to
overexposed and tax the immune system.

~~~
kevingadd
I think some of the logic behind "masks are useless" is that if people believe
masks will prevent it, they'll get too reckless about going out as long as
they have a mask. Sadly many people wear masks incorrectly and other people
will wear masks that don't actually block viral particulates while out there
acting more dangerously than otherwise, spreading disease.

IIRC anything below N95 isn't going to do much, and from experience (yay
wildfires) I can say wearing N95s is _very uncomfortable_. Incidentally even
physicians wearing proper PPE (n95 or better, etc) can still catch COVID, so
it wouldn't be appropriate to say that those are good enough.

It's certainly better than nothing - I'd prefer it if everyone out and about
was wearing masks - but the risk of false security leading to dangerous
behavior is strong, and we already have issues with mask supplies, so it makes
sense to discourage it.

~~~
krzat
That's very convoluted reasoning. I think the main goal of surgical masks for
entire population would be to limit amount of virus floating in the air. They
are also good at stopping people from touching their faces.

IMO the goverments should make masks mandatory, even if it's DYI mask made
from few layers of tshirt. And start teaching people how to use them and why.

~~~
kevingadd
If the supply was there I'd absolutely agree. At least in the US it's very
hard to get adequate masks right now (this is partly due to a failure to
maintain supply, there were some news stories recently about how a local
manufacturer was begging the government to invest in this so he could maintain
production)

------
bronzeage
If a virus takes a week to develop symptoms, and doubles every 3.5 days,
that's exactly what do you would expect: after a week 3/4 of the cases are new
and too early to detect symptoms.

asymptomatic proportion sampled at a moment grows exponentially with
incubation period, it means nothing about who will eventually develop
symptoms.

------
jader201
In case this thread doesn’t gain momentum, some more (potentially interesting)
discussion on Reddit [1].

Particularly this post [2]:

> I wonder if they plan to follow up and monitor... From the Diamond Princess
> they initially found 50% of people had no symptoms. However upon following
> them over the course of weeks that dropped down to about 18%. Due to the
> long incubation period it can take some time to determine if someone is
> truly asymptomatic or just not symptomatic yet.

[1]
[https://www.reddit.com/r/Coronavirus/comments/fjuj24/5075_of...](https://www.reddit.com/r/Coronavirus/comments/fjuj24/5075_of_covid19_cases_are_completely_asymptomatic/)

[2]
[https://www.reddit.com/r/Coronavirus/comments/fjuj24/comment...](https://www.reddit.com/r/Coronavirus/comments/fjuj24/comment/fkpkiac)

~~~
IIAOPSW
On an unrelated note, I just noticed this entire time I've been reading
"asymptomatic" as "asymptotic". I thought it was cases that happen in the
limit as severity goes to zero.

~~~
taneq
Some news services have referred to asymptotic spread but it's just hyperbole.

~~~
lurquer
Your obtuse reply isn't even tangentially related to the line of discussion.

~~~
taneq
I feel it's unfair that people have disrespected the trifecta you achieved
here.

------
username90
"Everyone we found to have Covid-19 had serious symptoms, so we don't want to
waste money testing you if you don't!"

I feel this is a trillion dollar mistake, testing more aggressively like South
Korea means that you don't have to deploy the army and quarantine people. I
had mild symptoms and they refused to test me, what am I to do? Self
quarantine without a notice and hence without pay? I could work from home, but
most can't so they will just go to work as normal and spread it. And now it is
all over the world so only drastic measures will help.

~~~
ncallaway
I'm not sure if you're quoting something or paraphrasing a position you
disagree with.

If it's a paraphrase, I'm not so sure it's a fair one.

In the United States, for example, we are urging people not to be tested
unless they have severe symptoms. The reason for that is _not_ to save money,
but it's for a lack of testing capacity. As a policy we would much _prefer_ to
be testing even the mild suspected cases. But we don't (currently) have the
testing capacity to do so.

So I think the lack of testing of mild cases (at least in the United States,
and I suspect in other countries) is more a reflection of our rationing
priorities than it is a reflection of our spending priorities.

