While it certainly can be lethal, it is certainly no where near the same as the .223.
Man shot in head 5 years ago didn’t know it
http://www.cbc.ca/news/world/story/2010/08/24/germany-shot-in-head.html
A Polish man living in Germany was shot in the back of his head five years ago but didn’t realize it until just recently, police in Bochum said Tuesday.
The 35-year-old man was drunk and partying in the western town of Herne when he was hit by a .22-calibre bullet, police said.
You really have to be up close and personal. Then too, what size .22 was he hit with and how far away was the shooter? Most “assassination” guns are .22’s - the Israeli Mossad uses them. A .22 will whiz around your brain box scrambling it.
Maybe it was a .22 airgun pellet.....