No, Reiki is a practice of giving energy, not taking it. The only way you could get an illness from someone you’re giving treatment from is if they were contagious (cold, flu, etc)… same thing doctors, chiropractors, massage therapists, etc have to worry about when they are giving treatment. If you’re near someone who’s sick, you risk getting sick. Aside from that, no, you can’t take on their illnesses because you aren’t taking their energy on yourself. Good luck and I hope I helped!
no. I mean, you could get a cold or whatever from coughs and sneezes type stuff but never from Reiki.
You are channelling the energy through you, to the person. If you are particularly sensitive then you may sense how they are feeling etc but if you have grounded yourself well and have brought down protection etc as you should be doing then you will be fine.
If you don’t know how to bring protection, here is a simple way. Close your eyes and imagine a white ball of light around you, see it getting stronger and stronger and not letting anything past.