If the testing capacity becomes unconstrained and we (or other countries)
_still_ fail to test mild cases.

~~~
encoderer
The lack of testing capacity was a choice.

~~~
ncallaway
Yes, absolutely. The lack of testing capacity was a total failure of the
government.

After the acute phase of the crisis, we should investigate what happened in
great detail.

But the advice about _who_ should get a test is based on the testing capacity
we have now. If we _hadn 't_ failed at testing capacity, we would be
recommending more users get tested.

So, if the critique is: "we failed to produce adequate testing capacity", then
I absolutely agree. If the critique is instead: "The recommendation of who
gets a test is bad", then I disagree. The recommendation is correct given the
test capacity failing.

The solution is not to recommend everyone gets tests, because they can't!
Those tests are being rationed. The solution is to rapidly improve out testing
capacity.

------
Mountain_Skies
Asymptomatic for the entire duration of infection? That sounds bad for
reducing R but good for the health of the individual.

~~~
mkagenius
I would assume that asymptomatic person has a lesser concentration of virus
and hence would be less contagious than the really sick ones

~~~
kalleboo
If you're asymptomatic, you're not coughing droplets everywhere, which ought
to make you less contagious

~~~
tomp
On the other hand, some people (e.g. myself) keep sneezing and coughing the
whole winter every winter, so I definitely wouldn’t consider those _symptoms_
without either headache, body ache, throat pain or fever...

------
xenonite
The original source of the linked article is a letter by Prof. Sergio
Romagnani, sent to the newspaper Corriere Fiorentino, published here on March
15:

[https://corrierefiorentino.corriere.it/firenze/notizie/crona...](https://corrierefiorentino.corriere.it/firenze/notizie/cronaca/20_marzo_15/dobbiamo-
cambiare-rotta-ef23a500-669a-11ea-a40a-86d505f82a96.shtml)

As follow-up, they interviewed him, published on March 17:

[https://corrierefiorentino.corriere.it/firenze/notizie/crona...](https://corrierefiorentino.corriere.it/firenze/notizie/cronaca/20_marzo_17/tamponi-
tutti-bivio-adesso-cominciamo-ospedali-
edb36ab4-682c-11ea-8372-e06aa5c607e8.shtml)

~~~
chimprich
Very interesting, thanks.

Translation of the follow-up article:
[https://translate.google.com/translate?hl=&sl=it&tl=en&u=htt...](https://translate.google.com/translate?hl=&sl=it&tl=en&u=https%3A%2F%2Fcorrierefiorentino.corriere.it%2Ffirenze%2Fnotizie%2Fcronaca%2F20_marzo_17%2Ftamponi-
tutti-bivio-adesso-cominciamo-ospedali-
edb36ab4-682c-11ea-8372-e06aa5c607e8.shtml)

------
xupybd
That sounds like the perfect way for a disease to spread. Do nothing to most.

~~~
abiogenesis
The best evolutionary strategy for a virus is to not cause any disease at all.

~~~
lovecg
Better still, it would make the host feel unusually social.

~~~
thinkingemote
There is a paper that showed that the flu virus makes people more socialable.

It was done with students who took flu vaccine. They found people socialised
more after they had the vaccine (and thus, were a little bit infected)
compared to before.

A literature review looked at the study and came up with the negative
explanation - that people felt more secure or relaxed after getting the
vaccine as they felt safer. Or were more nervous about needles before.

Ancedote:

I think I have covid-19 and the days before symptoms I felt unusually anxious
to get outside and amongst fellow humans. I'm usually an introvert and stay
inside mostly so it was notable.

Suggestion:

Online interview people with symptoms now to collect data on peoples behaviour
in the days before symptoms showed, when they were infected but not showing,
compared to 2 weeks before.

