Are we any closer towards understanding why some people get so ill ?

[SirVixofVixHall]

I realise that there is variation with all viruses, but with Covid it seems so extreme and unpredictable. Other than knowing that people over a certain age are more likely to die, as are those with some specific health issues, it still seems a mystery.
Many elderly people will not be seriously ill, and some people in the thirties will die. Some people become extremely ill yet others not at all .
I find it frightening, mystifying and yet also interesting. I did read that people with certain blood groups were more likely to have serious illness, but I am not sure how accurate this was.
I imagine scientists around the word are looking at this, so has there been any more light shed ?

I had COVID over Christmas, tested positive during community testing. In my 50s, slightly overweight, asymptomatic. I really think they should be researching this more thoroughly - I.e. if you’ve tested positive maybe a month later having to answer questions about symptoms. This could be done as part of the Covid app surely, then they’d have loads of information at their fingertips and might start seeing patterns.

I would also like to see some studies being done on this!

Some factors that are being studied -
Obesity/poor metabolic health
Low vit D levels
Different blood groups
The neanderthal gene
Biological sex.

I think they’re really missing a trick here. When I was positive I was contacted a few times by the NHS to check up on me etc, they could easily have taken that information then too. If 60,000 odd people a day are testing positive currently then that’s a wealth of information to be had right there.

I'm part of a study looking into this: GENOMICCs. It was published in nature in December. We are taking blood samples from critically ill covid patients and analysing their genes to look for why it affected them so badly. It's ongoing but we have found some genes so far. We need large scale RCTs before we can translate this into clinical practice but rest assured thousands of people are working on this.

It's nationwide so the numbers are huge going into it currently

This is something that interests me as well.

I had a mild case. My BMI is over 40.

DH much slimmer and fitter than me got hospitalised.

We have both taken high doses of vit D for a whole year.

I am O neg and he is O positive.

Covid is very random about who it takes down.

It could be viral load? DH got it first then passed it to me and the kids so maybe we got a lower viral load.

Especially where some family members in same households have been badly affected but others have not.

I also think it's not a rocket science that virus multiplies in the throat, I mean where else could it multiply, just sitting on the door handles? Even in Petri dish it probably needs feeding with something and plenty of that on mucus membranes.

I expect it's more airborne than they let us believe initially hence the need for outdoor masks now being suggested.

I have a theory it’s viral load. So much has been made of hand washing and touching things but if you are breathing in air that has a high viral load then you will be exposed to more of the virus and become sicker. The let fresh air in addition to hands face space is not stressed enough IMO.

Male Vs female severity I can just about understand: females have more genetic material XX vs XY so it could be that that extra genetic material covers immunity (and survival), but it doesn't quite explain long covid.

I agree, test and trace people should capture more data!

@yuyubooboo

I'm part of a study looking into this: GENOMICCs. It was published in nature in December. We are taking blood samples from critically ill covid patients and analysing their genes to look for why it affected them so badly. It's ongoing but we have found some genes so far. We need large scale RCTs before we can translate this into clinical practice but rest assured thousands of people are working on this.

So fascinating ☺️

Viruses don't feed on anything @YogaLite. They can only multiply inside a host cell, they can't actually replicate themselves, they get the host cell they have infected to replicate the virus.

They attach themselves to a cell by binding with a receptor molecule on the cell surface (in the case of SARS-CoV-2, the ACE2 receptor). Then they fuse with the cell membrane or inject their genetic material into the cell so the host cells make copies of the virus. That's a rather simple explanation. This is a more detailed explanation but still easy to follow:

www.khanacademy.org/science/high-school-biology/hs-human-body-systems/hs-the-immune-system/a/intro-to-viruses

Makes sense, thank you @orangenasturtium
I guess that implies that they go for cells with thin/mucosal/broken membranes and wouldn't multiply on say, door handles.

