If we assume the IFR of COVID-19 is 1% and herd immunity is reached when 70% of the population is infected, the epidemic will fade when 2,297,400 Americans have died of COVID-19.
“The coronavirus moved so rapidly across the globe partly because no one had prior immunity to it. Failure to check its spread will result in a catastrophic loss of lives. Yet some politicians, epidemiologists and commentators are advising that the most practical course of action is to manage infections while allowing so-called herd immunity to build.
The concept of herd immunity is typically described in the context of a vaccine. When enough people are vaccinated, a pathogen cannot spread easily through the population. If you are infected with measles but everyone you interact with has been vaccinated, transmission will be stopped in its tracks.
Vaccination levels must stay above a threshold that depends upon the transmissibility of the pathogen. We don’t yet know exactly how transmissible the coronavirus is, but say each person infects an average of three others. That would mean nearly two-thirds of the population would need to be immune to confer herd immunity. …
Perhaps most important to understand, the virus doesn’t magically disappear when the herd immunity threshold is reached. That’s not when things stop — it’s only when they start to slow down.”
As Carl Bergstrom explains above though, it won’t stop there. It will just slow down and we will end up somewhere past the original Imperial College estimate because of overshoot.
Congratulations to our political class for your decision to “ride it out” and “think of it as just the flu” in order to avoid “spooking the markets” in February. You are as stupid, evil and incompetent as I have always said you were since 9/11, the Iraq War and the Crash of 2008.
If this forecast is accurate and 2.2 million Americans gradually die from COVID-19 over the next two years until herd immunity achieved, it will be the most devastating loss of life that has ever happened in American history. It will be worse than the Civil War, the Spanish Flu, Iraq and Afghanistan and all the wars of the 20th century combined. It will be an unfathomable national tragedy.