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Coronavirus

Started by bacardiandlime, January 30, 2020, 03:20:28 PM

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sprout

Quote from: Anselm on June 13, 2020, 06:08:53 PM
I just had 2 Covid-19 tests this past week, one before entering the hospital and then another before having a procedure done.  The tests are not fun.

Agreed.  When I had one a couple months ago, I was told 'if your eye doesn't water, I'm not in the right spot!'  I think he was mostly not joking.

Wahoo Redux

Hey biologists and zoologists, I think Fauci said that corona viruses tend not (or are less likely) to mutate.  Am I understanding that correctly? 

Is the virus we see now the virus we are going to have to deal with from now on?
Come, fill the Cup, and in the fire of Spring
Your Winter-garment of Repentance fling:
The Bird of Time has but a little way
To flutter--and the Bird is on the Wing.

mamselle

Umm....hmmmm....I thought I read the opposite, that they had mutated several times and that was part of the reason they became so peripatetic: they could hitch-hike on different species because of sequence changes.

Being recombinant, I think that makes them more agile in that regard, but I've only worked for biochemists, I not are one.

This is one of the articles that made me think that.

   https://www.healthline.com/health-news/what-to-know-about-mutation-and-covid-19#Just-how-long-will-immunity-last?

As the title suggests, it may be harder to build an efficacious vaccine against mutation-prone viruses.

M.
Forsake the foolish, and live; and go in the way of understanding.

Reprove not a scorner, lest they hate thee: rebuke the wise, and they will love thee.

Give instruction to the wise, and they will be yet wiser: teach the just, and they will increase in learning.

namazu

#618
Quote from: Wahoo Redux on June 16, 2020, 12:11:30 PM
Hey biologists and zoologists, I think Fauci said that corona viruses tend not (or are less likely) to mutate.  Am I understanding that correctly? 
Is the virus we see now the virus we are going to have to deal with from now on?
Coronaviruses tend to be more stable than, say, flu viruses, but they are not static, and they are subject to selective pressures.

There have been some mutations identified to date, some of which seem to have no/limited functional effect, and some of which may have resulted in changes in transmissibility (e.g. of the European strains that came to dominate in much of the U.S., vs. the earlier strains circulating in China).

The larger the number of infections, the larger the number of times the virus replicates, and the more opportunities there are for the virus to mutate. 

It's not clear at this point whether/to what extent these mutations may affect the efficacy of potential vaccines or their utility over longer periods of time. 

Most vaccines under development are targeting the spike protein on the surface of the virus shell. You can think of the spike protein as a kind of flag that the immune system can recognize and target.  If mutations make this flag a different shape or color or size, then it may be more difficult for an immune system trained to recognize the original version of the flag to recognize the new/mutated version and mount an effective immune response.  So the implications of mutations for vaccines depend on just how any given mutation changes the relevant immune system targets.  They may be deal-breakers, or they may not be.

the_geneticist

Quote from: Wahoo Redux on June 16, 2020, 12:11:30 PM
Hey biologists and zoologists, I think Fauci said that corona viruses tend not (or are less likely) to mutate.  Am I understanding that correctly? 

Is the virus we see now the virus we are going to have to deal with from now on?

Well, that is the $10 billion question.
All viruses mutate.  The SARS-CoV-2 virus has the ability to "proofread" and correct mistakes made while copying it's genome so it is less prone to mutation that other RNA viruses.
Whether or not the mutations will alter the virus' ability to infect human cells or replicate is what we'll have to wait and find out.
Or whether it's possible for the virus to mutate in a way that would make a particular vaccine less effective.  That's why most of the vaccines being developed are designed against what we think are the most-conserved & important (i.e. least likely to be changed) parts of the virus.

clean

I recently added access to netflix. There is a documentary series called Pandemic. I have only seen the first 4 episodes, so I dont know what the conclusions are, but one of the early subjects of the series is a company that is fighting the flu by attempting to find something that is unchanging in the virus.  So far (as I ve watched) they can find immunity to most flue strains, but it requires that one takes a series of Seven! Shots! 

Personally, i would be glad to take seven shots to have nearly full immunity to the flu, but I guess that I may not be typical, or that the cost of 7 different shots would be uneconomical.

Perhaps there is something in CV19  or with its cousins that is common that could be found that would work for most of the possible mutations!
Of course IF/when that 'one factor' DID change, the usefulness of the shot would be lost or at least greatly reduced.
"The Emperor is not as forgiving as I am"  Darth Vader

Caracal

Just an update from a discussion long, long ago...

https://www.nature.com/articles/s41591-020-0962-9

Seems like pretty strong evidence that kids actually do get infected at much lower rates.

