I haven't changed anything in my investments. Then again, I keep a decent cash emergency fund. I originally was going to dump my tax return into my investment account, but I'm hesitant to do this because I haven't yet rebuilt my emergency fund to what I prefer (I used part of it to max out my Roth on January 1). Granted, I could still go 8 or 9 months without a job, though without going into too much detail, my current job is likely to earn new clients in the event of a pandemic.
Oooh, that's tough. I could probably dump half of my tax return into VTSAX, given the discount and all. As long as I make it to next paycheck (highly likely), maybe I can dump the whole thing. You can't call the bottom, but you can get a great discount. I really wouldn't mind the recession starting when I'm so early in building my stache, just as long as I and my family can stay employed.
I'm more worried for my parents and grandma. This virus is scary stuff, even if it isn't the end of the world. We've had it pretty soft here in the US, though. And history knows far worse.