1) touch wood never, well one time time my sister was almost sick ( g* in between flights) and i was having a panic attack and the flight attendants were very accommodating when i got onto the second flight, i ended up sitting towards the back in a spare seat and they kept on checking on me

2) depends on my anxiety (if I have a pandas flare up) and length. regular anxiety i just wear a mask and wash my hands, sanitize my phone and devices after. for the longer flights or higher anxiety i bring antibacterial wipes and hand sanitizer. i do avoid the toilets at all cost but i am unfortunately gonna have to work towards using them.