Poor baby!! I also think you should try to get him trapped. I can totally understand that you don't want to bring him into your house, to the other cats. It's very likely that he is positive, from the way he looks.

Poor kitty! When will people finally get rid of this romantic illusion that this world is a paradise for ferals! Reality is somewhat different, and this poor guy is just one of many!

I'm sorry that this happened to you, but you are a person who cares!

Kirsten