Virus: Does anyone happen to know whether freezing/refrigerating...

[LAS14]

... will lengthen or shorten the life of a virus particle? When I grocery shop I leave everything in the bags for a couple of days except the stuff I need immediately and stuff that needs cooling. After unpacking, I wash my hands. But I'm wondering if I should leave the stuff out of the refridgerator as long as possible.

Pretty esoteric, I know. But maybe there are some virologists on DU? I know there are a bunch of really smart people.

tia
las

[cwydro]

1. You'd be better off looking to your county or state health departments. Or the CDC.

People are posting an awful lot of nonsense here as though it were true.

[LAS14]

3. I don't think either place is getting down to this level of granularity. And it's...

... not a critical bit of info.

[ProfessorGAC]

2. Just An Opinion Here

Not a virologist, but a retired scientist who has worked with micro experts, so...
I doubt it has much effect to freeze or not.
Virus exhibit signs of life due to their ability to chemically interact with live cells. When their not reproducing, stealing enzymes from healthy cells, they're more a glob a various chemical structures. I would assume ( on the side of caution) that low temperatures, other than perhaps cryogenic, just keep the virus dormant.
Like I said, I understand the chemistry of killing viruses, but am not an expert on them.

[LAS14]

4. Thanks. It's helplful info. Now that..

... I have a better understanding of why a virus dies, I think I'll leave not frozen stuff out of the fridge for several hours. Oh... well... on further reflection it's probably only keeping out of the freezer that could conceivably make a difference... And that has it's own problems. So I guess I'll stop thinking about it.

[ProfessorGAC]

9. A Bit More

On the killing them thing...
The reason why alcohol or disinfectant wipes work are their effect on the protein body of the virus.
Alcohol works by helping to denature enzymes from skin cells and without those enzymes the virus can't reproduce. Also, IIRC the alcohol solubilized the lipid sheath on the protenaceous elements, allow oxidation, so the protein isn't all protein anymore.
Wipes work because there is active labile chlorine ions that can denature the protein and cleave the nucleic acids in the RNA. I can also envision an mechanism to attack on the ribose itself, which could(!) destroy RNA, too.
Again, not an expert on viruses, but did quite a lot of work on the reactions of things used to kill them, so I worked with experts of the viruses themselves. I learned a decent amount from those folks.

[LAS14]

17. Neat! nt

[Big Blue Marble]

5. This study seems to verify what I have read.

The virus does well in the refrigerator

https://www.researchgate.net/publication/41943627_Effects_of_Air_Temperature_and_Relative_Humidity_on_Coronavirus_Survival_on_Surfaces

Have found any data on freezing.

[Igel]

14. It'll be the same trend.

Heat increases the ease with which chemicals react. More molecules reach activation temperature and it's all about cutting molecular bonds and disrupting the protein casing the DNA or RNA is sheathed in. It's why UV lights are good--proteins just love to chow down on photons with energies in the UV part of the spectrum.

If you reach a high enough temperature, the proteins destabilize without needing to interact with anything else, but those are going to be far above body temperature.

Lower temperatures reduce the average energy, and so the viral capsid is more stable and lasts longer.

Freezing is just colder. It's not like the already solid capsid is going to get restructured. And freezing destroys a lot of larger scale structures by having the water in them form crystals; viruses don't contain water and would just get pushed around a bit as crystals formed.

Humidity also matters because the water does interact with the capsid. After all, proteins have dipoles and water has a dipole, and the result is that the proteins can be hydrolyzed (which just means "water-split&quot . While refrigerators may have relatively high *relative* humidity, part of what they do is reduce the absolute amount of water in the air.

That means not only is there less energy to help the capsid's proteins react with oxygen or water, there's less water there for the proteins to react with.

(This, IMHO, is pretty much what any current high-school student who passed freshman biology and sophomore chemistry should be able to say. At least Texas standards require discussing virus structure and types, proteins and capsids, and activation energies. Not sure about the details of hydrolysis. Whether they do, and whether the kids actually pay attention ... Different story.)

