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Coronavirus clue? Most cases aboard U.S. aircraft carrier are symptom-free

reuters.com

461–470 of 544 posts

Re: Coronavirus clue? Most cases aboard U.S. aircraft carrier are symptom-free

#461
post #239

Earlier quoted context omitted.

That would be a very obvious thing to detect (and we have not seen evidence of that).

evidence of what? two separate strains? this paper mentions two strains[0], 'L' and 'S' type, was it refuted? [0]: https://academic.oup.com/nsr/article/doi/10.1093/nsr/nwaa036...

Evidence of one, less dangerous, strain, followed by a more dangerous strain that arrived months later. No such evidence exists.

Re: Coronavirus clue? Most cases aboard U.S. aircraft carrier are symptom-free

#462
post #409

Earlier quoted context omitted.

> The 2% number is 2% of people who have bad symptoms die. I don't believe that's true. In countries such as Spain, right now there are about 80k confirmed recoveries and 19k deaths among a universe of 182k confirmed cases.

We don't know. There are probably a lot of cases in Spain that are flying under the radar because people without symptoms don't get tested often.

OP's claim was that "2% of people who have bad symptoms die."

From Spain's numbers, around 10% of those experiencing symptoms that lead them to get tested by Spain's health service, which due to scarcity is reserved for serious cases and people on the front lines, have died since the onset of the epidemic.

Re: Coronavirus clue? Most cases aboard U.S. aircraft carrier are symptom-free

#463
post #49
post #15

Earlier quoted context omitted.

Agree, though still a long way from herd immunity, which I understand starts at 50%-ish.

Herd immunity varies by disease. A lot. For each disease we estimate a number called R0, which is how many people the average person will transmit it to if no precautions are taken. Herd immunity sets in when only 1/R0 people have not managed to get it. With the flu, R0 is about 1.3. Meaning that herd immunity to a particular strain starts slowing the spread after about 1/4 of us are immune. (It can continue spreadin…

Could you post a working version of that link? Most R0 estimates I have seen are between 2.5 and 3.5. 5.6 seems really high to me.

It is worth considering that even if the % immune is lower than the herd immunity level, it still slows the outbreak and reduces Re. That gives us a much slower ramp up and gives other measures like less restrictive social distancing, contact tracing, etc. a chance to work. Even if all those together only get Re down to between 1 and 2, we still benefit since it means we might only need another 1 or 2 lockdown periods before we get an effective vaccine.

Re: Coronavirus clue? Most cases aboard U.S. aircraft carrier are symptom-free

#464
post #49

Earlier quoted context omitted.

Herd immunity varies by disease. A lot. For each disease we estimate a number called R0, which is how many people the average person will transmit it to if no precautions are taken. Herd immunity sets in when only 1/R0 people have not managed to get it. With the flu, R0 is about 1.3. Meaning that herd immunity to a particular strain starts slowing the spread after about 1/4 of us are immune. (It can continue spreadin…

Could you post a working version of that link? Most R0 estimates I have seen are between 2.5 and 3.5. 5.6 seems really high to me. It is worth considering that even if the % immune is lower than the herd immunity level, it still slows the outbreak and reduces Re. That gives us a much slower ramp up and gives other measures like less restrictive social distancing, contact tracing, etc. a chance to work. Even if all th…

I think it's this link: https://www.medrxiv.org/content/10.1101/2020.02.07.20021154v...

Re: Coronavirus clue? Most cases aboard U.S. aircraft carrier are symptom-free

#465
post #351

IMHO, this article is intentionally misleading. The incubation period is currently estimated to be 2-14 days (mean is 5.6 days per CDC, similar per WHO). The article doesn’t mention any dates or time frames, but does mention: ”Roughly 60 percent of the over 600 sailors who tested positive so far have not shown symptoms of COVID-19” — note how “so far” is ambiguous in that sentence. It also states, “The Navy’s testing…

They really needa handle this

Re: Coronavirus clue? Most cases aboard U.S. aircraft carrier are symptom-free

#466
post #439
post #412

Earlier quoted context omitted.

It's just splendid how a lot of people will criticize an estimate of deaths assuming no mitigating measures, and then say "see? no problem!" when the outcome is much better after stopping most economic activity for a month. War-time level mitigating measures.

Yeah - actually worse than wartime level, for a lot of wars. If you look at economic indictors for ww2 for the UK or USA they are actually less bad, less sudden, than this lockdown. Also if you think about the restrictions placed and the number of people affected.

When you look at countries where front was, it looks different. It is quite cherry picking to pick the best off countties. One of then had no war on its soil (and earned finacially overall).

Re: Coronavirus clue? Most cases aboard U.S. aircraft carrier are symptom-free

#467
post #446

Earlier quoted context omitted.

Not when the amount of people is limited. Exponential spread in isolated group of 3000 people necessary becomes non exponential at some point.

> becomes non exponential at some point From some simple calculus, becomes the (a) logistic curve.

Regardless of calculus, it becomes constant at one point. Latest when everyone is infected.

Re: Coronavirus clue? Most cases aboard U.S. aircraft carrier are symptom-free

#468
post #446

Earlier quoted context omitted.

If the virus spreads exponentially, you would expect most cases to be presymptomatic at any given time.

Not when the amount of people is limited. Exponential spread in isolated group of 3000 people necessary becomes non exponential at some point.

Eh, so far only 600 of the 4800 member crew has tested positive. That should still be comfortably in the "mostly exponential" territory.

Re: Coronavirus clue? Most cases aboard U.S. aircraft carrier are symptom-free

#469
post #442

Earlier quoted context omitted.

If 0.37% is true, why are the hospitals in this shape?

.0037 * 83,700,000 = 309,690 additional people

It's still going to be a giant number, but I recommend including the fraction estimated to catch the disease, in this case 0.7 because diseases with an R0 of 2-2.5 typically infect 70% of the population.

Re: Coronavirus clue? Most cases aboard U.S. aircraft carrier are symptom-free

#470
post #333

Earlier quoted context omitted.

I thought there had been cases of people getting reinfected, and that how long the immunity lasts seemed to correlate to how sick you'd been. So the immunity of asymptomatic people wouldn't last very long. Maybe it'll last long enough to make a dent in the infection rate?

> I thought there had been cases of people getting reinfected, and that how long the immunity lasts seemed to correlate to how sick you'd been. What they found so far is that some people had lower levels of antibodies than others, but that it did not correlate to how sick they were. It's also not clear at this point that anyone's been re-infected (although it is possible) because it's much more likely they hadn't rec…

And if some people can be reinfected after one exposure, it's not necessarily a death knell for a potential vaccine -- you get multiple boosters for some viruses for a reason, and the vaccine just has to take in a large enough fraction of the population to protect everyone.
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