SARS-CoV-2 Coronavirus (COVID-19)

Speculation: I wonder if anyone diagnosed with COVID-19 automatically has aggressive contract tracing with the Public Health department. In effect, treat their family, neighbors, and co-workers as primary candidates for COVID-19 contact tracing. Include assertive flyers and education ... spend time to get the most likely tested and educated.

Bob Wilson

 

I find the vegetative nature of the Dakotas amusing. <SMILES>

Bob Wilson

 

new hampshire has now opened vaccinations to any non residents

 

'billings montana reports 75% of vax appointments are open'

 

And now North Dakota is vaccinating Canadians (Manitobans) who having been regularly crossing the border as essential workers.

Considering the comparatively slow vaccine rollout in Canada (similar to most countries that don't possess the vaccine factories), and much of the U.S. now having many appointment slots going unfilled, the other border states should consider doing this too.

 

My university, Fairfield U in CT, is providing on-campus vaccinations today. Maybe a call to each of your kid's schools would help.

JeffD

 

except michigan

 

Not a very surprising result. But it is now official that the saliva of infected indivisual can spread the COVID-19.

Study Demonstrates Saliva Can Spread Novel Coronavirus; NIH Director's Blog

COVID-19 is primarily considered a respiratory illness that affects the lungs, upper airways, and nasal cavity. But COVID-19 can also affect other parts of the body, including the digestive system, blood vessels, and kidneys. Now, a new study has added something else: the mouth.

The study, published in the journal Nature Medicine, shows that SARS-CoV-2, which is the coronavirus that causes COVID-19, can actively infect cells that line the mouth and salivary glands. The new findings may help explain why COVID-19 can be detected by saliva tests, and why about half of COVID-19 cases include oral symptoms, such as loss of taste, dry mouth, and oral ulcers. These results also suggest that the mouth and its saliva may play an important—and underappreciated—role in spreading SARS-CoV-2 throughout the body and, perhaps, transmitting it from person to person.

[1] SARS-CoV-2 infection of the oral cavity and saliva. Huang N, Pérez P, Kato T, Mikami Y, Chiorini JA, Kleiner DE, Pittaluga S, Hewitt SM, Burbelo PD, Chertow D; NIH COVID-19 Autopsy Consortium; HCA Oral and Craniofacial Biological Network, Frank K, Lee J, Boucher RC, Teichmann SA, Warner BM, Byrd KM, et. al Nat Med. 2021 Mar 25.​

 

Which explains why 2-year olds are a major vector?

Do I believe that saliva CAN contribute to the spread of this disease?

Yep.

Do I believe that it's a major factor?

Noooope.

Science and data......

 

I wouldn't conclude that so quickly. The point of the study was that the researchers found that both oral epithelial and salivary gland primary cells express the ACE2 receptor and TMPRSS2 enzyme necessary for the SARS-CoV-2 to enter the cell and demonstrated that the virus indeed infects those cells and replicate inside of those cells. The study also found infectious agents in the saliva of people with mild or asymptomatic COVID-19 can infect healthy cells. The results explain why when people speak, cough, and even sing, can spread the virus and why the mask worn by asymptomatic COVID-19 infected individual can be very effective in preventing the spread.

 

Concur.....but at what range? (Agree that I did not express myself earlier)
For How long?

Not saying masks are not effective, BUT:
Outdoors?
>6'?

The saliva spread theory has been used to suggest that schools should stay closed.....
States that do not do this suggest otherwise.
Planes with butts in middle seats and people stuffing peanuts into their pie-holes suggest otherwise.....
Restaurants.
Bars.
Churches.

There CAN BE no doubt that aerosolized spit spreads the bug.
I'm just a harder sell on surface contamination being a primary spreader, and I also believe (based on what we can know to date) that masks only stop the big stuff.

I'm not that much of a hard sell on masks.....but padlocking businesses, grounding planes, and closing schools?
Not so much.


Time
Distance
Shielding.

YMMV

 

Without quoting specific references, I would guess it is the same as any COVID-19 infectious agent deposited by the infected person whether it comes primarily from respiratory epithelial origin or oral epithelial orgin.

The paper does not comment on anything on the mode of transmission. There is no data or not even a suggestion in the paper that the infectious agents contained in the saliva are primarily transmitted via contaminated inanimate objects by surface to hand to nose or mouth. The way I interpreted the results of the study is that saliva from the oral cavity of the infected individual can be spread more easily by the aerosolized droplets in asymptomatic and mildly symptomatic individuals without having any respiratory symptoms.

Yes, the question still remains which mode of infections, oral or respiratory, comes first and is predominant for the pathogenesis of COVID-19. We will have to wait for future cohort studies to answer that question. Here is the excerpt from the paper pertaining to that future study.

However, these results raise new questions about COVID-19 pathogenesis, including 1) whether this is primarily a ‘nasal-first’ infection that spreads to the oral cavity, 2) the possibility of an ‘oral-first’ infection via droplet/aerosol inoculation or fomite ingestion, and/or 3) whether the pattern of infection affects disease severity and host immunological responses. To test whether oral transmission can precede nasal infection and/or occur in the absence of nasal infection, it will be necessary to design studies that include daily surveillance using NP and salivary tests in an at-risk cohort.​

 

Copy....

I'll give the study a more thorough read-through.
As always....."Novel = new"

 

but dr fauci said it was okay to get takeout

 

from what you printed, i take it that it can 'affect' the mouth, and spread needs further study

 

The study showed that the SARS-CoV-2 can infect cells of the mouth lining including the glandular cells that produce saliva. This was never shown before. It was well known and understood that the SARS-CoV-2 infects respiratory cells of nasal lining and airways of the lungs. The fact that the viable infectious materials were found in the saliva of non-symptomatic patients implies that it can be a source of infection that spread within the body of the patient as well as spread to other people. The site of the first infection can be at the nose or at the mouth, but it needs further study to show which is first and more prevalent.

Yeah, take-out is fine. Delivery is also OK, I guess. I still would not dine inside a restaurant or a bar. But even before the pandemic, we rarely dine out or go bar hopping, so that is no change for me.

 

that is confusing to me. how should it change our behavior?

 

If you are already following what CDC recommends, then I don't see any need for change in behavior whether the infectious agent comes from the nose or mouth. It most likely comes from both of them when viral load is high in an infected individual. And some people never wear a mask anyway.

 

thanks sal!

 

Not sure how much coverage you might have had on this on your side of the pond.

This last week, three of the top rated medical journals (BMJ, Lancet and JAMA) have published commentaries making the same point - that aerosols are the dominant mode of transmission. Not without controversy, but it appears that the scientific evidence from different researchers all seem to point in this direction - that infectious aerosols are the principal means of person-to-person transmission.

Their plea was to public health officials and bodies like WHO to take this up and run with it.

For me, in medical practice, it does make much sense and helps to explain many of the odd stories of transmissions we have heard and of the superspreader events, including that of the Diamond Princess (remember that, way back then?)

I'll post the link to the Lancet commentary below, but a brief summary can be found here:
10 Reasons Airborne Transmission of SARS-CoV-2 Appears Airtight

In case it is behind a paywall for some of you, the message is:
1. Less focus on large droplets and fomites (a.k.a., contaminated surfaces)
2. More focus on good ventilation, air filtration and less exposure to 'shared air'
[and when not possible, masks and social distancing to minimise exposure]

For me, the simplest take home message to remember was this concept of avoiding 'shared air'.

https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)00869-2/fulltext