What a 95% Effective Vaccine Could Do Is Pretty Exciting
A percentage point here, a percentage point there and pretty soon you’re talking about real progress in the battle against Covid-19.
Pretty amazing.
Photographer: JOEL SAGET/AFP/Getty Images
In wealthy Western countries with lots of older people, the coronavirus that causes Covid-19 has killed roughly 1% of those infected with it, meaning 99% survive. Meanwhile, two new vaccines have so far been found to be about 95% effective in preventing symptoms of the disease.
Lots of people seem to have trouble thinking through percentages like these. While I hesitate to elevate the since-deleted thoughts of a pseudonymous dude on Twitter as representative of anything in particular, the quote that follows is such a succinct expression of that trouble (plus it had gotten more than 12,000 retweets and 45,000 likes before being deleted) that it seemed worth sharing and then working through:
Where to start? Well, first, a virus that is “99% ineffective in killing anyone” can be quite deadly.