Herding [verb]

A mutated virus could become an entirely new disease that sidesteps the vaccines now under development and whatever progress we have made toward herd immunity.

This year’s pandemic is only the latest thinning of the herd.

That’s led to higher infection and mortality rates than in the rest of the Nordic region, but so far with few signs that Sweden has developed herd immunity.

Establishing herds of cattle with disease-acquired immunity was an acceptable practice in the early 20th century because brucellosis was not deadly to livestock and there were initially no effective treatments or vaccines.

As Cormac McCarthy might say, if that ain’t herd immunity, it’ll do until the herd immunity gets here.

Others claimed that herd immunity would kick in once enough people had been infected.

Without knowing how long immunity lasts after an infection, and how much that varies from person to person, it’s impossible to know whether ending the pandemic through herd immunity is even possible.

The trouble is that herd immunity is a process that takes time and caution.

Never in the history of public health has herd immunity been used as a strategy for responding to an outbreak, let alone a pandemic.

This was the only way that high enough levels of protection could be achieved across the world to reach the threshold for herd immunity.