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Rapid Covid tests miss 90% of asymptomatic cases

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Re: Rapid Covid tests miss 90% of asymptomatic cases

#141

Post by jmull »

mike_hearn wrote: post #105
rlpb wrote: post #42

What I think really matters for most people is not to find out whether they have covid or not, but whether they are infectious or not. I'd really like to see research (any at all!) into how effective different test methods are at predicting infectiousness and am disappointed that this never seems to get addressed. Because who cares if you're asymptomatic but your viral load is low and you're unlikely to infect others…

It was researched and the results were beyond poor, which is why you never heard about them. IIRC ~75% of PCR positive samples couldn't have any virus cultured from them at all. Viral culturing isn't easy, but PCR tests can trigger on destroyed virus, so it's not a surprise that you can't get replicating virus out of many such samples especially at CT>40. But even if you can grow virus, that doesn't mean someone is i…

It's a true tragedy of our time that the CDC, scientific journals, and the media turned to trained epidemiologists for sophisticated pandemic risk assessments rather than random internet guys who find their truth on Twitter. /s

Re: Rapid Covid tests miss 90% of asymptomatic cases

#142

Post by dev_tty01 »

mathgeek wrote: post #71
rlpb wrote: post #42

What I think really matters for most people is not to find out whether they have covid or not, but whether they are infectious or not. I'd really like to see research (any at all!) into how effective different test methods are at predicting infectiousness and am disappointed that this never seems to get addressed. Because who cares if you're asymptomatic but your viral load is low and you're unlikely to infect others…

> What I think really matters for most people is not to find out whether they have covid or not, but whether they are infectious or not. While some folks are certainly still worried about spreading the virus, for most folks it's always been about whether a positive test requires them to restrict their movement or activities (e.g. whether or not one could fly on a plane in 2020-2022).

That may be true for most, but there are many of us who interact with at-risk people (elderly parents, an immune suppressed family member, etc.) and the daily concern is whether or not I might be infectious and potentially bring harm to someone else. I don't care if I have Covid if I can't spread it to someone else.

Public service request: There are millions of Americans with compromised immune systems who are finding the current environment treacherous since most people have completely moved on. If we have an interaction with someone who is masked, it would be great if we could just mask up at least during that interaction as a courtesy. That person could be at significant risk and it does no harm to us to mask up for a few minutes to help reduce their risk even if we aren't concerned for ourselves.

Re: Rapid Covid tests miss 90% of asymptomatic cases

#143

Post by 111111IIIIIII »

maxbond wrote: post #108
harha wrote: post #85

Earlier quoted context omitted.

I can figure out for myself if I have symptoms or not

Sometimes in society, we adopt laws that are about keeping other people safe more than they are about keeping yourself comfortable. You might feel inconvenienced. Ultimately, you're the beneficiary of this too. Your life is going to be a lot longer, because the people around you are occasionally inconvenienced for your benefit. If this isn't acceptable to you, I'm sorry about that, that's tough.

[flagged]

Re: Rapid Covid tests miss 90% of asymptomatic cases

#144

Post by taeric »

amelius wrote: post #6

Is that really a problem if asymptomatic cases are less infectious and do not cause much issues to the carrier? (This is a question, not a statement)

I think the big problem is that a large number of "asymptomatic" cases can also be seen as "presymptomatic?" And it is not fully clear on when you would flip to being a carrier/spreader.

Re: Rapid Covid tests miss 90% of asymptomatic cases

#145

Post by maxbond »

spamizbad wrote: post #119
harha wrote: post #85

Earlier quoted context omitted.

I can figure out for myself if I have symptoms or not

How? I wouldn't know the difference between a seasonal cold (or flu) or COVID, mostly because I've never had COVID.

Every time I've gotten together with my family for Christmas the past few years, a very virulent infection has ripped though the household, getting everyone sick within a week, and taking me out of commission for a large part of the trip.

Every time I think to myself, "this is it, we all got COVID. I can tick off the symptoms."

None of those times were COVID (as confirmed by PCR tests).

More recently I was getting ready to go meet a newborn family member. I felt a little off so I took a Rapid Test. Guess what? I had COVID.

That Rapid Test stopped me from introducing COVID into a household with a newborn baby and parents trying to stay healthy to take care of their newborn baby.

Re: Rapid Covid tests miss 90% of asymptomatic cases

#146

Post by blagie »

worldsavior wrote: post #59
blagie wrote: post #37

Earlier quoted context omitted.

I actually think it's the opposite. There is a hyper-polite culture in the west where people tone down statements: - It's [X] - Have you considered it might be [X]? - Is it possible it might be [X]? - ... The goal is to not appear overly assertive / confident / arrogant. Once that happens, people start to read subtexts into questions, and all of a sudden, you need disclaimers. I like direct communications, so I find…

What you're mentioning is good and reasonable criticism. This is not what I'm talking about. You don't have to mention anything and be afraid of what people might say because you don't want toxic behavior towards you. People need to stop. Read, understand, conclude and write. This is basic communication.

