https://danbooru.donmai.us/posts?utf8=%E2%9C%93&tags=uzaki-chan_wa_asobitai%21+take_%28shokumu-taiman%29+&ms=1 This page has a lot of the original twitter pics translated to english with annotations. The Snipperclips one is pretty good.
@aFFI It has been proven that being cold (and cold weather) weakens your body's immune response. It won't suddenly make a virus appear in your body, but will make you more vulnerable to anything you're exposed to.
@Boboloboloo
Yeah, I know. Well, to be exact, "lower temperatures weaken the nose’s first line of immune defenses." source
The thing is, you still have to be in contact with a virus carrier. And the temperature needs to be pretty low, to get your body temperature like 3-4°C lower than normal.
By running in a summer rain without meeting anybody on the road, your chances of getting the flu is pretty close to none. Otherwise, getting to the pool in summer would create a flu pandemic...
I might be remembering the fight wrong, but doesn't Sundowner only combine his blades into shears after you lop off all of his shields? If I'm not incorrect, this renders the chapter unreadable.