SARS-CoV-2 Coronavirus (COVID-19)

WHO sitreps here:


Situation reports


Newest #24 describes category change. Briefly, confirmed now includes folks with particular features on lung xray and particular travel history. Not only positive DNA tests.

If readers find another source providing additional detail on this shift, please post.

I must say that redefinitions do not explain large daily fatality increase.
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Concerning thread title, adding COVID-19 is perfectly appropriate. We all participate at the pleasure of PriusChat moderators.

 

From WHO sitrep 24

"Overnight 14,840 cases, including 13,332 clinically diagnosed cases were reported from Hubei. This is the first time China has reported clinically diagnosed cases in addition to laboratory-confirmed cases. For consistency, we report here only the number of laboratory-confirmed cases. WHO has formally requested additional information on the clinically diagnosed cases, in particular when these have occurred in the course of the outbreak and whether suspect cases were reclassified as clinically diagnosed cases."

I added the emphasis. Other sources defined "clinically diagnosed" as xray plus travel history. Other sources defined "laboratory-confirmed" as presence of genetic sequence(s) peculiar to this virus. I could track down what those were, but I have no doubt in accuracy of either definition.

Please note that this refers to definitions of these categories. I know of no other site than
https://ncov.dxy.cn
that is updating "clinically diagnosed" in China. My concern there is that updates are irregular through time (more than once per day) and I do not have a strict schedule for obtaining numbers on that page.

Please also note that I have no way to independently verify any numbers in sitreps or ncov. I use them to inform models not all of which I have yet presented here.

 

A deeper dive into infectivity:

WHO underestimates the spread of the Coronavirus -- ScienceDaily

 

Vaccine @236. This candidate is a DNA vaccine and I will say some things about that. If there are errors, I or someone else could help with cleanup,

Corona viruses have RNA. This one was sequenced in early January and made public. It is (nowadays) trivial to made its DNA version. ACGU -> TGCA, with much complexity and detail omitted. Some chunk of that DNA is selected for future use.

The short unique DNA sequence is not a vaccine. It is first vectored into some friendly bacteria's plasmid with some friendly virus. This is now standard toolbox (believe it or not, and it very much was not when I studied these things in school). That transformed bacteria is the vaccine.

Vaccine enters Bob Wilson's arm (he said he'd volunteer). Now a benign bacterial infection grows in Petri-Bob. That bacteria has in addition to its normal 'load', an otherwise useless DNA sequence that was added as above.

Next part is not quite clear to me, but that DNA is transcribed into RNA which to some extent leaks out of bacteria. Various immune cells in Bob (B-cells and T-cells it seems) create antibodies against that RNA sequence.

Later, if Bob forgets to wear his facemask or wash his hands, maybe this corona virus arrives. Bob's new antibodies against that RNA sequence enter the fight, and super-Bob does not become a statistic.

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One can appreciate that several steps lie between existence of that altered bacteria, to immunological protection, without unintended side effects. I suppose mice and some other primate will be Petri dishes before any such vaccine has human trials. Company mentioned @236 and several others will carry out those steps (at some expense) before they have a product to sell.

At least one of the SARS corona virus vaccine candidates worked like that. Completion of their testing was ended when SARS stopped transmitting between humans in the wild.