WHO changed its definition of herd immunity (see below), just like they changed the definition of 'pandemic' back in 2009 to induce public fear and sell H1N1 vaccines for a 'healthy' profit for a non-existent pandemic (original definition
here and new definition
here).
Don't forget WHO is a private company funded by pharmaceutical companies, or those with vested interests, (just like the CDC) that has patents for various things like vaccines and drugs, and is currently headed by a non-medical bureaucrat (that has been implicated in horrific war-crimes in Ethiopia).
We are currently being dictated to by unelected and unaccountable technocrats who change the rules at will without any legislative/societal input.
They have effectively mandated all of our Constitutional and Human Rights are of no value to be enforced with the full physical force of our police.
As soon as they declare an 'Emergency' you and I relinquish the vast majority of our freedoms and paths of redress for governmental tyranny,
and they will seek to expand the powers and duration (if you doubt this look into
Bill C-19 in BC).
CDC June 9, 2020 - Herd immunity is the indirect protection from an infectious disease that happens when a population is immune either through vaccination or immunity developed through previous infection. This means that even people who haven’t been infected, or in whom an infection hasn’t triggered an immune response, they are protected because people around them who are immune can act as buffers between them and an infected person. The threshold for establishing herd immunity for COVID-19 is not yet clear.
Link
CDC Oct 15, 2020 - ‘Herd immunity’, also known as ‘population immunity’, is a concept used for vaccination, in which a population can be protected from a certain virus if a threshold of vaccination is reached.
Link