~~~
rabidrat
A vaccine does not make people "a little bit infected". Vaccines are
deactivated virii, so your body develops the antibodies, without any actual
infection.

~~~
Gibbon1
That's not totally true the live Polio Vaccine used a live weak infectious
virus. Which had the advantage of conferring immunity to unvaccinated people.
At the expense of very rarely reverting and causing full blown disease. Far as
I know it's no longer being used because of that.

------
gioscarab
Guys, don't underestimate this pandemic, wear plastic gloves, FFP3 masks and
if possible protective glasses when you are going outside. Leave your shoes
out of the door and wash frequently your hands.

------
robocat
Yet another full population study estimates: “We estimated the asymptomatic
proportion at 17.9%” -
[https://www.medrxiv.org/content/10.1101/2020.02.20.20025866v...](https://www.medrxiv.org/content/10.1101/2020.02.20.20025866v2)

~~~
adam-a
I read this study and the recorded figure is around 50%. They're using some
probability estimation based on the 50% discovered cases to account for people
who had mild symptoms but not at the time they were tested (potentially after
they left the ship). They identify flaws in the study though: the passengers
were mostly old, so they are more likely to be symptomatic. They also didn't
test everyone on the boat, only vulnerable, or symptomatic people, so their
base numbers are missing some number of asymptomatic cases. It's not a perfect
study and I think you could take 19% as a low bound on the figure and in wider
society 50% is plausible.

------
vannevar
It's a largely academic question, at least in terms of mortality and
treatment. If you're asymptomatic, you're unlikely to get tested, and you'll
never even know you had it. On the other hand, if you have enough symptoms to
be tested, you have a higher mortality risk than asymptomatic cases by
definition, so the overall mortality rate doesn't matter to you anyway.

Where it _does_ matter (a lot) is in containment, where we should assume many
more people are contagious than the reported cases, so the average individual
risk of catching it is much higher.

------
andrewseanryan
This article on hacker news a couple of days ago could explain a lot of this.
There is a possibility that a very large number of the asymptomatic positive
tests are in fact false-positives. This could be good news for the world, but
I'm not betting on that yet.
[https://www.ncbi.nlm.nih.gov/pubmed/32133832](https://www.ncbi.nlm.nih.gov/pubmed/32133832).

~~~
postalrat
Wouldn't it be great news if so many are asymptomatic or mild? It might
explain why China seems to have so few current cases given its population.
Maybe many people have already caught it and now have some form of immunity.

~~~
andrewseanryan
I suppose you have a point there. I was thinking that it could be bad that so
many are spreading without knowing it.

Also, if many are asymptomatic, and the test is creating a large number of
false-positives for those that are asymptomatic, there is a chance that this
crisis is not as big as we think it is. Let's hope...

------
PhaedrusV
Occam's Razor would imply that the "asymptomatic non-transmissive" cases are
really just false positives. The only work I've seen on false positives is
these guys, who estimate the FP rate for the active nucleic acid test
screening at 75% chance of there being a 'false positive rate' greater than
47%.

[https://pubmed.ncbi.nlm.nih.gov/32133832/?fbclid=IwAR3LHLplR...](https://pubmed.ncbi.nlm.nih.gov/32133832/?fbclid=IwAR3LHLplRtmPZED3jt_Hjf2ZKysmDcXMU5LgVgNPcqNAtb9EzcQBKMtCIoI)

------
jopsen
Interesting, but it doesn't change the fact that health systems are
overwhelmed.

If the rate of hospitalization is 15-10%, lockdowns seems the only realistic
option.

------
DeonPenny
We've known this for a while. Everyone will get it. You might have it now.
Nothing will happen. Still, quarantine for a while because you'll give it to
an older person or kid. This isn't about a 20-something year old getting sick.
Let your anti-bodies make yourself non-contagious. We are all kindergartens
and this is chickenpox basically.

~~~
grey-area
That means 1-2 million deaths in the US according to the latest modelling from
Imperial Collage London, so it’s likely all countries will proceed to full
lockdown for months at some point soon.

