New research data on COVID-19 contamination and spread

[KY_EnviroGuy]

We're finally getting some concise scientific info on surface contamination risks and aerosolization for COVID-19!

Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1
The New England Journal of Medicine
March 17, 2020

Read here: https://www.nejm.org/doi/full/10.1056/NEJMc2004973?query=featured_home

Intro:

A novel human coronavirus that is now named severe acute respiratory syndrome coronavirus (SARS-CoV-2) (formerly called HCoV-19) emerged in Wuhan, China, in late 2019 and is now causing a pandemic.1 We analyzed the aerosol and surface stability of SARS-CoV-2 and compared it with SARS-CoV-1, the most closely related human coronavirus.

And, a good Q&A article from The Guardian UK:

How long does coronavirus survive on different surfaces?
Covid-19 RNA was found on a cruise ship 17 days after passengers left.
What are the risks of handling packages and groceries?
Danielle Renwick
Wed 25 Mar 2020 14.54 GMT

Link: https://www.theguardian.com/us-news/2020/mar/25/how-long-coronavirus-lasts-on-surfaces-packages-groceries

Intro:

More people are staying indoors to avoid contact with people potentially infected by Covid-19. But in light of a recent report from the US’s Centers for Disease Control and Prevention (CDC) that said fragments of Covid-19 were found in the Princess Cruise ship 17 days after its passengers had left, what are the risks of handling packages, groceries and what scientists call “high-touch” surfaces?

(Cross-posted to Health).............

[SouthernIrish]

1. Thank you

Very informative.

[msongs]

2. covid 19 is an enveloped virus which means easiest to deactivate. they say nt

[KY_EnviroGuy]

3. Yes, and it was a relief to read....

plain soap and water or ethyl alcohol (high-proof booze) are the most effective neutralizers.

It's unfortunate there's so much misleading info floating around the web and other media, particularly on food safety.

This being a novel virus, it's just taking some time for true scientific research to hit the street.......

[ProfessorGAC]

4. High Proof Booze

Only 151 Rum & Everclear apply. Even most high proof liquors & liqueurs top out at 110 proof. (Dar chartreuse for instance)
The most effective alcohol concentration for microbial kill is 70%, by weight. That around 145 proof.
Now, lower proofs will work, but contact time goes up geometrically as concentration goes down.last, isopropyl alcohol is equally effective on microbes and, since it's non-potable, there's no liquor tax. Way cheaper.

[KY_EnviroGuy]

5. Yes. This is the paper I use as reference you may have seen....

and another good resource to pass along to family and friends:

Interim guidance for environmental cleaning in non-healthcare facilities exposed to SARS-CoV-218
February2020

Scope of this document
This document aims to provide guidance about the environmental cleaning in non-healthcare facilities (e.g. rooms, public offices, transports, schools, etc.) where confirmed COVID-19 cases have been before being admitted to hospital. This guidance is based on the current knowledge about SARS-CoV-2and evidence originating from studies on other coronaviruses.

Link (PDF): https://www.ecdc.europa.eu/sites/default/files/documents/coronavirus-SARS-CoV-2-guidance-environmental-cleaning-non-healthcare-facilities.pdf

If I could afford it, I would prefer Everclear because it's better product for mixing with essential oils than isopropanol for skin applications. But for wiping down hand rails or counters, isopropyl is fine and cheaper. They're saying 50% isopropyl is effective for cleaning, while hand sanitizers use a higher concentration.

For now, my son and I are just using soap and water and spray disinfectants........

[ProfessorGAC]

7. 70% Is The Microbiologists' Go To

Every one of them I've ever worked say that, and the reason why it's best is always the same.
I've seen swab tests after using for 10 seconds and the plates are utterly clean. Plain fortified agar. They seemed to know what they're talking about.
IPA is only barely harsher than ethanol on the doing, for the limited contact time. And just plain hand cream, which are on store shelves is a good way to take care of drying the skin.
Everclear is, by the way, about 8x the cost of IPA.

[KY_EnviroGuy]

8. I believe the European paper's objective was....

to determine the minimum concentrations that are effective, which is good knowledge. Above that level, it's everyone's choice how much margin they prefer. Also consider that much will be lost very quickly to evaporation with hand sanitizers, so more margin of safety is appropriate.

[ProfessorGAC]

13. Lost Me

The paper specifically says that 70% ethanol was the most effective on surfaces where a 1000 ppm hypochlorite was inappropriate.
And, believe it or no, for bacteria, the cooling by evaporation prevents the retardation of respiration. The cooling increases it to maintain the temp in the cell internals. Greater respiration results in faster poisoning.
And, the concern is evaporation reducing contact time, using IPA is a solution. The vapor pressure of IPA is about 25% that of EtOH at 25C.

[KY_EnviroGuy]

14. You're right, sorry. I keep wanting to relate iso to hand sanitizer....

whereas they all use ethyl. Looking at their labels, the ones I have use 70% ethyl.

Very interesting fact you presented on rapid cooling of bacteria. Sounds as if they react like humans do to sudden chills.

[ProfessorGAC]

16. That Cold Thing Only Works For A Very Short Time

After a while, respiration drops to bare minimum. Essentially dormancy.
That's why putting food in the freezer doesn't kill bacteria, but does prevent reproduction.

[LArider]

10. So what you're saying is

that Ms. Newby's hunch punch is the best way to get rid of it? In.

[ProfessorGAC]

11. I Guess

Never heard of that punch.

[LArider]

12. Ms. Newby's

was a big liquor store/bar in Panama City. Don't know if it's still open or not but their hunch punch was 151, everclear and hawaiian punch.

[KY_EnviroGuy]

15. Because you appear to be knowledgeable in this field....

I found this paragraph from the paper interesting and would appreciate your thoughts:

Our results indicate that aerosol and fomite transmission of SARS-CoV-2 is plausible, since the virus can remain viable and infectious in aerosols for hours and on surfaces up to days (depending on the inoculum shed). These findings echo those with SARS-CoV-1, in which these forms of transmission were associated with nosocomial spread and super-spreading events,5 and they provide information for pandemic mitigation efforts.

So much of the press has talked only about disease spread by droplets, I would like to see more discussion on the hazards of aerosols, particularly relating to enclosed habitation spaces such as homes, grocery stores and churches where non-HEPA air filtration is common.

KY

[ProfessorGAC]

17. I Think That's The Point Of Social Distancing KEG.

Studies, including one you can watch by the Mythbusters, show sneezes can send droplets and aerosols 3 or 4 feet.
I think that's where the 6 feet came from.
While it may suggest that aerosolized liquids allow the virus to maintain activity for hours, gravity makes it highly unlikely that they won't fall to the floor or other surfaces in a minute or less.
By the way, an aerosol is a fine colloidal suspension of liquid in air. So, when the doctors are talking droplets, they probably mean both we can see, and the micro sized droplets we can't.

[DeminPennswoods]

6. Thanks, good info

nt

[LAS14]

9. Thanks! This is definitely one of the most helpful articles I've seen.

I do like the Guarian. Every now and then I respond to their pop-ups for donations, even though they're for-profit. There was none associated with this article, though.