Sweden says officially it’s approaching that level of immunity. Others say that a death toll of 2000 dead, admittedly including those in high-risk groups, doesn’t prove anything of the sort. COVID-19 is a new disease. Immunity is a long way from being proven. It’s not the mumps or the measles. It’s a member of a known dangerous class of viruses.
All seems pretty sedate so far, doesn’t it? A nice safe argument to keep the mental mold from overexerting itself. There’s another side to epidemiology and it’s much less fun.
Consider the Ebola outbreak in West Africa in 2014-16. This presumably adorable virus killed 10% of the current global death toll in just 3 countries. It’s ultra-contagious. People bleed in front of your eyes. It created a very understandable panic. Imagine our global COVID-19 toilet paper hoarding heroes in a scenario like that.
This virus doesn’t give immunity as such. Survivors, for example, may be immune to the Ebola they had, but not to other strains of it. That’s a general rule with viruses. All strains have differences. Herd immunity, therefore, isn’t a free pass out of trouble.
So you can have a lot of people who think they’re immune to a virus who in all practical terms are nothing of the sort. For the same reason there are annual flu shots, the viruses change. Last year’s inoculation doesn’t make you immune to the next wave. COVID-19 so far has been an ongoing proof of the built-in uncertainties in pandemic diseases.
The problem is this:
If you create a single-track broad-spectrum strategy, it can’t possibly fit the individual circumstances of a given virus. There are too many possible variables, including the virulence of any given disease. Immunity may or may not happen in a best case scenario, and usually doesn’t happen at all.
In fairness, the Swedes aren’t claiming to have any proof of actual immunity. It’s the principle they acted upon. That principle has one working part that’s verifiable – Diseases never wipe out entire populations of their hosts.
They can, however, and have, wiped out 30% of Europe’s population in the past, in successive waves of the Plague. The Athenian Plague during the Peloponnesian War effectively shattered the city. The Antonine Plague decimated Rome.
There is no reason to believe that the gigantic numbers of people on Earth now can just naturally become immune to diseases that mutate so often. Statistically, something a bit more infectious and dangerous than COVID-19 could trash the planet very effectively.
Herd immunity isn’t just a bad idea. It can’t work with viruses. It could well be a disaster if you assume any kind of immunity is conferred by having a virus. You might also try using an expression a bit less obviously indicative of contempt for human life and loss. It’d be a nice change.
