- Position‹3 of 4›
- Herd immunity is a risky bet
- Argument‹2 of 2
Herd immunity is risky because the virus could mutate
Just like any other virus, the coronavirus could mutate and become deadlier than it already is.
The argument
Herd immunity works on a simple assumption: that once a large enough share of a population has been infected and recovered, the immunity those survivors carry will deny the virus the hosts it needs to keep spreading. That assumption holds only if the immunity acquired against the virus remains immunity against the virus people will actually encounter later. Viruses do not stay still. As a host's body mounts a defence, the virus is placed under pressure to adapt to a changed environment, and the variants that happen to survive that pressure are the ones that get passed on. Those adaptations can include changes to the surface proteins by which the immune system recognises the virus in the first place. This is what makes the strategy a gamble rather than a plan. If the coronavirus mutated enough to withstand the body's existing defences, the immunity accumulated through mass infection would no longer correspond to the thing it was supposed to protect against, and a population that had paid the full price of reaching the herd immunity threshold would find itself unprotected anyway. The protection would have been bought against a virus that no longer exists in that form. Mutation also carries a second risk, which is that the altered virus is not merely different but worse. New variants can bring new and sometimes more severe symptoms, so a population pursuing herd immunity is not only risking that its immunity expires but risking that what it eventually faces is more dangerous than what it deliberately allowed to spread. Deliberately letting a mutating pathogen circulate through a population is therefore a bet on the virus staying recognisable, and that is not something the strategy can guarantee.
Premises
Counter-arguments
The chances of the coronavirus mutating are slim. For a virus to evolve, there would need to be several mutations that give the virus an overall environmental advantage. Therefore, there is no need to worry about the effectiveness of herd immunity.
Rejecting the premises
[Rejecting P1] Viruses rarely have enough mutations to evolve.