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In 4 US state prisons, 3,300 inmates test positive, 96% without symptoms

reuters.com

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Re: In 4 US state prisons, 3,300 inmates test positive, 96% without symptoms

#511

Post by tim333 »

djsumdog wrote: post #461
icegreentea2 wrote: post #384

Earlier quoted context omitted.

The sensitivity of PCR tests to SAR-COV-2 varies over time from time to infection. I think the the OP is overestimating how narrow this window is though. It's not like you need to test within a few days or a week to be positive - it's just that viral load is maximum for only a few days (roughly the +/-3 days around onset of symptoms). Even after the viral load in the upper respiratory tract drops off, there's still l…

Is this test sensitive to just SARS-CoV-2? What is the possibility that other corona viruses (like the ones that cause many of our colds) could create a false positive? I haven't heard anything from a reliable source on that.

PCR is pretty selective for SARS-CoV-2

Re: In 4 US state prisons, 3,300 inmates test positive, 96% without symptoms

#512

Post by godelski »

lyjackal wrote: post #410
danieltillett wrote: post #361

Earlier quoted context omitted.

A prison is very much like a cruise ship from a viral perspective. We know from the cruise ship data like the Diamond Princess that most people had no symptoms initially, but overtime most people became symptomatic [1]. Of course if we are really lucky and the prison was infected with a naturally attenuated strain we should make use of it [2]. 1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7078829/ 2. https://www.ti…

Prison demographics are very different than cruise ships, so might be interesting if different

To give evidence to this comment, the gp's source notes that ~75% of those that tested positive for covid were >60 years old. Whereas the BOP [0] reports a distinctly different age demographic. We know that covid dramatically affects people differently based on age, so I wouldn't suspect IFR to be similar to that of a cruise ship (where it is typical for the demographic to be older and retired)

[0] https://www.bop.gov/about/statistics/statistics_inmate_age.j...

Re: In 4 US state prisons, 3,300 inmates test positive, 96% without symptoms

#513

Post by tim333 »

reddothomme wrote: post #462
finolex1 wrote: post #331

To add another data point, Singapore has been testing foreign workers living in dormitories extensively, uncovering about 10,000 cases (about 80% of the country's total cases). These are relatively fit individuals between the ages of 20 and 40. However, the number of people in the ICU has remained remarkably consistent at about ~20 people in the past 10 days (Fingers crossed it remains that way). https://www.moh.gov.…

Many migrant workers in Singapore are the only breadwinners for their families back home in Bangladesh/India/Myanmar. One of the reasons the Singapore government has done extensive testing way beyond global standards is that many of these foreign workers are financially disincentivized to seek medical help the moment the first symptoms appear. The fact that Singapore's leader has publicly promised stable incomes for…

Thailand just yesterday reported some.

Re: In 4 US state prisons, 3,300 inmates test positive, 96% without symptoms

#514

Post by RangerScience »

bumby wrote: post #271
vinceguidry wrote: post #266

Earlier quoted context omitted.

That doesn't rule out a high false positive rate. The false positive rate can be even higher than the false negative rate.

Totally agree. The difference being a high false negative rate may be more dangerous because it may mean asymptomatic false negative carriers are still spreading the virus. The downside of a false positive is that people are self quarantining needlessly. For a patient, a high false negative rate is usually worse. For an insurer, a high false positive rate is usually worse. The perspective matters.

What appears to be the potential danger of a high false positive is the narrative that it's safe to end stay-at-home because everyone already has/had it. Which seems to be the story being pushed with any talk of a lot of positives.

Re: In 4 US state prisons, 3,300 inmates test positive, 96% without symptoms

#515

Post by suzzer99 »

Gibbon1 wrote: post #349
jwlake wrote: post #137

One of the super-interesting things here, is that apparently everyone was in the specific window where they test positive for the virus. This implies the population was recently infected, had not been previously infected, and it spread almost completely within a tight window. This implies a shocking high R(effective) for that population. In 2 weeks we'll have super interesting data one way of the other on the CFR.

I repeatedly point this out. There was the church choir practice where 45 out of 60 people were infected within what two hours? There is also a Korean call center where about 2/3 of the people in an open office were infected. I've repeatedly linked to CDC study that estimates r0 in Wuhan before lockdown at between 3.8 and 8.7. Median 5.8. Take away: Completely avoid being indoors with large groups of people.