How much more stable any given virus is depends on the actual protein structures present, and that's going to need to be evaluated on a virus-by-virus basis.

[Big Blue Marble]

16. Thank you.

This is helpful information.

[samnsara]

6. well it got down to 11 degrees where I am and that didnt stop it...a have a friend who..

..said she was happy as the warmer weather (soon) would kill the virus. I looked at her and said its 80 in Florida and they are still getting it. I think the virus is experiencing every temp variation on Earth right now and its not stopping.

[bamagal62]

7. I wash anything I can with soap and water

before putting it away. If it's cardboard (like cereal) I wipe it down with a chlorox wipe.

[flying_wahini]

8. I read that CV-19 can live up to 6 days on a dry surface.

That’s under ideal conditions.

[consider_this]

10. WASH everything!

Since I also could not have an answer to the same question you had - here is how I handled things when I returned from shopping last week.
Anything that needed to be refrigerated or frozen - I made a very concentrated solution of dishsoap and water, and washed each item with paper towels soaked in said solution. let it sit on the package a short time, then wipe off with wet and dry paper towels. I also washed my bananas and avocados in the soapy water.
I did this on top of garbage bags spread out on my washer and drier in mud room and got rid of those bags after - just in case of any spread.
Anything not needing cooling went straight to the basement (wearing latex gloves) then hands washed. I want to let those items sit at least 10 days (esp the glass and metal containers) My orders in the house are, if you need something from there sooner (so far the demand here was potato chip bags, beer! - you go down with a Clorox wipe or other cleaner and wipe it down - then wash your hands.

DO NOT leave frozen things out like you were saying - you could get ill from a slight thaw.

[Igel]

15. And that can be a problem.

I mean, yesterday I made salad.

I did not wash everything separately for at least 20 seconds with soap and water. Some things got peeled, but even then I thoroughly rubbed everything from the unpeeled portions into the peeled portions as I worked.

[DetlefK]

11. Viruses are pretty much immune to cold temperatures.

Freezing will kill bacteria, but not viruses. They are small and sturdy bastards.

[OregonBlue]

12. I keep a small bucket of water with dish soap and a bit of bleach

In the kitchen. Everything that comes into the house gets wiped down and allowed to dry a few minutes. All my produce is being soaked in a mild water and bleach solution and then rinsed and allowed to drip dry before I put it away.
Every morning I'm wiping all the door knobs, kitchen cabinet handles, faucets, refrigerator handles, etc. down. If you keep a bucket handy at all times, it's pretty easy.
After a while it just becomes routine.

[BusyBeingBest]

13. I haven't gotten this paranoid yet--

I doubt there are more than a relative handful of people who have handled any grocery items you bring home. If someone touched your cereal box last week with a virused hand, the virus would probably be deactivated by the time you touched it. And the virus isn't replicating itself all over the package, it's not like bacteria multiplying itself. I will Clorox-wipe off milk bottles and other refrigerated items because I feel that's the CV's best chance to stay viable (chilly and damp), but as far as freezer and pantry items, nah. I just wash my hands several times during food prep, throw packaging away, wash up again right before sitting down to eat.

[LAS14]

18. What about all those people gazing at the shelf and breathing on it? nt

[BusyBeingBest]

19. Meh. Even if some virus particles

landed on your packages, AND those particles are viable, as long as you aren't rubbing your hands all over the packages and sticking your fingers in your eyes/nose/mouth, you probably won't get sick. Wash your hands after handling packaging, throw outer packaging away, don't stick your fingers into your face-holes, you'll probably be fine.

[LAS14]

20. Once I get home I can't count on not touching my face, never mind not eating..

.... food I've prepared. So after I wash my hands I want to be reasonably sure about not contaminating them again.

[BusyBeingBest]

21. If it makes you feel better, go ahead.

I just don't happen to believe that random objects brought into the house are going to be a likely way to contract an illness. Staying away from other people, and not touching communal surfaces in public, and hand washing, will probably be effective for the vast majority of folks. I have to draw boundaries on how much to worry about it for my own sanity, and so do you.