Will it ever end? In November, we were celebrating the announcement that the BioNTech/Pfizer vaccine seemed to be highly effective against Covid-19, followed with bewildering speed by similar claims for the Sputnik V, Moderna and Oxford/AstraZeneca vaccines. Nearly three months later, hospitals are overwhelmed and the global death toll is climbing twice as fast as in the worst days of the first wave.
At a time like this, I reach for my calculator. Without minimising the suffering so many people are enduring, I think there is potential for rapid progress very soon.
There are two reasons why these vaccines, some highly effective, have not yet done anything obvious to save lives or protect hospitals.
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