50% vaccinated?
How in the heck does that statistic translate into "herd immunity"?
Is there any medical proof, for this virus, that any such measure results in "herd immunity?
There is no way I’m taking the “Bill Gates vaccine” - far more dangerous than the flu that has a 99.5% survivor rate.
Additionally, I haven’t had a cold or flu in years and years...and I’m a “seasoned citizen”.
The Herd Immunity Threshold (HIT) is the point at which enough individuals within a population are immune to a disease (either because of infection or vaccination) that each infection produces less than one transmission (new infection) on average (Rt). With an Rt of 1, each infected person spreads the disease to one other person on average, so the disease can continue to propagate. At an Rt value less than 1, cases dwindle toward zero.
We calculate the Herd Immunity Threshold using the R0, which is the number of new infections spawned - on average - from each infection in a population where nobody has any immunity through prior exposure or vaccination. The formula for HIT is 1-1/R0. The R0 for the original SARS-CoV-2 variant (from November 2019 - around February 2020) was around 1.8. 1-1/1.8 gives us 0.44 or 44%. In April 2020, a new variant that spread far more rapidly completely replaced the original variant in a matter of weeks across the globe. Its R0 is roughly 2.5, giving us a HIT of 60%. In Fall 2020, new variants in the UK and South Africa emerged. The R0 is still being narrowed down, but it's believed to be roughly 4.3-5.7, giving us a HIT of 77-82%. For reference, Measles has an R0 of 12-18 and seasonal flu has an R0 of 0.9-2.1.
"Is there any medical proof, for this virus, that any such measure results in "herd immunity?
There's nothing special about this virus, so basic rules of epidemiology apply. It spreads at a certain rate. If enough people are inoculated (through infection or vaccination), the virus can't find vulnerable hosts and it dies off.
At the current rate of infection and vaccination, the US will reach HIT by about July of this year. After that point, we'll see cases slowly decline toward zero. By the end of this year, the media will be reporting on individual cases of COVID-19 discovered because they'll be so few and far between.
RE: What does “herd immunity” mean? 50% vaccinated?
It says in the article:
Scientists have not reached a precise consensus on how many members of a population must be immune to the virus to have reached herd immunity, but common answers range from 60%-90%.
The number of new cases has been dropping like a rock. Perhaps you have a scientific theory about that.