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SillyOldDuffer06/04/2020 10:17:11
5633 forum posts
1157 photos
Posted by Nigel Graham 2 on 06/04/2020 00:17:03:

The people who are wilfully and openly flouting what have become laws, have only themselves to blame...

There is though an aspect to it all that the authorities have not considered.

Most of us here are in model-engineering clubs of which many have costly, large-scale physical assets; ...

How does anyone entrusted with any of this property, look after it in these restricted times?

It's hard to see logically why someone local can't pop in with one other (a spouse?) or alone but overseen by a safety contact by telephone, now and again to test smoke alarms, ensure no leaks or vermin, pick up letters, collect wind-blown litter, air the building for a couple of hours.

Yet officially this appears to be an illegal ' non-essential ' act, ...

The purpose of the lock-down is to minimise contact between people. Those who isolate can't catch it or pass it on to someone else. Therefore the less movement the better.

I see three categories of thinking causing people to break the lock-down:

  1. Gormless, contrarian, or ignorant behaviours, like the baseball example. Stupid boy bravado.
  2. The 'Doesn't apply to me' mistake. Prime Minister hospitalised this morning because - somehow - government failed to apply their own social distancing rules in parliament. Possibly Catherine Calderwood fell into the same trap, somehow believing it was OK for her to ignore essential travel rules. Why did a responsible, intelligent, medical professional behave like a silly girl?
  3. Rationalising that a personal interest, like looking after a club or a birthday party, is somehow important enough to be an exception. Though sympathetic to Nigel's concerns I'd rather burn down a dozen clubs rather than risk spreading a fatal virus.

It's very difficult problem to manage. The government are trying to balance the painful measures needed to control a major health crisis against cost and the need to maintain normality. People are dying of the disease while others lose their livelihoods. Hospital, care home and other workers are courageously putting themselves on the line day after day after day. I'm not aware that any club has suffered due to reduced care-taking; surely in comparison to everything else, looking after a club isn't a priority?

Dave

Clive Steer06/04/2020 10:21:28
23 forum posts

I've seen references to Cover-19 being described as a Schrodinger virus.

One state is that one has the virus but possibly not showing any symptoms and therefore could unwittingly infect others.

The other state is that one does not have the virus and therefore have no immunity to the virus and susceptible to infection.

So until tested we both have and don't have the virus.

Clive

Bazyle06/04/2020 10:34:29
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5141 forum posts
199 photos

Re maintenance. It comes back to common sense again. Agricultural workers and utilities maintenance goes on, mostly solitary so no risk unless tools are shared, a gardener friend continues because it is solitary and he doesn't even talk to the property owner directly anyway. We do need people to continue working to pay taxes rather than burden the support system where safe to do so.
So a club facility could be reasonably maintained by a single person but I don't know if picking up litter and airing it are stretching the freedom. It's not like a railtrack needs short grass or flowers. Our Men's Shed has utilities turned off except for alarm and camera with a local doing his daily dog walk going by it and the cricket club has put sheep onto the outfield to avoid having to cut the grass. Partly doing nothing at these locations is helping to show the spirit of the requirement.

Robert Atkinson 206/04/2020 10:39:25
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615 forum posts
16 photos

While walking the dog and getting my exercise yesterday I noticed what appeared to be a young man in he childrens play area. wandering over (no closer than about 15ft) I discovered a man, toddler and obviously pregnant woman on the paly equipment. I pointed out the area as closed and the signs. The Man was totally dismissive, "I'll be alright" clearly no understanding of transmission or care about anyone else. They commented on my being out and I said walking, the dog, exercising, keeping my distance and not touching anything.

I think essential checks on club facilities, if alone and subsituted or combined with that days exercise, is reasonable. Needs to be only ONE member doing it though. If every member checked or there was a rota that is a classic cross contaminaion case.

Robert G8RPI.

pgk pgk06/04/2020 11:27:02
1729 forum posts
287 photos

Window cleaner just rocked up! Wife sent him packing - hardly essential and it's raining at the mo' too.
However one can understand a small self-employed bloke getting into deep do-do's in these times.

pgk

Martin Kyte06/04/2020 11:58:04
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1807 forum posts
33 photos
Posted by Steviegtr on 06/04/2020 00:03:23:

Does anyone know if you buy a frozen item & the packaging is contaminated. When you bring it home & put it in the freezer, does that freeze the virus. Just for it to come back at room temperature. ?????

Steve.

For the last 30 years I have worked in a biological research lab as an electronics designer in support of the science. In consequence I have become familiar with much of the science and many of the safety proceedures around the Lab, that coupled with a personal interest in what we do has given me a reasonable understanding of the issues.

So speaking as an educated amateur rather than a professional biosafety officer, I would reply that:-

The virus capsid (coat) is a number of proteins that together form a closed structure enclosing the genetic material. Protein structures become less stable at increasing temperatures and eventually denature when heated. This is what happens when you fry an egg. When albumen turns white it is denaturing and loosing it's shape. Proteins rely on their shape to be biologically active and loss of tertiary structure prevents them from doing so. Simply put with heat they fall apart to become a disordered string of amino acids. Viruses are routinely frozen in the Lab in order to preserve them for future study. When in a liquid pH is a factor and extremes of pH again the protein structure is lost and with it biological activity. That's why for example bleach works.

