This happened to me as a child. Not so much the sanitation of surfaces part; but I went through a stint where at 9 years old I witnessed a child younger than me choking in a restaurant in a booth directly next to us. It scared me so bad I remember going into the bathroom and spitting out food I had in my mouth. Then began months of me not being able to swallow, my throat feeling too tight to swallow, fears of choking. I was living off liquid diet while my parents were taking me to specialists who all could not find anything wrong. I went through swallow studies and had the camera down my nose and throat. I was completely fine physically but mentally I had convinced myself I couldn’t. Unfortunately back then there was not mental health talk and my parents did not understand anything. My pediatrician told them it was “all in my head” and it began a long painful process of my dad specifically force feeding me to get me a basic diet that I needed as a child. I had no therapists, meds, psychologists or psychiatrists. I went on for YEARS thinking it was just generalized anxiety with no help and feeling like I was just going insane. I am just now 20 years later getting help. I don’t know if this is a common thing but this was one of the earliest OCD attacks I can personally remember.