More solid than a humorous JPEG without doubt but not of the observation of the facts.
The Chinese Nature study dates from April 15, 2020, since we have made a little progress on the subject, particularly in Wuhan (place of the study).
The principle of the study is based on the assumption:
"If the observed mean serial interval is shorter than the observed mean incubation period, this indicates that a significant part of transmission may have taken place before infected people developed symptoms."I believe the Jamanetwork study is based on the same assumption, in addition they consider that: "30% of infected people never develop symptoms and are 75% as infectious as those who develop symptoms."
It is from this assumption that they obtain their 50% average.
It appears that Michael A. Johansson, author of the Jama study, is an expert in mathematical modeling. Here, a 2008 study on the risks of alarmist spread of yellow fever in the absence of a vaccine:
https://www.ajtmh.org/content/journals/ ... l_fulltextThere is no doubt that this kind of study will receive numerous financial sponsors ...
For the Chinese, still in Wuhan, I have already cited a recent study and
not mathematical but observational which indicates the non-transmissibility of asymptomatic:
https://www.nature.com/articles/s41467- ... t=deeplink“All city residents aged six years or older were eligible and 9 (899%) participated. No new symptomatic cases and 828 asymptomatic cases (detection rate 92,9 / 300, 0,303% CI 10-000 / 95) have been identified.
There were no positive tests among 1 close contacts of asymptomatic cases."
Of the 10m of inhabitants tested, it was detected that 300 asymptomatic and none of their 1174 contacts were infected. ZERO.
The other study is done in singapore and
also observational : You will note in passing that it's funny but in Europe and the US we only do mathematical modeling studies and no observational studies. But it's true, if it's not "evidence based" "randomized" "against control group" etc etc, it is a hell of a lot worse.
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)32651-9/fulltext#back-bib4"Negative binomial regression revealed that, adjusted for age, sex, and serology of the index case, the incidence of COVID-19 among close contacts of a symptomatic index case was 3,85 times higher. higher than for close contacts of an asymptomatic index case (95% CI2 · 06–7 · 19; p <0 · 0001). "Personally, I assume that asymptomatics are at worst 4 times less contagious at best not contagious at all. Which actually messes up absolutely all the global liberticidal measures.
In other words, any study that shows that asymptomatics are little or not contagious goes against the decisions of most Western governments. All those who say the opposite are relayed and amplified by the media.