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:
Forgive me if I’m not excited about a vaccine that is 95% effective against a virus that is 99% ineffective in killing anyone.