This is basic communication within a traditional setting. There are at least two issues:

1) In a multicultural setting, words written and words read may carry different meaning. Words carry subtly different meanings, and tones and subtexts need to be translated.

2) Unless one takes 2 hours to draft each email, people will misspeak.

Miscommunications are part of life. Any process needs to account for that.

Re: Rapid Covid tests miss 90% of asymptomatic cases

#147

Post by Timon3 »

willcipriano wrote: post #49
oldandboring wrote: post #36

Earlier quoted context omitted.

Wouldn't it also stand to reason that these people are asymptomatic because they have low viral load, and low viral load means less virus in the air they expel, reducing spread?

Not more so than if they stayed home.

But that "staying home" only holds once you feel symptoms, and only until you don't stay anymore. During that specific time they might infect fewer people. Before and after it would be the other way around.

Re: Rapid Covid tests miss 90% of asymptomatic cases

#148

Post by blagie »

pc86 wrote: post #116
blagie wrote: post #38

Earlier quoted context omitted.

unlikely ≠ won't Defense-in-depth gives a broad range of tactics, and the goal is to combine enough of them to limit risks.

"won't" isn't a reasonable standard. People get sick. You get other people sick. Other people will get you sick. It happens, and completely eliminating every occurrence is not a valid or reasonable goal.

Going from 50% to 75% to 88% to 94% to 97% to 99% to 99.5% reduction in risk carries an exponential increase in cost. Bringing risk to zero isn't a reasonable -- or possible -- goal, but how much this should decrease depends on individual and cultural profiles.

If you think one risk profile is reasonable, and you're interacting with someone who has a much more conservative profile and putting them at risks they consider unreasonable, you're probably being a dick (and vice-versa). That's not just diseases -- it's everything from gun safety to outdoors safety to sparring.

If you've been exposed to covid, and are asymptomatic, you should take reasonable precautions. For introverts, that might be staying at home. For others, it might be testing. For others, it might be using a high-filtration mask. It sort of depends on your preferences. Asymptomatic spread is pretty common, and it's not unreasonable to try to prevent it.

If you've been exposed to covid and are symptomatic, you should take stronger precautions.

Re: Rapid Covid tests miss 90% of asymptomatic cases

#150

Post by mike_hearn »

gcanyon wrote: post #120
mike_hearn wrote: post #105

Earlier quoted context omitted.

It was researched and the results were beyond poor, which is why you never heard about them. IIRC ~75% of PCR positive samples couldn't have any virus cultured from them at all. Viral culturing isn't easy, but PCR tests can trigger on destroyed virus, so it's not a surprise that you can't get replicating virus out of many such samples especially at CT>40. But even if you can grow virus, that doesn't mean someone is i…

I've read several of your responses here, and thanks for the info, but I have to say, your tone comes off as "I know better and would have been more sensible if I were in charge." When you're in the heart of an epidemic that's going to kill millions, you err on the side of caution. Quarantining you at home, for example, makes sense when you're dealing with a deadly disease and you don't know enough to know you're not…

> Quarantining you at home, for example, makes sense when you're dealing with a deadly disease

Intuitively yes, in reality no. It was known by March 2020 that quarantines had no effect because of the outcome of trying it on the Diamond Princess, a sealed environment where quarantine could be perfectly enforced. That didn't stop SARS-CoV-2 spreading between cabins and causing COVID apparently at random, i.e. it'd propagated everywhere but not everyone was susceptible. This knowledge was never incorporated into health policy. The same thing had been found during the SARS-1 outbreak in Hong Kong, where it was able to move between apartment blocks separated by a garden on air currents. The quarantine within the origin apartment block didn't work due to airborne transmission, something the WHO denied was possible.

It was even known before 2020. Public health planning before this time said clearly not to use mass testing and mass quarantines because they don't work. This was torn up once COVID started.

> your tone comes off as "I know better and would have been more sensible if I were in charge."

Frustrated, yes, I know how it sounds.

The COVID response was deeply flawed from the start, and in ways that were obvious even to outsiders. I was writing about the impossible claims being made for PCR tests and the history of failed epidemic models in Spring 2020, but I don't think I'd have done better if I ran the WHO. That's because the incentives and structures such people operate under are terrible, and apparently overwhelmingly strong.

Consider this article from 2010 [1]. Der Spiegel investigated the Swine Flu "mass hysteria" and stated that the world clearly overreacted. Reporting on the WHO, "At any rate, efforts to downplay the risks were unwelcome, and the WHO made it clear that it preferred to base its decisions on a worst-case scenario. "We wanted to overestimate rather than underestimate the situation," says Fukuda."

Given everything that happened since I'm really convinced that the right way to handle a pandemic is just to let individuals and their doctors get on with it. Academics and NGOs can make recommendations if they want, but giving these people power is a bad idea. Central health planners are incentivized to maximally over-react, every single time. No lessons are ever learned, and why would any be? They have absolute immunity from accountability and consider interventions to be cost free. That is corrupting. What happened with COVID will happen again.

[1] https://www.spiegel.de/international/world/reconstruction-of...

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