Especially if they're singing or talking non-stop.

Re: In 4 US state prisons, 3,300 inmates test positive, 96% without symptoms

#516

Post by jfnixon »

greedo wrote: post #473
rubber_duck wrote: post #444

Earlier quoted context omitted.

You can self isolate without quarantine measures in effect so your point isn't that strong to me and you are ignoring that one of the biggest destabilising forces in history is economic downturn. US-China relations have been bad for a while now and both sides are throwing blame at each other as a populist policy (China has a US origin story allegedly). If this pushes the economy in to a global depression who knows wh…

Self-isolating vulnerable populations is almost impossible. You're talking over 100M in the US. And not doing anything (pretend it's just the flu) will result in 50M dead world wide. Everyone worried about a new depression should realize one is going to happen no matter what we do now. The only thing we can do is act in a humane fashion.

Your number is highly suspect. About 16% of the US is 65+, or roughly 50M.

Where do you get your 50M worldwide figure? When a new flu appears, Neil Ferguson claims his 3K lies of undocumented C code forecast 200M will die. These numbers are all speculation and worse predictors than throwing darts at a board behind your back.

Re: In 4 US state prisons, 3,300 inmates test positive, 96% without symptoms

#518

Post by suzzer99 »

raverbashing wrote: post #140
ptrincr wrote: post #58

Earlier quoted context omitted.

Not sure why you are being downvoted: https://www.oxfordbiosystems.com/COVID-19-Rapid-test "In order to test the detection sensitivity and specificity of the COVID-19 IgG-IgM combined antibody test, blood samples were collected from COVID-19 patients from multiple hospitals and Chinese CDC laboratories. The tests were done separately at each site. A total of 525 cases were tested: 397 (positive) clinically confirmed…

I wonder what's the process through which false positives happen in this case. Previous infection by milder Coronaviruses? Edit: I'm looking at the reddit post but I have a lot of reservations with the "prevalence 0.06", unless we'll use the test to test absolutely everybody and not only people who are suspect. Has that calculator been validated as well? If the test was 12 false positives in 128 negatives, how come t…

This is from ARCPoint Labs, where I took my antibody test:

The Antibody test is a serology test which measures the amount of antibodies or proteins present in the blood when the body is responding to a specific infection. This test hasn’t been reviewed by the FDA. Negative results don’t rule out SARS-CoV-2 infection, particularly in those who have been in contact with the virus. Follow-up testing with a molecular diagnostic lab should be considered to rule out infection in these individuals. Results from antibody testing shouldn’t be used as the sole basis to diagnose or exclude SARS-CoV-2 infection. Positive results may be due to past or present infection with non-SARS-CoV-2 coronavirus strains, such as coronavirus HKU1, NL63, OC43, or 229E.

Re: In 4 US state prisons, 3,300 inmates test positive, 96% without symptoms

#519

Post by _-___________-_ »

cameldrv wrote: post #378
danieltillett wrote: post #361

Earlier quoted context omitted.

A prison is very much like a cruise ship from a viral perspective. We know from the cruise ship data like the Diamond Princess that most people had no symptoms initially, but overtime most people became symptomatic [1]. Of course if we are really lucky and the prison was infected with a naturally attenuated strain we should make use of it [2]. 1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7078829/ 2. https://www.ti…

I think that. depending on the air conditioning system, it might be quite a bit worse. The density of people is huge, air flows freely between cells, prisoners eat packed together at communal tables. I bet R is like 10-20.

I'd have thought that more airflow would help to reduce transmission, given that like other coronaviruses it's transmitted by droplets and not aerosol. Droplets would have trouble staying suspended with more air movement, and would be unlikely to make it through centralised air conditioning systems without becoming deposited on some surface within them.

The eating together at communal tables, and any other close-quarters communal activities, seem far more relevant to increased R than the air conditioning system and the free airflow.

Re: In 4 US state prisons, 3,300 inmates test positive, 96% without symptoms

#520

Post by qznc »

jwlake wrote: post #137

One of the super-interesting things here, is that apparently everyone was in the specific window where they test positive for the virus. This implies the population was recently infected, had not been previously infected, and it spread almost completely within a tight window. This implies a shocking high R(effective) for that population. In 2 weeks we'll have super interesting data one way of the other on the CFR.

We will also see if they are asymptomatic or presymptomatic.
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