Measles as a best-case study of how humans stack up to respiratory viruses?
Nearly two years ago, when public health officials first began talking about “science” in the context of the measures they were taking that would eradicate SARS-CoV-2, the medical school professors whom I know would point out that humans had never beaten a respiratory virus and therefore there was no possible scientific basis for a confident belief that a proposed intervention would be effective.
Influenza is a familiar example of respiratory virus that has laughed at our science and medicine. The common cold viruses are another class that are apparently smarter than us. Measles is a unique case. It has a bizarre-for-an-organism inability to mutate. “Why you need one vaccine for measles and many for the flu” (ScienceDaily, 2015):
The surface proteins that the measles virus uses to enter cells are ineffective if they suffer any mutation, meaning that any changes to the virus come at a major cost.
It’s only possible to speculate why the measles virus would find an evolutionary advantage to being so rigid, but one hypothesis is that measles uses a more complex strategy to get into human cells than influenza. Influenza, for instance, simply requires the binding of one of the sugars that decorate the outside of cells as a means of getting inside. In contrast, measles requires binding to specific cellular protein receptors as its doorway.
Since measles can’t mutate, we have great drugs for treating it and near-100 percent vaccine coverage all over the world, right? Wrong. In fact, measles kills roughly 200,000 people per year (WHO). They’re mostly under the age of 5 so they would have lived at least 50 more years, even in the poorest countries. That’s 10 million life-years lost every year to measles.
How does losing 10 million life-years compared to the killing done by COVID-19? WHO says that 1.8 million humans were killed by COVID-19 in 2020. Unless each one had another 5.6 years to live, which seems unlikely given that the typical victim in Massachusetts was 82 with comorbidities, measles actually took away more life-years than COVID-19. And if we use the British technocrats’ quality-adjusted life year, measles was far more destructive than COVID-19. Measles prevents people from enjoying their healthiest and most vigorous years while COVID-19 chops off the years during which electric scooters are required for mobility.
(The above paragraph raises the obvious question of why hardly anyone in the EU or US cared about measles deaths prior to 2020 or, even now. Nobody would have been willing to spent $10 trillion to save 10 million high quality life-years destroyed by measles.)
Because it is free to mutate, SARS-CoV-2 is a much more elusive enemy than Measles morbillivirus, yet I think our definition of success against COVID-19 is much more stringent than the standard we’ve applied to ourselves when fighting measles. Unless humans have become vastly more capable in just the past year or two, aren’t we setting ourselves up for disappointment?
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