To mask or not to mask? But why? Does anyone know?

Tomorrow evening Stew and I will be going on a thrice-postponed trip abroad, our first since the Covid-19  pandemic began more than two years ago. We've been vaccinated twice and received the booster, in addition to a flu vaccine and the first of two shingles vaccines. And of course, we'll carry our KN-95 masks in …

Continue reading To mask or not to mask? But why? Does anyone know?