Zacki Profile picture
armchair virologist hobbyvirologe answers with 'look at pop density' or '60-70%' get muted. the real gesundheitsexperte.
9 Sep
No-Lockdown Uruguay is the blue spot on the red continent below. Positivity Rate is 0,7%; neighboring countries surpass 50%. Plausible?

Uruguay´s success story: They invented their own PCR test. With their own primers, and a Ct value <35. For comparison, CDCs PCR uses Ct <40. Image
We should not compare countries without knowing the "market share" of the test they use. And we have to compare the tests (test-test-reliabilty).

Here is a paper about uruguay´s special response:
medrxiv.org/content/10.110…
Sensitivity and Specifity of the different PCR test are not only defined by different Ct values, but also different primers and gene loci make a big difference.
Read 4 tweets
8 Sep
Innate immunity - the strong and fast first layer of our immune response.

Only minutes after entering our body, most -up to 90%- of pathoges are cleared by this "archaic" system.

Endeless-🧵⬇️
(to be updated from time to time) Image
Innate immunity destroys structures that are alien to the human organism.

It´s always there, in contrast to B-Cells (Antibodies) and T-Cells it is *not* adaptive.

It does not depend on learning, but on finding structures that are typical of intruders.

🧵↕️
Covid19 is a ssRNA Virus with an envelope and a Spike Gylcoprotein, so it has some parts that are very different from human cells.

It should be a rather easy target for innate immunity.

Let´s have a look on some players of this arachaic system in this thread

🧵↕️ Image
Read 4 tweets
29 Aug
PCR is prone to contamination by very small amount of viral particles.

Hypothesis: we usually don't notice contamination, especially when it is happening *before* putting the probes into the PCR apparatus. This may even mimick a super spreader event.

Thread with examples
⬇️
France:

Contamination of a reagent. Not discovered by the laboratory, but by the local health authority which was skeptical about the sudden increase in cases.

amp.ouest-france.fr/grand-est/meur…
Read 24 tweets
11 Jul
#Sweden - #Mortality deaths per months 1980-2020

"I think it's like a severe flu season"
Professor Johan Giesecke

(update, putting all charts into one single pinned thread )
#France - deaths per months 1980-2020

In January 2017 more people died than in April 2020. But we saw no TGVs with ICU patients, and had no #crisesainitaire.
#Germany - deaths per months 1990-2020

In 2017/18, Germany was faced with the deadliest flu season of the last 30 years. Nobody took notice. We missed it. @Markus_Soeder did not protect us. And we had plenty of toilet paper.
Read 9 tweets
9 May
How much % is needed for #HerdImmunity? Not 60-70%, probably 10-20%. It depends on the variance in susceptibility - not everybody has the same risk to get infected. COVID takes the low-hangig fruits first.

medrxiv.org/content/10.110…
Read 5 tweets
4 May
Seasonality of #COVID is underappreciated.  Most human viral disease occur in distinct cycles. This is especially true for respiratory infections. We don´t know the reason for this, but it´s NOT simply “the weather”.

Regular seasonal variance is the rule, not the exception!
pubmed.ncbi.nlm.nih.gov/11384511/

This great paper from 2001 discussrs different theories about this topic.
Read 7 tweets