CDC: As many as 25 percent of people infected with the coronavirus do not develop symptoms.

[denem]

Infected but Feeling Fine: The Unwitting Coronavirus Spreaders

The C.D.C. director says new data about people who are infected but symptom-free could lead the agency to recommend broadened use of masks.

As many as 25 percent of people infected with the new coronavirus may not show symptoms, the director of the Centers for Disease Control and Prevention warns — a startlingly high number that complicates efforts to predict the pandemic’s course and strategies to mitigate its spread.

... “This helps explain how rapidly this virus continues to spread across the country,” the director, Dr. Robert Redfield, told National Public Radio in an interview broadcast on Tuesday.

... (An) analysis of the hundreds of people cloistered aboard the Diamond Princess cruise ship bears out this scale. Once the ship docked in Japan on Feb. 5, researchers tested all of the passengers and reviewed those who tested positive for the virus on multiple occasions over a two-week period. They found that 18 percent of the infected passengers remained symptom-free throughout.

“The substantial asymptomatic proportion for Covid-19 is quite alarming,” said Dr. Gerardo Chowell, an epidemiologist at Georgia State University who worked on the analysis.

Dr. Chowell noted that the passengers on the ship tended to be older and therefore more likely to develop symptoms. He estimated that about 40 percent in the general population might be able to be infected without showing signs of it.

https://www.nytimes.com/2020/03/31/health/coronavirus-asymptomatic-transmission.html

20% of people with seasonal influenza do not develop symptoms.

[woodsprite]

1. Which means that we SHOULD be wearing masks of somekind when we go out. nt

[In_The_Wind]

2. imho: yes

[denem]

3. They were lying to us.

There is a reason that masks are compulsory in most of Asia.

[we can do it]

4. Medical staff have no equipment. We can use bandanas.

[denem]

5. A lie is still a lie.

Yes medical professionals must take complete precedence over the general population, but and behold, the CDC is changing its advice, with 'new data' that was available in China and Japan two months ago.

[JudyM]

11. Exactly! Same for the long-delayed acknowledgement that it's airborne, and more recently,

that a nasal swab is often false negative, because it’s still live in fecal swabs. Taking someone’s temperature before allowing him/her into a senior residential community is only going to catch some of folks with the virus.

[Sunsky]

7. How effective are bandanas?

I hear people sanctioning this but what's the evidence on it's efficiency? The CDC recommended homemade mask as a last resort and said it should be used with other protective gear such as a face shield.
I'm a healthcare worker and yes we do need supplies but I am also fearful that people will be lured into a false sense of protection with these simple cloth covering that offer very minimal to no protection.

[JudyM]

12. Depends on the fabric, the number of layers and how closely it conforms to your face.

Even a bandana is better than nothing, though. There are some studies of this online you can find, using different kinds of masks, as well... interestingly, surgical masks aren’t that much less effective than the n95s.

Oh and BTW, 160 degrees and also just UV light (including sunshine) will kill virus on masks, etc. based on what I’ve read.

[woodsprite]

8. I admit it shamefully. I'm a craft hoarder.....

BUT that means that we have some squirreled away fat quarters that are 100% cotton, some bias tape, and are making double layered masks w/ pockets for family and donations. The pocket means they can add another type of filter if they have it. We also are making the 2 sides different colors so someone can tell what is the outside and what is the inside.

I figured any mask is better than no mask at all. Even if it's to keep us from *giving* it to someone if we're one of the asymptomatic 20-40%.

The hospital said that they will turn to the homemade items when they run out of their normal masks to give patients that are being treated. Our local fire department said the same thing - especially since numbers are on the rise here of infections in health care workers.

[captain queeg]

6. This shows the need for widespread testing

And determine who has had it and is now immune.

[DeminPennswoods]

9. The question is what makes these "infected" people

not get sick. I'd want a blood sample from them to see if they have more or different antibodies than those who do get symptoms.

Here is an interesting article from the New Yorker about similar "seed or soil" questions with cancer: https://www.newyorker.com/magazine/2017/09/11/cancers-invasion-equation

[denem]

10. A working hypothesis is exposure to 229E and/or OC43

coronaviruses that cause the common cold.

[Quixote1818]

15. Interesting but what about all the asymptomatic children?

They certainly haven't been exposed to very many colds yet.

[DeminPennswoods]

17. Wouldn't they have gotten some immunity from their

mother's blood via the umbilical cord?

[denem]

18. The ACE-2 receptors that SARS-CoV-2 attaches to

increase with age. Children have relatively few, so that they are generally receiving low doses of the virus. For the same reason, medical professionals can be subject to high doses of the virus, and the resultant COVID-19 is serious.

[DeminPennswoods]

16. Interesting

that would support the emerging theory that older adults are actually less susceptible because they've been exposed to more virus/bacteria over their lifetimes than younger people.

[Quixote1818]

13. In Iceland and on the Diamond Princess it is closer to 50%

Iceland’s testing suggests 50% of COVID-19 cases are asymptomatic

https://www.zmescience.com/medicine/iceland-testing-covid-19-0523/?fbclid=IwAR3SLRNNdMh1QcNtOJ7BkoM_dJ2jaQ7uulyCmCFlv-p2jJsQJo5XNPledpI

Nearly half of Diamond Princess cruise ship passengers, crew who had coronavirus were asymptomatic when tested, CDC report says

https://whdh.com/news/nearly-half-of-diamond-princess-cruise-ship-passengers-crew-who-had-coronavirus-were-asymptomatic-when-tested-cdc-report-says/?fbclid=IwAR1gpps5xBWdln0BG-dWngDoCK74QwmNiAaRV6XFosQU6LBEo3F3glgjODA

[Quixote1818]

14. That is a crap load of Typhoid Mary's out there. nt

[mathematic]

19. The higher this number, the better

Fewer people to get sick in the future.