francksteel: 1# That's so much different of what we live in France. As if it was 2 differents viruses. No recent TB vaccine may explain that (don't know the figures for the different countries of Europe to have a hint of the plausibility)
Although, even if I take the figures you gave (0.37%), that would mean that in France around 5 millions people have already been infected, and that we could have more than 200 000 deaths. Still far more than a flu (around 10 000 per year)
2# How long this immunity lasts ? Any clue about that ?
3# Seems contradictory to me with the rest of the post. Why are there so much spreading in countries where social distancing and stay at home measures have already been made for more than 3 weeks now ?
There is also the case of the Charles de Gaulle, French Aircraft carrier. No contact with land since 15th march but 50 positives cases recently on it.
Incubation could be far more than a few days but to be counted in weeks ?
1# I would not think that 5 million people in France are infected, its probably around 500.000 at worst. Only a wide range of NAb testing can give closure during the month of May.
2# Hard to tell, I'd say 2 years (people who survived SARS had immunity for about 5 years). We already know that SARS-CoV-2 is about 33 times "stronger" than the flu if we consider general mortality rates. India does seem to be an total outlier. From the virus perspective its living in a paradise there (highest population per km² within the larger cities) but the infection rate does seem much lower and thats most likely because of the prior vaccines.
We know whether or not TB vaccination helped within the next month I'd say.
3# Not contradictory, measurements are at place to decrease r(n) rate by about half (hypothetically from about 2.2 to 1.1 at best.) Considering how it spreads around communities you also have to consider that denying spread through communities through physical distancing/basic hygene management measures means denying the virus access through person-to-person droplet spread on a local scale. Remember that this study is conducted on people who got infected before these general measures took place, so most people there as of today are already are already recovered and have antibodies or are at least very close to it.
Numbers of infected people are already going down all the time in France,
just look at this for clarification and general projections as they seem mostly very accurate and based on statistically verifyable data.
Regarding the Charles de Gaulle case. First you have to consider that people inside an aircraft carrier live close together within a confined space. Even if there was one infected person throughout late feburary, entering such confined space could still result in spreading the virus, it will result in more people getting infected. And besides, was everyone working inside the Aircraft Carrier tested systematically? The next post consideres that this is not the case, so if the facts are different from what I'm speculating you can disregard most of it.
Here is how people spread the virus.
Virus enters your body, then incubation time within 2 days up to 16 days. 1.5 days before symptoms are signified, the virus can spread to other people. You lose your sense of taste and smell for a short while, then 4-7 days later this sense comes back. After that the second phase of the illness begins where the virus enters the lungs and the antibodies combat it (which can be compared to a very bad flu or a much less severe form of SARS-CoV). During that second phase, the virus will not exert out of your body, you cannot infect others during that phase.
So if one person got infected during the lets say 14th of march and then enters the confined space, chances are that it may take weeks for people to notice (up to early april). And after that period it may take a couple of weeks to notice that others might be infected as well. I can accurately say that at least 150 people on the aircraft carrier are infected (they don't notice this), considering the virus has a R(n) of about 2.2. The number is most likely higher, considering a lot of times this illness is not really noticed and only PCR and "next gen" NAb tests can give closure to that number.
Besides, from the antibodies standpoint, even if the human dies, the virus will always lose the fight. What matters here is the incubation period and the first phase, where the virus is highly infectious and must spread (which is why quarantaining is so important). And again, you can infect people 1.5 days before the illness begins, kinda like with the regular flu. At any case, this virus is fighting a losing battle.
Not only that, there are already types of medication that can completly halt the virus during the first phase (Avigan seems to be a safe bet, though there are side effects). What is only really dangerous is the second phase of the illness. If people can treat the first phase of the illness you can completely stop the virus from getting into the lungs. Pretty sure that with cases like special confined space ones people should threat these infected people with such medication before phase 2 of the illness begins.
To visualise infection spread as an abstract,
look at the game of life for visualisation. White boxes = general populous while Black boxes = infected populous.
EDIT: Forgot a few things but not anymore :>! And sorry for writing so many "considerings", most of the stuff is not yet wholly objectively proven, though there are some objective qualities already. People are figuring out more and more regarding this illness. Not only that but I assume that mass vaccinations may already become available shortly before september this year if the pace of gathering knowledge and general testing (also general projects regarding experimental antibody testing in general) is any indication. This never happened before with such speed. This actually is 20 times or quicker than how usual medical research operates. Pretty sure that if things keep up, we may even find a cure regarding lung fibrosis within the next few years as there already is a cure for this but for mice and it still need human testing.