COVID-19 technical discussion

sudzs wrote: »

Also out of my depth!

Everybody is out of their depth on this one!

There seems to be a lot of variability in the severity of this disease, from extremely severe and needing hospitalisation to extremely mild and having hardly any symptoms at all.

That is the case with many infectious diseases, e.g measles is usually mild but can have serious complications and even be fatal in some cases.

I'm wondering what could be the contributing factors to this variety in the severity of the illness. Could it just be how much of the virus someone is exposed to? Is it differences in individuals immune systems? Or could it be that some people have some sort of 'semi-immunity' to it as a result of previous infections with another coronavirus, possibly one closely related to covid-19??

Probably all of the above and many other factors we aren't aware of. Age and pre-existing conditions, especially hypertension and obesity, look at this very early stage to be important. There is also in most conditions a random element or what could be termed sheer bad luck.

^^^^^^^^^^^^

what does it implicate? there's a link in blood type and severity of infection?

A couple of good podcasts:

This Week in Virology
https://www.microbe.tv/twiv/
This is a very long-running podcast that has turned itself over to COVID-19 recently, and does a couple of long episodes a week, with interviews with coronavirus experts, immunologists, physicians.

A more recently-launched second podcast hosted by the same main presenter, this time focusing on immunology:
https://www.microbe.tv/immune/
The last two episodes have dealt with immunology of COVID-9

They cover many different scientific aspects of the pandemic - virology, immune response to the virus, immune pathology seen in severe cases, PCR & serological testing, vaccines and more - and review the papers being rushed out during the pandemic, and the evolving clinical treatments.

darjeeling wrote: »

A couple of good podcasts:

This Week in Virology
https://www.microbe.tv/twiv/
This is a very long-running podcast that has turned itself over to COVID-19 recently, and does a couple of long episodes a week, with interviews with coronavirus experts, immunologists, physicians.

A more recently-launched second podcast hosted by the same main presenter, this time focusing on immunology:
https://www.microbe.tv/immune/
The last two episodes have dealt with immunology of COVID-9

They cover many different scientific aspects of the pandemic - virology, immune response to the virus, immune pathology seen in severe cases, PCR & serological testing, vaccines and more - and review the papers being rushed out during the pandemic, and the evolving clinical treatments.

Been listening to TWIV for sometime. Absolutely love it. Highly recommend episode 599 with that lady who worked on Ivermectin for Merck. Fantastic information from possibly one of the best placed sources on the subject matter.

amandstu wrote: »

I heard that dementia seems to be one of the most important underlying conditions affecting mortality (or severiity of outcome).

I wonder why that might be? Could it just be that symptoms are treated at a later stage since those patients would less likely to communicate their ongoing symptoms to their careers as promptly as would the general population?

Or would dementia lead to a general lack of physical resilience that would weaken their defences?

Dementia patients are vulnerable and some of the most difficult to protect. They don’t understand the situation, the need for social distancing, the importance of washing your hands. They don’t know why everything is closed and their routine disrupted which in itself worsens their condition.

Sending some into hospital when they can’t be accompanied by a family member or familiar carers would be a cruelty so difficult choices have to be made.

lozenges wrote: »

It tests positive for bits of SARS -CoV-2 virus particles essentially. (SARS -CoV-2 is the same to me as Covid-19, but anyway)

SARS -CoV-2 is one of a family of viruses called coronaviruses. The test only tests for that one kind of coronavirus, but not the other kinds in the family.

Hope that makes sense

The Randox VRI test for the Vivalytic platform test for the following in one hit, but it’s a POC platform so takes 2.5 hrs to do one sample.

• SARS-CoV-2 (COVID-19)
• Sarbecovirus (SARS, SARS like, SARS-CoV-2)
• Influenza A
• Coronavirus 229E/NL63
• Adenovirus A/B/C/D/E
• Influenza B
• Coronavirus OC43/HKUI
• Enterovirus A/B/C
• Rhinovirus A/B
• Middle East Respiratory Syndrome Coronavirus (MERS-CoV)

Most other SARS-CoV-2 tests are specific to that particular virus, and can run a batch of 94 samples plus 2IC in one go.

I'm not a scientist but this may be of interest to the discussion, quick summary, the Chinese identified 30 different strains with hugely different viral loads, hit download PDF to get the full report.
I know it's not peer reviewed but still maybe noteworthy considering it's from China

https://www.medrxiv.org/content/10.1101/2020.04.14.20060160v1.full.pdf+html

What's the feeling if correct, does 30 strains make a possible vaccine a lot more difficult to create?

https://www.cdc.go.kr/board/board.es?mid=a30402000000&bid=0030&act=view&list_no=367267&nPage=1

Very interesting observations here regarding reinfection, repositives and quite interestingly no observation of secondary spread in those cases.

I would be quite interested to know if this is observed elsewhere.

amandstu wrote: »

This is a study posted by someone on the main thread.

https://www.thelancet.com/journals/l...354-4/fulltext

Can someone who is au fait with this kind of stuff have a look at it and explain the findings.

What is defined there as the viral load ?

Is it the population of infected cells in the individual nasal passage at the time of the test?

How does that correlate to the amount of virus that individual was initially infected with,?

And how did morbidity rise as a function of the viral load ?Linearly ?

Presumably not linearly but what kind of exponential relationship was found?

LINK IS BROKEN

Viral load is the amount of virus particles within you body, the virus then replicates by invading cells damaging them and budding producing more virus.

If your initial viral load is high then you will have more virus all replicating at the same time, by the time your body starts to fight the infection it can be overwhelmed by cell damage.

If you have a low initial viral infection then the damage is more limited, if your immune system can kick in to fight the infection before it gets too out of hand.

Front line workers like Doctors and nurses are at risk of being infected with higher loads as they work in an environment where there is a high level infection by multiple sources (patients).

PPE does not prevent infection 100% but it helps reduce the risk and the amount of virus they absorb.

Here is an interesting hypothesis based on the idea that other coronavirus infections may provide protection against Covid-19

https://www.bbc.com/news/world-africa-53998374

Too much hygiene?

I never get colds.**I am less reassured on that score now.

**a lie ; I did get an odd cold in Feb.