How long will the Covid-19 pandemic last? We need immunity data to find out. – Vox:

‘If immunity lasts a couple of years or more, Covid-19 could fade in a few years’ time. If immunity wanes within a year, Covid-19 could make fierce annual comebacks until an effective vaccine is widely available. While there’s hope that a vaccine will become available, it’s not a given. The vaccine could also be less than perfectly effective. Manufacturers could struggle to produce enough of it.

Immunity is one key to understanding the duration of this pandemic. Here’s what we know about it so far, and how scientists can crack the mystery for good….’

— Via Vox