See https://www.medrxiv.org/content/10.1101/2020.02.06.20020974v...

> The median incubation period was 3.0 days (range, 0 to 24.0 days)

Edited my post to include that source

Which makes 24 days an extreme outlier

Median and range really says fairly little about the distribution.

Well yes. Yet, since there are so many unknown variables it does not seem incorrect to assume the maximum entropy distribution - Gamma.

It's already an outlier event, it's worth considering the worst cases w.r.t. asking where people have been to determine exposure.

Sure, edited out. Thanks

The most recent study I could find is here:

https://www.medrxiv.org/content/10.1101/2020.02.28.20028068v...

"The mean incubation was 8.42(95% confidence interval [CI], 6.55-10.29) days... COVID-19 course was approximately 2 weeks."

Fairly small sample size of 55 patients, which means the reliability may be debatable, and giving figures to two decimal places is meaningless. (In fact any decimal places are meaningless, unless someone times the exact moment of exposure.)

That aside - it seems very unlikely that 24 day incubations will be common.

Broadly it seems most people who become symptomatic will show symptoms within 10 days and will recover within two weeks after the symptoms appear. A small percentage - mostly older and unwell - will become seriously ill, and an even smaller percentage will die.

Meanwhile the presence of untraceable infections strongly suggests that a significant number of people - possibly a majority - either don't develop symptoms at all, or don't consider them serious enough to require medical attention.

I think there's been news floating around that the virus incubation period could be longer, which is probably where the OP got that number from. See here: https://www.reuters.com/article/us-china-health-incubation/c...

I don't see that supported by the CDC either though

According to this the range is 0-24 days with a median of 3 days. https://www.medrxiv.org/content/10.1101/2020.02.06.20020974v...

Range is between 1-14 days for what percentage? With what level of confidence?

There are several cases where the incubation period has been over 20 days. Maybe 90% of cases incubate for 14 days or less. Maybe 99% for less than 20.

14 days is not some magic limit.

retracted based on feedback

This reply means absolutely nothing, except to drum up alarm.

It's ridiculous nonsense, utterly unsupported by any evidence or mechanism.

> The incubation period is not 25-30 days. The mean incubation period is 5-6 days, range 1-14 days.

There are case reports of it being far longer than 14 days:

https://www.reuters.com/article/us-china-health-incubation/c...

> A 70-year-old man in China’s Hubei Province was infected with coronavirus but did not show symptoms until 27 days later, the local government said on Saturday, meaning the virus’ incubation period could be much longer than the presumed 14 days.

I mean is there a chance they were infected later? E.g. they thought source A caused it but in reality Source B ten days later did?

Maybe, but I just looked the locations in the article, and it looks like his home is in a town in a rural area [1]. Given it's a smaller area, maybe that constrained things enough that they were able to infer that he must have gotten it during his visit to Wuhan. I can imagine several scenarios with an elderly man that might have allowed them to pinpoint his infection to that visit [2]. However, there's just not enough detail in the article to reconstruct how the local Chinese government ruled out everything but his visit as the source of his infection.

[1] Shennongjia, Hubei. Looks like it's a "county" with about 75k people: https://en.wikipedia.org/wiki/Shennongjia

[2] For instance: he visited Wuhan, self-quarantined immediately after returning which limited his contact with others, then 27 days later developed infection. Every contact he did have was tracked and confirmed negative. That's total speculation, though.