With regard to freezing I have read of some concern in the literature regarding melting glaciers/icecaps etc and the possible re-release of ancient virus particals so it is certainly considered a viable scenario.

Unfortunately we all have to eat but I would hold that the trip to the supermarket is the major hazard rather than the items you bring home.

So lastly I would say that although some decontamination can be carried out your best proceedure is to wash your hand very regularly when handling food items, clean surfaces regularly and be aware that cooking will deal with the rest.

I hope this helps. As I say I do not set myself up as an authority but I am perhaps more clued up that the average chap in the street.

Best regards Martin

 

 

Edited By Martin Kyte on 06/04/2020 12:20:20

Michael Gilligan06/04/2020 12:11:45
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15481 forum posts
668 photos

A useful summary, Martin ...Thanks

MichaelG.

pgk pgk06/04/2020 12:26:25
1729 forum posts
287 photos

Feezing stuff for storage is quite an involved procedure. I have no knowledge of current methods but certainly back in the day freezing sperm involved mixing it with egg proteins and being careful about the speed and final temperatures reached and importantly the stability of that final temperature.


A quick google on freezing viruses for storage (which may/may not apply to this specific virus) gave these two quotes:

<<Virus Freezing
However, RNA and most enveloped viruses are extremely heat labile and need to be snap-frozen (frozen rapidly) and stored at -80°C for long-term storage. Please note that most viruses will suffer damage if storage temperatures exceed greater than -60°C. 1.>>

and

<<Viruses frozen in water are likely to be inactivated by the water's relatively low pH. ... He adds that viruses are more likely to survive in a frozen state if they freeze and thaw only once, as the freeze-thaw process kills at least 90% of virus each time.>>

Obviously time in the freezer has a big effect as would condensation on the packet before the freeze 'took' So the risk is probably lower than first thoughts would suggest. It;s also worth remembering SOD's comments re postman handling packages... the difference between someone sneezing slime on the enevelope and the relative smaller amount of particles likely to be deposited by the item being put in the letterbox.


Supermarket risk is going to be greatest from all the asymptomatic folk breathing your way and accumulated virus particles from multiple handling of objects - notable the trolley handles (if supermarket isn't cleaning them) check-out belts and card machines.

pgk

Andrew Johnston06/04/2020 12:40:48
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5411 forum posts
627 photos
Posted by Mick B1 on 06/04/2020 09:57:24:

..............some of the rule-breakers probably have PhDs..........

At least I'm not ignorant.

Andrew

J Hancock06/04/2020 13:29:08
391 forum posts

Just out of interest, does anyone know if wiping handles, etc, down with a petrol soaked rag will kill 'it ' ?

Martin Kyte06/04/2020 14:12:33
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1807 forum posts
33 photos
Posted by pgk pgk on 06/04/2020 12:26:25:

Feezing stuff for storage is quite an involved procedure. I have no knowledge of current methods but certainly back in the day freezing sperm involved mixing it with egg proteins and being careful about the speed and final temperatures reached and importantly the stability of that final temperature.


A quick google on freezing viruses for storage (which may/may not apply to this specific virus) gave these two quotes:

<<Virus Freezing
However, RNA and most enveloped viruses are extremely heat labile and need to be snap-frozen (frozen rapidly) and stored at -80°C for long-term storage. Please note that most viruses will suffer damage if storage temperatures exceed greater than -60°C. 1.>>

and

<<Viruses frozen in water are likely to be inactivated by the water's relatively low pH. ... He adds that viruses are more likely to survive in a frozen state if they freeze and thaw only once, as the freeze-thaw process kills at least 90% of virus each time.>>

Obviously time in the freezer has a big effect as would condensation on the packet before the freeze 'took' So the risk is probably lower than first thoughts would suggest. It;s also worth remembering SOD's comments re postman handling packages... the difference between someone sneezing slime on the enevelope and the relative smaller amount of particles likely to be deposited by the item being put in the letterbox.


Supermarket risk is going to be greatest from all the asymptomatic folk breathing your way and accumulated virus particles from multiple handling of objects - notable the trolley handles (if supermarket isn't cleaning them) check-out belts and card machines.

pgk

You are quite corrrect. Indeed our proceedures for freezing samples for Cryo-Electronmicroscopy involves plunging grids into liquid ethane. This not only preserves the folded state of the protein but creates non crystaline ice which doesn't interfere with imaging.

Slow freezing will certainly be much less efficient in preserving virus largely through the crystal formation. However what is in question is not the preservation but the destruction of virus particles and slow freezing cannot really be seen as a way of destroying virus. Some may certainly survive.

I agree with you your trip to the supermarket is the major risk.

regards Martin

John Paton 107/04/2020 23:01:24
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268 forum posts
17 photos

JH, in the absence of authoritative reply to your question, I would suggest 'probably not' - stick to soap which we have been told time and again by the experts is the best method. (it is also cheap and kind to the skin!)

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