~~~
kart23
This just isnt true. Look at china. Their new cases per day have now dropped
to effectively zero. Under 100,000 people got it, and deaths are around 6,000.
Keep in mind this is for a population of 1.3 Billion. US population is 300
million. Please explain how 2 million people are gonna die in this country.

~~~
grey-area
The paper explains how, these are not my figures but they do seem credible,
this is the modelling team advising the uk gov and the gov has adjusted their
strategy to suppression in response (the tactic in China), but the economic
impact of that is pretty dire too, and it means tough choices.

The measures in China were draconian and long lasting (large cities on
lockdown for months), and they managed to contain it because they were first
hit and it had not spread far. It has already unfortunately spread widely in
the UK and US.

------
teslaAC
MOST COVID19 CASES ARE ATYPICAL AND NOT REPRESENTED BY ADVERTISED SIDE EFFECTS

ATYPICAL SIDE EFFECTS: Light Fever, Severe Lightheadedness, Long Duration
Headache, Sore Throat, Severe Body Aches, Tight Chest, Very Light Cough No
Phlegm, Sharp Edged Flush on Cheeks with Pale Circle Surrounding Lips, Slight
Runny Nose, Lethargy, Confusion, Hot Flashes, Inconsistant Diarrhoea Without
Discomfort, Trouble Focusing on Conversations, Shakiness, No Issues Breathing
Until Exercise, Flush After Taking Anti-Inflammatories, Very Shakey Legs on
Rising, Swollen Lymph Nodes (under arms), Nervous System Issues: Anxiety,
Change in Perception of Senses, Insomnia These symptoms will cycle and not
present at the same time which is indicative of COVID19

YOU WILL NOT HAVE THE COUGH OR FEVER YOU EXPECT AND MOST PEOPLE BLAME IT ON
STRESS,ALLERGIES,COLD,FLU,ETC.

DO NOT TAKE NAPROXEN, IBUPROFEN OR ANY ANTI-INFLAMMATORIES

Example Symptom Progression From an Interview:

“ I’ve been so tired and so winded and just kind of moody and had a constant
headache for a week and hot flashes mostly at night where it felt like I had a
fever but only at night, random coughing. I figured it was just the weather
and stress. Then last night came to a head—terrible brain fog yesterday could
barely hold a convo, would shake (like when you’re blood sugar crashes) when
I’d try to get up and do something, Had the worst migraine ever last night and
terrible nausea and was throwing up. Then today this is my face with a huge
rash.”

Examples of Corona Rash:

[https://imgur.com/a/dXz52rR](https://imgur.com/a/dXz52rR)

------
013a
During the US coronavirus task force briefing just an hour ago, one of the
heads of the HHS suggested (without outright saying) that one of the reasons
(just one of them) the US is lagging on testing is because they're concerned
about the efficacy of tests other countries are running. High false-positive
and false-negative rates were both mentioned, in "tens of thousands of tests"
distributed to other countries.

There's an underlying truth to this disease that no one has a grasp on right
now, and the only way we get to it is the widespread execution of _accurate_
tests. That doesn't happen quickly. Just think about that the next time you
feel mad about our testing situation; a core doctrine of medicine (at least in
our country) is First, Do No Harm. Telling someone they're infected, when
they're not, is doing harm. Telling someone they're clear, when they're not,
is doing harm. Enacting policy based on numbers derived from a bad test is
doing harm.

And, most importantly, the single thing that represents the entire point of
the doctrine: doing nothing is not doing harm.

~~~
medbrane
>because they're concerned about the efficacy of tests other countries are
running. That's rich. I understand that the US developed test had a lot more
issues that the standard not-invented-here one.

And a lot of countries do the test twice, and only act on double positives or
double negatives.

