A thread on why COVID (aka SARS-2) is a lot better at spreading than the original SARS virus.

1) it infects tissues in our throat where it can replicate undetected for days before causing symptoms https://twitter.com/PeterKolchinsky/status/1246975285792329730

2) which is why masks, which are really good at keeping our OWN cough droplets from spreading, is so helpful. Wearing them anytime we go outside, even if we don't feel sick, is a great way to keep from spreading COVID from asymptomatic infections.