Daily numbers, graphs, analysis thread 10

[BigChocFrenzy]

Welcome to thread 10 of the daily updates.

Resource links:

Worldometer UK page
Financial Times Daily updates and graphs
HSJ Coronavirus updates
Johns Hopkins Coronavirus Resource Centre
NHS England stats, including breakdown by Hospital Trust
Covidly.com to filter graphs using selected data filters
ONS statistics for CV related deaths outside hospitals, released weekly each Tuesday

We welcome factual, data driven, and civil discussions from all contributors 💐

Some information about asymptomatic versus presymptomatic and transmission on page 2 of WHO guidance:

www.who.int/publications/i/item/advice-on-the-use-of-masks-in-the-community-during-home-care-and-in-healthcare-settings-in-the-context-of-the-novel-coronavirus-(2019-ncov)-outbreak

The virus that caused the 1918 flu pandemic is still with us today, but we have learnt to live with it. Although estimates vary about 20% of flu infections are asymptomatic:
www.ncbi.nlm.nih.gov/pmc/articles/PMC4586318/

Basically more research is needed as to whether T cells can give any sort of immunity after infection there is evidence on both sides, but at least some partial immunity is probable. Cross reactivity may also help but again more research needed.

www.cell.com/cell/pdf/S0092-8674(20)30610-3.pdf

Anything to say if some type / degree of immunity remains for those reported Twins cases where antibodies disappeared so quickly ?

since it is less likely that T cells were involved

I find the concept of a asymptomatic infections confusing.
As I understand it when there is an asymptomatic infection then this means that a person is host to a virus but the virus causes them no ill effects, is this not another way of saying that the virus is pathogenic to some people but not pathogenic to others?
We are all hosts to to numerous and uncountable microorganisms which do not cause us I'll effects but we do not consider them to be infections.

would it be true to say that covid-19 is a virus that some people are able to exist symbiotically with but for others the virus is highly pathogenic?

@B1rdbrain Symbiosis usually means both organisms benefit and it is a relationship.

With virus it is more of an arms race. However the virus obviously wants the host to survive long enough to be able to replicate and spread.

With asymptomatic infections there will be changes but at a cellular level - for example if you cut yourself you are not aware of the anti infection process unless it is overwhelmed and the cut becomes septic.

whats
are you saying that asymptomatic people do have symptoms/ill-effects from the virus but we just don't notice them?

@BigChocFrenzy T cells are part of the first line of defence and involved in the eventual production of antibodies, so will be triggered.

@B1rdbrain, there will be changes but they will be at a level we don't notice. The term symptoms usually refers to things like temperature, headache, etc etc but these are not present. However when changes in biochemical markers such as interleukins are measured there are noticeable differences in those exposed. As you said earlier we are constantly exposed to pathogens and this sort of change is part of life.

My dh and son had quite bad doses of covid-19. My daughter and I were living with them in our average sized 3 bed 1 bathroom house throughout and didn't show any symptoms other than a mild sore throat, and mildly upset stomach (just me).

I should think we would be an interesting family to test for antibodies as I don't believe for one moment we could have avoided getting this infection at home. We didn't do any distancing within the house other than not sharing towels and I didn't sleep in the same bed as my husband after his symptoms came out. He was ill for about 3 weeks, my 16 year old son for about 10 days.

@BigChocFrenzy

I’ve been following these threads and really do appreciate your balanced wisdom.

I wonder if this is something you may be able to please assist with? I am looking to find the demographics of the shielded group. I’m aware there are approx 2 million and I believe this includes 90,000 children but I was wondering where I might find the breakdown of age, sex and employment etc. Thanks in advance.

@haenow This is what the NHS have released about the shielding group - it has age (though 0-18, 19-69,70+), gender and location.

digital.nhs.uk/dashboards/shielded-patient-list-open-data-set

Thank you @patriciaholm :)

B1

I suppose with some viruses it's possible to have it and have no symptoms but still be immune and have antibodies. So for example, some vaccines do this.

If your body can resist the virus entering too many cells and multiplying and then streaming out, to infect more cell then with antibodies that match it and are able to stop it entering cells, you fight it off quickly but it just doesn't trigger a physical immune reaction such as a fever.

I think...

There was a documentary on bbc iPlayer just about viruses and the biology of them which explained how they work and how antibodies might stop a virus entering a cell.

For example, wart and verruca viruses are around all the time; it's how our immune system reacts or not to them.

Severe verruca outbreaks are linked to immune system issues.

We have symbiosis with bacteria and fungi in our guts. I'm not sure we do with viruses. They are essentially parasites of sorts.

virus infections can be linked to cancer though.

The virus that caused the 1918 flu pandemic is still with us today, but we have learnt to live with it. Although estimates vary about 20% of flu infections are asymptomatic

My reading of that article is that the estimates of asymptomatic infections vary very widely and there’s no consensus, with some studies showing rates up to 86%. Also, influenza may still be around, but not the precise variation that caused Spanish Flu.

@ShootsFruitAndLeaves May I ask. What you say about us noticing if numbers begin to go back up so no second wave. IF the easing does indeed send the numbers back up or autumn/winter causes them to go up what will we do to surpress them again?

It doesn't seem likely that the government would go for another lockdown or would they?

Would appreciate your thoughts

Every time a virus infects a host it replicates using the RNA (?) within what ever cell it manages to get into. So it steals little copies as it then gets passed on.

That how they know it's mostly bat and then pangolin and that we mostly got it from the EU. Those Italian ski trips...

A nice little leaving gift, eh? 🎁

So the Spanish flu has been through hundreds of people. Iirc, it mostly killed younger people as a lot of older people apparently had some immunity from a similar strain?

Coronavirus came to UK 'on at least 1,300 separate occasions' www.bbc.co.uk/news/health-52993734

Also wondering. If you have it asymptomatically and then you were exposed again. Would you respond the same way? So even if you’re not immune you are
just not susceptible to the virus?

So potentially you have a huge % who may carry but have no symptoms. Then those who do get it with symptoms build immunity. This all helps reduce the spread? Plus you need less % for herd immunity?

Also wondering. If you have it asymptomatically and then you were exposed again. Would you respond the same way? So even if you’re not immune you are just not susceptible to the virus?

I’m not sure. I wouldn’t be surprised if someone could have sufficient natural immunity to fight off a low infectious dose asymptomatically and not require antibodies, but when exposed again to a higher infectious dose be unable and become symptomatic, especially if run down through tiredness or stress.

I’m thinking t-cells provide protection rather than immunity... protection that may be enough in favourable circumstances, but still leaves you susceptible if not. I may well be wrong - I’m no expert.

However, to follow on from that, it might be possible with enough data to estimate what proportion of the population able to fight of typical infectious dose of Covid, even if individuals do not have natural protection that is effective in all
circumstances.

That proportion could potentially be higher or lower depending on our behaviour and practices as a society. For instance, a society that was both tactile and continued to interact socially when symptomatic, would have a lower level of natural immunity than a society (of similar demographic make up) that wasn’t tactile and tended to withdraw once symptomatic. In one there would be lower viral loads than the other, and more people would be able to fight off infection naturally.

For instance, a society that was both tactile and continued to interact socially when symptomatic

It could be argued that the work ethic and sociability of Lombardy was one reason for why they were so affected.