>doing nothing is not doing harm How can this be OK? People will spread it if
they think they are not sick.

~~~
013a
> And a lot of countries do the test twice, and only act on double positives
> or double negatives.

The false-positivity or false-negativity of a test is not independent across
multiple runs. Its not like each test rolls a dice and decides if it wants to
be accurate or not. Its more accurately based on the human being tested; a
false-positive test for one human would increase the likelihood for a
subsequent false-positive test on that same human. Double-testing helps, but
its not the solution.

> How can this be OK? People will spread it if they think they are not sick.

First, do no harm. This often means the first response for doctors is to do
nothing (and gather information), until they're certain enough that their
actions will not result in harm. Doing nothing is not causing harm; the harm
has already come to their patient. The doctor is not the cause of that harm;
the world caused it. Its a core responsibility of a doctor to not make it
worse accidentally.

Sure, people may spread it if they think they're not sick. But what if a
doctor provides a false-negative result to an asymptomatic patient? Now, that
patient has been told by a doctor "you're fine". They go back to work. Now,
they're spreading it. "My doctor said I'm fine, this little cough is probably
just a cold." Patient doesn't go back to get it checked out again.

What if they provide a false-positive result to an asymptomatic patient? "Wow,
that's crazy. I must have just gotten lucky" the patient says. Two weeks
later, they leave quarantine after getting an accurate negative result. A
month later, they actually contract the disease. "But, that's impossible. I
already had it! My other doctor told me so, he even gave me a Test." Can
coronavirus re-infect patients? Now, we're not so sure. Panic. Research
studies. The truth is obscure.

This is how doctors everywhere operate, and this is true at the FDA/CDC more
than nearly every other country. Our standards for drug development, testing
kit development, etc are among the most stringent in the world. It would take
a disease far, far more deadly than the coronavirus to compromise them.

------
lazyjones
Let's talk about false positives: there seems to be no solid estimate
regarding common Cov-19 tests. I've seen numbers from 40% to 85% in papers
suggesting at least a high number, some of which will probably be sloppily
classified as "asymptomatic" cases.

~~~
robocat
I read that the false positive rate is extremely low (below 1%).

False positives are not a huge problem when you are only testing people with
symptoms. False positives would only become a problem when you are doing a
large number of tests on people who have no symptoms (e.g. 1% of 1 million
people when close to none have the virus).

I think your numbers are the detection rate: false negative rate is high (up
to 40% for early tests).

------
merricksb
Another thread about a Chinese study on this topic:

[https://news.ycombinator.com/item?id=22598803](https://news.ycombinator.com/item?id=22598803)

------
nscalf
I saw a discussion of this on reddit, there was NOT info on if these
individuals eventually developed symptoms, so take this with a grain of salt.

------
MR4D
Why is this post title in English while the actual article linked is in
Italian?

Shouldn’t they have to match?

------
cjohansson
The best way or reducing new positives test-results is by not allowing any new
testing.

------
willart4food
So, how do I know if I am one of those asymptomatic cases?

~~~
timbit42
Assume and act as if you are.

------
GreaterFool
Here’s another question: isolation... and then what?

Sit at home until 2021 when we maybe have a vaccine?

I don’t see how we make this virus disappear so while I can see how people
staying at home can stop the spread, what happens when they leave? Back to
square one?

Maybe UK approach is better.

Maybe we should infect young people deliberately. Here’s Netflix, some books,
some video games, some virus, stay at home for 2 weeks. Build up herd
immunity. Get a paper, move on.

That’s UK approach except they wait for clusters to pop up. Why not make them?
Control the infection rate.

If the chances are everyone gets infected would be better to chose when!

~~~
smichel17
Isolation is too slow the spread. Let the currently sick people get treated,
then let the next wave of people catch the virus, once the hospitals have more
capacity again. The virus is not _that_ dangerous (under 1% fatality) as long
as the healthcare system does not collapse.

------
timwis
Holy cow......I really need to learn Italian

------
hooloovoo_zoo
How reputable is this paper?

~~~
arthens
Very. Repubblica and Corriere are the two main newspapers in Italy, and they
are both quite reliable. Repubblica is left leaning, Corriere is right
leaning.

------
sfj
Googly translation:

[https://translate.googleusercontent.com/translate_c?depth=1&...](https://translate.googleusercontent.com/translate_c?depth=1&nv=1&rurl=translate.google.com&sl=auto&sp=nmt4&tl=en&u=https://www.repubblica.it/salute/medicina-
e-
ricerca/2020/03/16/news/coronavirus_studio_il_50-75_dei_casi_a_vo_sono_asintomatici_e_molto_contagiosi-251474302/%3Fref%3DRHPPTP-
BH-I251454518-C12-P3-S2.4-T1&usg=ALkJrhjf5jbEmuELu9C0C1rvhLi7PpCuHQ)

------
allovernow
Does that mean 25-50% are severe? Is this a bimodal distribution?

~~~
alexanderhorl
Probably not, the other 25-50% get symptoms of which 80% are mild and 20%
severe.

------
olliej
not super surprising - plenty of other diseases are similar.

Even serious things like HIV are contagious for a long time while being
completely asymptomatic.

