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Fomites

Posted: Mon Oct 12, 2020 1:15 pm
by Brightonian
From this Bloomberg piece, "SARS-CoV-2 has been found to persist longer on smooth surfaces".

I'd been meaning to ask for a whole about how robust those findings of "1 day" on paper and cardboard, "3 days" on steel and plastic, and so on were (those findings were from 7-8 months ago I think). But now there's this suggestion that the virus can last a whole lot longer. Should I change my practices on how long I quarantine groceries etc.?

Re: Fomites

Posted: Mon Oct 12, 2020 1:37 pm
by Gfamily
Worth noting that the process seemed to have been designed to maximise viability
It involved drying the coronavirus in an artificial mucus on different surfaces, at concentrations similar to those reported in samples from infected patients, and then re-isolating the virus over a month. The study was also carried out in the dark, to remove the effect of ultraviolet light, as research has demonstrated direct sunlight can rapidly inactivate the virus.

Re: Fomites

Posted: Mon Oct 12, 2020 1:51 pm
by Martin Y
It does make one wonder how to treat fresh and frozen items when cool temperatures seem to preserve the virus as well as the food.

It does reinforce my view that stuff which can take a bit of heat can be decontaminated pretty quickly if you have a hot place to store it. At work there's been a lot of dithering over whether it's best to clean equipment between uses with alcohol wipes or with soap and water (for stuff like foam windshields from microphones) or maybe with UV, but I've been saying all along the simple answer is a sauna-hot store room or cupboard that stuff can just be left in overnight.

Re: Fomites

Posted: Mon Oct 12, 2020 2:50 pm
by jimbob
We seem to have started concentrating on aerosols, but we do know from New Zealand that these are still potential problems:


https://www.rnz.co.nz/news/national/427 ... -infection
The Ministry of Health has identified a rubbish bin as the probable source of a recent Covid-19 case - a similar event to the case of a worker in Auckland who was infected by a lift button.
And cool, dark, damp areas that preserve organic material tend to prolong the viability of the virus.

Re: Fomites

Posted: Mon Oct 12, 2020 3:06 pm
by headshot
We're still washing all of our groceries and quarantining packages etc, etc.

It's tedious, but so what?

Re: Fomites

Posted: Mon Oct 12, 2020 6:27 pm
by FlammableFlower
jimbob wrote:
Mon Oct 12, 2020 2:50 pm
We seem to have started concentrating on aerosols, but we do know from New Zealand that these are still potential problems:


https://www.rnz.co.nz/news/national/427 ... -infection
The Ministry of Health has identified a rubbish bin as the probable source of a recent Covid-19 case - a similar event to the case of a worker in Auckland who was infected by a lift button.
And cool, dark, damp areas that preserve organic material tend to prolong the viability of the virus.
I know it's off-topic and rather insensitive, but that makes me think of the Golgafrinchams from The Hitchhiker's Guide to the Galaxy...

Re: Fomites

Posted: Mon Oct 12, 2020 8:25 pm
by Trinucleus
FlammableFlower wrote:
Mon Oct 12, 2020 6:27 pm
jimbob wrote:
Mon Oct 12, 2020 2:50 pm
We seem to have started concentrating on aerosols, but we do know from New Zealand that these are still potential problems:


https://www.rnz.co.nz/news/national/427 ... -infection
The Ministry of Health has identified a rubbish bin as the probable source of a recent Covid-19 case - a similar event to the case of a worker in Auckland who was infected by a lift button.
And cool, dark, damp areas that preserve organic material tend to prolong the viability of the virus.
I know it's off-topic and rather insensitive, but that makes me think of the Golgafrinchams from The Hitchhiker's Guide to the Galaxy...
I dont think we're far off the coming of the great white handkerchief

Re: Fomites

Posted: Mon Oct 12, 2020 8:27 pm
by Trinucleus
Gfamily wrote:
Mon Oct 12, 2020 1:37 pm
Worth noting that the process seemed to have been designed to maximise viability
It involved drying the coronavirus in an artificial mucus on different surfaces, at concentrations similar to those reported in samples from infected patients, and then re-isolating the virus over a month. The study was also carried out in the dark, to remove the effect of ultraviolet light, as research has demonstrated direct sunlight can rapidly inactivate the virus.
The BBC modified their original report to say that virus in wet mucus had a much shorter active time

Re: Fomites

Posted: Mon Oct 12, 2020 10:21 pm
by Grumble
headshot wrote:
Mon Oct 12, 2020 3:06 pm
We're still washing all of our groceries and quarantining packages etc, etc.

It's tedious, but so what?
We never started doing that.

Re: Fomites

Posted: Tue Oct 13, 2020 1:07 am
by jdc
There was a bit in the Lancet on fomites and that the other week: https://www.thelancet.com/journals/lani ... 2/fulltext

It's only a wee letter, but there's a bunch of papers referenced if you fancy digging a little deeper.