Caracal

Quote from: clean on June 16, 2020, 02:42:21 PM

Perhaps there is something in CV19  or with its cousins that is common that could be found that would work for most of the possible mutations!
Of course IF/when that 'one factor' DID change, the usefulness of the shot would be lost or at least greatly reduced.

Not a scientist, but the people who work on this have argued that COVID mutations aren't significant at this point and probably don't change the behavior of the virus. This is a good laypersons summary. https://www.businessinsider.com/coronavirus-mutations-strains-scientists-track-genetics-2020-4

science.expat

Quote from: sprout on June 16, 2020, 08:37:44 AM
Quote from: Anselm on June 13, 2020, 06:08:53 PM
I just had 2 Covid-19 tests this past week, one before entering the hospital and then another before having a procedure done.  The tests are not fun.

Agreed.  When I had one a couple months ago, I was told 'if your eye doesn't water, I'm not in the right spot!'  I think he was mostly not joking.

I had a test yesterday and it was fine. Uncomfortable but not painful. And I received the negative result by SMS about 15 hours later. ☺️

Treehugger

Has anyone here wondered about the safety of drive-by testing? I am not sick and have no reason to go get myself tested, but if I were feeling sick, I know I would be hesitant. It just seems like the perfect way to pick up Covid if you don't already have it. I know they take precautions, but they don't change their protective gear after after single person, so it stands to reason that if they did encounter someone with Covid, the exterior of their PPE could be shedding the virus. And, of course, even if you are in your car, they still need access to your face.

Caracal

Quote from: Treehugger on June 17, 2020, 04:06:21 AM
Has anyone here wondered about the safety of drive-by testing? I am not sick and have no reason to go get myself tested, but if I were feeling sick, I know I would be hesitant. It just seems like the perfect way to pick up Covid if you don't already have it. I know they take precautions, but they don't change their protective gear after after single person, so it stands to reason that if they did encounter someone with Covid, the exterior of their PPE could be shedding the virus. And, of course, even if you are in your car, they still need access to your face.

Again, not at all an expert, but objects don't "shed" virus. It doesn't alight on something and then go airborne again. The other thing is that the dose matters. If you're imagining some scenario where a tester gets virus particles on their mask and then the wind blows or whatever, by the time all that happened you would be talking about amounts way too small to make you sick.

Bonnie

Quote from: Treehugger on June 17, 2020, 04:06:21 AM
Has anyone here wondered about the safety of drive-by testing? I am not sick and have no reason to go get myself tested, but if I were feeling sick, I know I would be hesitant. It just seems like the perfect way to pick up Covid if you don't already have it. I know they take precautions, but they don't change their protective gear after after single person, so it stands to reason that if they did encounter someone with Covid, the exterior of their PPE could be shedding the virus. And, of course, even if you are in your car, they still need access to your face.

I think it is a very, very low risk situation. I don't think there is evidence that the PPE (or other objects) sheds the virus. And even if the person in the car in front of you shed a bit of virus in the air as they tested, it's not going to be enough to get you sick when you pull up in the space. The amount of time you are there is not significant. (Risk is about viral load in the air plus distance plus TIME). And at least here, they don't need access to your face. They hand you the swab (with their gloved hands, gloves that are changed after each test), you hand it back.

pigou

Quote from: Bonnie on June 17, 2020, 05:09:13 AM
They hand you the swab (with their gloved hands, gloves that are changed after each test), you hand it back.
That seems like an awful way to do it. A proper sample requires you to stick that swab WAY up your nose and I can't imagine doing that to myself. If this is becoming widespread, we could see a lower rate of positive test results simply because of improperly taken swabs.

bacardiandlime

Quote from: pigou on June 17, 2020, 06:10:49 AM
Quote from: Bonnie on June 17, 2020, 05:09:13 AM
They hand you the swab (with their gloved hands, gloves that are changed after each test), you hand it back.
That seems like an awful way to do it. A proper sample requires you to stick that swab WAY up your nose and I can't imagine doing that to myself. If this is becoming widespread, we could see a lower rate of positive test results simply because of improperly taken swabs.

that's my concern too, about self-admin or mail-order tests. No way ANYONE is jamming that swab all the way back on themselves.

Bonnie

Quote from: pigou on June 17, 2020, 06:10:49 AM
Quote from: Bonnie on June 17, 2020, 05:09:13 AM
They hand you the swab (with their gloved hands, gloves that are changed after each test), you hand it back.
That seems like an awful way to do it. A proper sample requires you to stick that swab WAY up your nose and I can't imagine doing that to myself. If this is becoming widespread, we could see a lower rate of positive test results simply because of improperly taken swabs.

Self-administered tests have been happening for over two months now. And yes they are widespread. The accuracy is not as high as the deep nasal medical professional administered test, but is considered to have a high enough accuracy to be useful. You get some coaching. A friend of mine had the technician tell her to insert it again because she didn't look at all uncomfortable.