The world is going on lockdown in many areas because of the mathematical projections of what can happen without Non Pharmaceutical Interventions, NPIs, we all are doing. Because the worlds population is 7,770,631,490 and as a pandemic without a vaccine yet, no immunity,
and no treatments at this time (which may never come to low healthcare countries when folks have ARDS etc...During the Spanish flu, for instance, the death rate ranged from less than 1 percent in some areas to 90 percent in one Alaskan village.)... We posted many of those projections on the first 2 threads.
It is worrisome indeed, and the reason for the lockdowns, NPI's and global education and alarm.
Put the numbers together with a disease that has an R0 of ~4% (
without social distancing and other NPI's that China and other folks are doing with isolation/shutdowns) would require 75% of the population to become infected to reach herd immunity. So, eventually that would mean those 20% infected would need hospitalization eventually. Scientists don't think we may get to that and we won't reach those numbers when a vaccine is created, yet until then...it will potentially grow in exponential waves that we try to push back with NPIs.
Here is a good read...
Covid-19 Is Nothing Like the Spanish Flu
Also, read up on herd immunity vs. R0 at
What is Herd Immunity?
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In above, in leiu of vacine immunity - assume immunity due to already had the disease. GAWD forbid if this virus doesn't give lasting immunity with IGg and IGm antibodies!