Re: Fomites

Posted: Mon Feb 01, 2021 12:39 am
by Brightonian
Nature article suggesting sanitising groceries etc. is excessive: https://www.nature.com/articles/d41586-021-00251-4

I do sometimes wonder if occupying the kitchen for half an hour sanitising stuff, getting stressed while I do it, while housemates flit in and out, is worth it.

But with that tiny bit of uncertainty I'll probably just carry on. I'm now got so uncomfortable handling stuff that I haven't personally sanitised or quarantined that I'm becoming a compulsive hand-washer.

Re: Fomites

Posted: Mon Feb 01, 2021 12:51 am
by discovolante
Brightonian wrote:
Mon Feb 01, 2021 12:39 am
Nature article suggesting sanitising groceries etc. is excessive: https://www.nature.com/articles/d41586-021-00251-4

I do sometimes wonder if occupying the kitchen for half an hour sanitising stuff, getting stressed while I do it, while housemates flit in and out, is worth it.

But with that tiny bit of uncertainty I'll probably just carry on. I'm now got so uncomfortable handling stuff that I haven't personally sanitised or quarantined that I'm becoming a compulsive hand-washer.
Me too :( I know it's OTT and I don't expect anyone else to do it, but it's a hard habit to break out of when it's such an easy step to take. I was always a bit that way inclined (although somehow managed to put the habit on ice when camping, somehow). Although rather than sanitize, more often I just leave stuff for a few days if I can, or wash my hands immediately after touching if not, and so on.

Re: Fomites

Posted: Mon Feb 01, 2021 1:08 am
by Nickynockynoonoo
headshot wrote:
Mon Oct 12, 2020 3:06 pm
We're still washing all of our groceries and quarantining packages etc, etc.

It's tedious, but so what?
Same here except for frozen then it's a pain in the neck when I take stuff out of the freezer. I have learned to put packet on the baking tray to save cleaning the work surface. Some things can be opened with one hand leaving the clean hand for opening the freezer again. I can even open the bin cupboard with my foot now!

ETA Tongs are handy for post and fliers. Saves at least 1 handwash.

Re: Fomites

Posted: Mon Feb 01, 2021 2:27 pm
by Bird on a Fire
We don't normally bother, but things have been so bad here lately that we gave it a go.

Filled the plant sprayer with ~70% ethanol and misted everything, then left it to dry with a fan on. Better than nothing, probably, and no great hardship.

Re: Fomites

Posted: Mon Feb 01, 2021 4:52 pm
by Trinucleus
Bird on a Fire wrote:
Mon Feb 01, 2021 2:27 pm
We don't normally bother, but things have been so bad here lately that we gave it a go.

Filled the plant sprayer with ~70% ethanol and misted everything, then left it to dry with a fan on. Better than nothing, probably, and no great hardship.
I hope you don't smoke

Re: Fomites

Posted: Tue Feb 02, 2021 5:24 pm
by raven
Brightonian wrote:
Mon Feb 01, 2021 12:39 am
But with that tiny bit of uncertainty I'll probably just carry on. I'm now got so uncomfortable handling stuff that I haven't personally sanitised or quarantined that I'm becoming a compulsive hand-washer.
Ever since that Naked Scientist bloke made a joke on TV about not eating packaging and you'll be fine, I've been very consientious about washing hands between opening packets that were in the supermarket less than 3 days ago and eating stuff like crisps ('cos you don't eat them with forks, do you) and salads ('cos you don't cook salad).

I only wash a few things like milk and drinks bottles, which is easy & I started doing because we often get those from the corner shop, where there person on the register has to handle everything to scan it.

And I clean my specs and my phone after I've been to the supermarket... :roll:

Re: Fomites

Posted: Tue Feb 02, 2021 5:59 pm
by Brightonian
raven wrote:
Tue Feb 02, 2021 5:24 pm
Brightonian wrote:
Mon Feb 01, 2021 12:39 am
But with that tiny bit of uncertainty I'll probably just carry on. I'm now got so uncomfortable handling stuff that I haven't personally sanitised or quarantined that I'm becoming a compulsive hand-washer.
Ever since that Naked Scientist bloke made a joke on TV about not eating packaging and you'll be fine, I've been very consientious about washing hands between opening packets that were in the supermarket less than 3 days ago and eating stuff like crisps ('cos you don't eat them with forks, do you) and salads ('cos you don't cook salad).

I only wash a few things like milk and drinks bottles, which is easy & I started doing because we often get those from the corner shop, where there person on the register has to handle everything to scan it.

And I clean my specs and my phone after I've been to the supermarket... :roll:
Oh, cos someone could have breathed on them? Hadn't thought of that. Or just because one handles them? I do sometimes clean my specs post-supermarket as I'm often adjusting them.

