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

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

#591
post #470

Earlier quoted context omitted.

It depends. If you're not going to develop symptoms for another 14 days then yeah, you're not infectious. But for a few days before symptom onset you become just as infectious as you will be after symptom onset - which is one of the things that makes this virus hard to stop. A low initial dose doesn't seem to affect the course of the infection much, though. For a sufficiently low dose either none of the viruses find…

I'm very confused by this as I understand that asymptomatic patients are infectious. How does this square with your second sentence?

WHO have maintained for months that asymptomatic patients are not infectious.

Until very recently they still said

"The risk of catching COVID-19 from someone with no symptoms at all is very low."

They now say "Some reports have indicated that people with no symptoms can transmit the virus. It is not yet known how often it happens. WHO is assessing ongoing research on the topic and will continue to share updated findings."

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

#592

Earlier quoted context omitted.

I think it’s the opposite. The initial conditions have a profound effect on the exponential nature of the growth. Half the dose could mean that your immune system can suppress it. There is probably critical rate at which both growth rates match.

I don't think my response is 100% correct. The rate of change (derivative) of an exponetial function is another exponential function. d/dx(2^x) = (2^x)*ln(2). And if the base is e, then d/dx(e^x) = e^x.

Yo people, I don't understand why my statements are correct - please someone with a math background or an epidemiologist comment here, I suck at math and I don't understand how these growth rates compare. My comment is being upvoted but it may not be true.

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

#593
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.

[deleted]

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

#594
post #443

Earlier quoted context omitted.

I don't see them advertising it like that.

The table settings might be nicer, but it's still a chowline of people asses-to-elbows. https://c8.alamy.com/comp/B5D6CE/breakfast-buffet-served-onb...

I guess you guys will have to wait for your first time in jail to spot the differences, if you aren't going to learn from strangers on the Internet

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

#595

Earlier quoted context omitted.

I don't think my response is 100% correct. The rate of change (derivative) of an exponetial function is another exponential function. d/dx(2^x) = (2^x)*ln(2). And if the base is e, then d/dx(e^x) = e^x.

Yo people, I don't understand why my statements are correct - please someone with a math background or an epidemiologist comment here, I suck at math and I don't understand how these growth rates compare. My comment is being upvoted but it may not be true.

Under the exponential growth model, the increased incubation time (before you hit the same total population size) is inversely proportional to the log of the initial dose, so (e.g.) 1/100th of the initial dose gives you only ~7 (log2(100) = 6.64) additional doubling times before arriving at the same population size. While this is not insignificant, it does mean that initial dose is potentially much less important than sources of variability that affect the in-host doubling time.

Edited to add: Here's a preprint that is relevant to the "initial dose vs. immune system response" thought: " rel="nofollow">https://www.medrxiv.org/content/10.1101/2020.03.26.20044487v...

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

#596

One of the more interesting differences between US prison populations and others is that smoking tobacco is way more prevalent: > Estimated smoking prevalence among inmates was approximately 50% in 2003–2004, compared to 21% among noninstitutionalized adults. [0] Which might play a major role in the spread and the actual severity of COVID-19 as French researchers are speculating that nicotine could be responsible for…

On the other hand, in China they saw more susceptibility in men, which many have thought could be related to the cultural norm for men to smoke (and women not to).

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

#597

One of the more interesting differences between US prison populations and others is that smoking tobacco is way more prevalent: > Estimated smoking prevalence among inmates was approximately 50% in 2003–2004, compared to 21% among noninstitutionalized adults. [0] Which might play a major role in the spread and the actual severity of COVID-19 as French researchers are speculating that nicotine could be responsible for…

I could see this making sense for tobacco users that don't smoke (e.g. chewing tobacco) but for people that smoke...I mean this is a respiratory illness. If you have compromised lungs this seems like it would be a nightmare for smokers. Are you concerned at all with the veracity of these claims?

Not at all, I'm merely sharing information that might be interesting to this situation.

Nowhere did I declare anything as fact, I even called something "speculation" by researchers when they don't consider it much one themselves:

> There are however, sufficient scientific data to suggest that smoking protection is likely to be mediated by nicotine. SARS-CoV2 is known to use the angiotensin converting enzyme 2 (ACE2) receptor for cell entry[14-16], and there is evidence that nicotine modulates ACE2 expression[17]which could in turn modulate the nicotinic acetyl choline receptor (manuscript submitted). We hypothesize that SARS-CoV2 might alter the control of the nicotine receptor by acetylcholine. This hypothesis may also explain why previous studies have found an association between smoking and Covid-19 severity[1, 9, 10]. As hospitals generally impose smoking cessation and nicotine withdrawal at the time of hospitalization, tobacco (nicotine) cessation could lead to the release of nicotine receptors, that are increased in smokers, and to a “rebound effect” responsible for the worsening of disease observed in hospitalized smokers.

In that context, it really doesn't matter if this is a "respiratory illness", as nicotine can be applied in a number of ways, like patches.

So even tho it might seem counter-intuitive, this could be part of a plausible explanation why smokers are so underrepresented among COVID-19 patients not just in France, but also in the US and China.

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

#599

Earlier quoted context omitted.

I don't think my response is 100% correct. The rate of change (derivative) of an exponetial function is another exponential function. d/dx(2^x) = (2^x)*ln(2). And if the base is e, then d/dx(e^x) = e^x.

Yo people, I don't understand why my statements are correct - please someone with a math background or an epidemiologist comment here, I suck at math and I don't understand how these growth rates compare. My comment is being upvoted but it may not be true.

The math is a simplification of a biological process that is highly variable and poorly documented. Your original idea is a fine hypothesis, though the suitability of the params behind exponential growth is mostly irrelevant.

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

#600
post #470

Earlier quoted context omitted.

I'm very confused by this as I understand that asymptomatic patients are infectious. How does this square with your second sentence?

WHO have maintained for months that asymptomatic patients are not infectious. Until very recently they still said "The risk of catching COVID-19 from someone with no symptoms at all is very low." They now say "Some reports have indicated that people with no symptoms can transmit the virus. It is not yet known how often it happens. WHO is assessing ongoing research on the topic and will continue to share updated findi…

Yes, the WHO was incorrectly relying upon information provided by China. Since then it has become an accepted fact that asymptomatic transmission of SARS-CoV-2 is not only occurring, but is one of the primary transmission vectors.

https://www.nejm.org/doi/full/10.1056/NEJMoa2008457

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