I would also be interested to know how immunity is assessed eg whether it's people with more t-cells or some other cells are the ones NOT getting covid.

But I don't think anyone has ever been tested for immune cells unless ill already with something else.

@orangenasturtium, so (simplifying the matter) am I right that the virus effectively uses something like a (protein) velcro hook to invade the host cell?

@SandysMam

I have a theory it’s viral load. So much has been made of hand washing and touching things but if you are breathing in air that has a high viral load then you will be exposed to more of the virus and become sicker. The let fresh air in addition to hands face space is not stressed enough IMO.

Viral load is certainly very relevant in how ill a person gets. This is why outdoor exercise is not the cause of virus spread, but any indoor mixing is. The government need to redirect policing from people exercising outside towards unnecessary indoors activity, such as non-essential shops/offices/hospitality. Currently we are at risk of having our exercise restricted while Starbucks/fast food staff continue to have to work indoors etc so someone can have a coffee, takeaway etc

This is why outdoor exercise is not the cause of virus spread,

Is there evidence for this? Especially the new variant?

I think it's not about outdoor exercise per se, it's more about how busy areas are, obviously it would be worse indoors but I reckon there is also a risk outdoors in busy areas.

@lavenderlou

This is why outdoor exercise is not the cause of virus spread,

Is there evidence for this? Especially the new variant?

There certainly is no evidence to the contrary. No evidence at all that outdoor exercise spreads covid-19.

@YogaLite

I think it's not about outdoor exercise per se, it's more about how busy areas are, obviously it would be worse indoors but I reckon there is also a risk outdoors in busy areas.

Which is why travelling up to 10 miles for outdoor exercise (as permitted by the Guidance: 'you can travel within your local area') makes sense to avoid exercising on crowded narrow pavements. Yet the police are preventing people travelling short distances to find quiet open spaces away from other people for their exercise, which is actually encouraging overcrowded pavements in urban areas.

And re evidence for outdoor exercise NOT spreading coronavirus - you don't find evidence to prove a negative, you prove a positive. So unless there is clear evidence that outdoor exercise does spread the virus, it should continue.
Certainly while indoor mixing is still allowed, even unnecessary mixing in hospitality venues, and this has been proven to cause virus transmission.

@YogaLite That's correct, viruses can't multiply on a door handle or anywhere other than inside cells of a living organism.

so (simplifying the matter) am I right that the virus effectively uses something like a (protein) velcro hook to invade the host cell?

It's more like the cell has a receptor that is a certain shape and the virus has a bit that fits into that shape instead of the molecule that the receptor is supposed to attach to Sorry, I know that is a rubbish explanation...

I should have said, that's why the virus can only infect certain types of cell that have a specific receptor, not all cells.

New major study starting (Leicester Uni) looking at ethnicity. It will involve large numbers of healthcare workers from all sectors. Using healthcare workers since they are probably more likely to answer regular questionnaires and a good diverse cross section of population.

@Ozzie9523

I had COVID over Christmas, tested positive during community testing. In my 50s, slightly overweight, asymptomatic. I really think they should be researching this more thoroughly - I.e. if you’ve tested positive maybe a month later having to answer questions about symptoms. This could be done as part of the Covid app surely, then they’d have loads of information at their fingertips and might start seeing patterns.

Yes this would be interesting, to see patterns emerging - perhaps then treatment would improve.

yuyubooboo how amazing to be working on something so important.
I am curious as I know a couple where the very fit wife, 40, was unwell (not hospitalised) but her DH who is ten years older , slightly overweight, less fit, had no symptoms at all, he just didn’t appear to catch it.
Same with another couple we know in their forties, where both are healthy and a healthy weight, but she has long covid and he was fine.
It is possible that Dh had covid early on, although he has no antibodies. If so he was the illest I have ever seen him, but at a bad flu level, and I (older, fatter, autoimmune issues) was fine. However in our case we just don’t know and it could have been a different virus.