But phone...I do remember someone recommending cleaning one's phone but I almost never do that on the grounds that I rarely have my phone out when I'm in the supermarket, but sometimes I do. There was one time a few months ago someone stopped me in the street - he was was looking for a hostel. I try to help people in need, and he claimed he didn't have a phone. I Googled local hostels for him, eventually found one to his liking (I suspect he'd been barred from one or two), even ringing them up to ask if they had a room. While I was doing this he kept edging round to my shoulder, looking at what I was doing, and his mask kept slipping, and him trying to touch my screen. It was a nightmare continually telling him to put his mask up, keep away, and NEIN!! NICHT TOUCHEN MY PHONEN!!! (Thought he was German at first, turned out he was Iranian). I did sanitise my phone afterwards on that occasion.

Re: Fomites

Posted: Tue Feb 02, 2021 6:23 pm
by Grumble
Now I feel weird because I’ve never disinfected deliveries or left them for days or whatever.

Re: Fomites

Posted: Tue Feb 02, 2021 8:46 pm
by Fishnut
Grumble wrote:
Tue Feb 02, 2021 6:23 pm
Now I feel weird because I’ve never disinfected deliveries or left them for days or whatever.
Me neither

Re: Fomites

Posted: Tue Feb 02, 2021 9:12 pm
by discovolante
Well, speaking purely personally, it's not a road you want to go down if you don't feel the need...that said I'm a bit on the fence about it generally being unnecessary; I totally agree that deep cleaning entire rooms between use by the public etc is totally pointless if it doesn't come with good social distancing and ventilation, but as a personal precaution, well it's a bit like what people are saying in the smart motorways thread, the risk may be small but the consequences are pretty rough.

I don't impose my own handwashing/cleaning standards on other people in the house though because I know my personal behaviour is a bit OTT. I get through a lot of soap.

Re: Fomites

Posted: Tue Feb 02, 2021 10:27 pm
by jimbob
discovolante wrote:
Tue Feb 02, 2021 9:12 pm
Well, speaking purely personally, it's not a road you want to go down if you don't feel the need...that said I'm a bit on the fence about it generally being unnecessary; I totally agree that deep cleaning entire rooms between use by the public etc is totally pointless if it doesn't come with good social distancing and ventilation, but as a personal precaution, well it's a bit like what people are saying in the smart motorways thread, the risk may be small but the consequences are pretty rough.

I don't impose my own handwashing/cleaning standards on other people in the house though because I know my personal behaviour is a bit OTT. I get through a lot of soap.
Dad and his former colleagues do. But their first year at M6AFF was dealing with the 1967 Foot and Mouth outbreak, which has made them all paranoid.

That's a truly scary level of infectiousness.

Re: Fomites

Posted: Wed Feb 03, 2021 8:43 am
by shpalman
... a tweet linking to

Coronavirus is in the air — there’s too much focus on surfaces

... which is an editorial linking to Exaggerated risk of transmission of COVID-19 by fomites by E. Goldman in The Lancet. Infectious Diseases, 03 Jul 2020, 20(8):892-893 which is dated July so I don't know why it's coming up now (or if it's not out of date).

Re: Fomites

Posted: Wed Feb 03, 2021 11:15 am
by Fishnut
shpalman wrote:
Wed Feb 03, 2021 8:43 am
... a tweet linking to

Coronavirus is in the air — there’s too much focus on surfaces

... which is an editorial linking to Exaggerated risk of transmission of COVID-19 by fomites by E. Goldman in The Lancet. Infectious Diseases, 03 Jul 2020, 20(8):892-893 which is dated July so I don't know why it's coming up now (or if it's not out of date).
I think it's coming up now because people/authorities are still focusing on surfaces and ignoring ventilation despite much research showing that it is one of the key factors that need to be controlled to prevent transmission. I suspect also, in the summer when people could do stuff outside, ventilation was lower down people's priorities but now that it's winter stuffing people into rooms with the windows closed to keep the heat is being recognised as a Bad Idea.

Re: Fomites

Posted: Wed Feb 03, 2021 6:55 pm
by shpalman

Re: Fomites

Posted: Wed Feb 03, 2021 9:58 pm
by raven
Brightonian wrote:
Tue Feb 02, 2021 5:59 pm
raven wrote:
Tue Feb 02, 2021 5:24 pm
And I clean my specs and my phone after I've been to the supermarket... :roll:
Oh, cos someone could have breathed on them? Hadn't thought of that. Or just because one handles them? I do sometimes clean my specs post-supermarket as I'm often adjusting them.
'Cos I touch them. Have to lift my specs to read labels & best before dates these days. (I also have a terrible habit of sticking specs in my mouth, but I've just about trained myself out of that now.)